Quality Control in Fruit and Vegetable Processing

7/28/2019 Quality Control in Fruit and Vegetable Processing

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Q u a l i t y c o n t r o li n f ru i ta n d v e g e t a b l ep r o c e s s i n g


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Quality controlin fruitand vegetableprocessing

FA OFOOD ANDNUTRITION

PAPER

39

byP.W. Board

FOODAND

AGRICULTUREORGANIZATION

OF THEUNITED NATIONS

Rome, 1988


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Th e d e s i g n a t i o n s e m p l o y e d a n d t h e p r e s e n t a t i o n o fmate r ia l in th is pub l ica t ion do no t imp ly the express ion o fgny op in ion wha tsoever on the pa r t o f the Food andA g r i c u l t u r e O r g a n i z a t i o n o f t h e U n i t e d N a t i o n sconcern ing the lega l s ta tus o f any coun t ry , te r r i to ry , c i t yo r a rea o r o f it s au thor i t ies , o r co nce rn i ng the de l im i ta t iono f it s f ron t ie rs o r bou nda r ies .

M - 8 1I S B N 9 2 - 5 - 1 0 2 4 2 1 - 9

Al l r igh ts reserved . No par t o f th is pub l ica t ion may be rep roduced , s to red in a re t r ieva l sys tem, o rt r a n s m i t t e d i n a n y fo r m o r b y a n y m e a n s , e l e c tr o n i c , m e c h a n i c a l , p h o t o c o p y i n g o r o th e r w i s e , w i t h o u tt h e p r i o r p e r m i s s i o n o f t h e c o p y r i g h t o w n e r . A p p l i c a t i o n s f o r s u c h p e r m i s s i o n , w i t h a s t a t e m e n to f t h e p u r p o s e a n d e x t e n t o f t h e r e p r o d u c t i o n , s h o u l d b e a d d r e s s e d t o t h e D i r e c t o r , P u b l i c a t i o n sD i v i s i on , Fo o d a n d A g r i c u l t u r e O r g a n i z a t i o n o f t h e U n i t e d N a t i o n s , V i a d e l le Te r m e d i C a r a c a l l a .00100 Rome, I ta ly .

FAO 1988


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C O N T E N T SPage No.

CHAPTER 1 I NTRODUCTI ON 1CHAPTER 2 ESTABL I SHI NG QUAL I TY CONTROL SYST EMS 22. 1 P r o duc t i o n pl a nni ng 22. 2 I nt er ac t i on of qual i t y c ont r o l and pr oduc t i on s t a f f 2dur i ng pl a nni ng2. 3 Al l o cat i on of r e s our c e s t o qual i t y c ont r ol 32 . 4 Moni t o r i n g of t he manu f ac t u r i n g p r oces s 42 . 5 Moni t o r i n g o f t he manu f ac t u r i n g env i r onment 42. 6 End- pr o duc t t es t i ng 52. 7 I nc i de nc e of de f e c t i v e pr o duc t 52. 8 T r e a t me nt of qua l i t y c o nt r o l da t a 62. 9 S t a f f / management r e l a t i ons 6CHAPTER 3 QUAL I TY CONTROL SYST EMS FOR FRUI T AND VEGETABL E 10PROCESSI NG3. 1 Raw mat e r i a l s : 10- F r ui t s and v eg et a bl e s 10- Sugar , s al t , s pi c es , f ood a ci ds and ot he r m no r 11i ngr edi ent s- Wat er and s t eam 12- Co nt a i ne r s , l a be l s and pa c ka gi ng ma t e r i a l s 13- Det er gent s , s ani t i z er s and s i m l ar ma t e r i al s 143 . 2 P r epa r a t i v e t r eat ment s 143. 3 F i l l i ng 153. 4 Cl o s i ng and s e al i ng o pe r a t i o ns 153. 5 P r e s e r v a t i o n t r e at me nt s : 16- Canned f oods 16- Dehydr at ed f oods 17- F r oz en f oods 17- P i c k l e d and c he m c a l l y pr e s er v ed f o ods 173. 6 L abe l l i n g, p ackagi n g and war ehous i n g 183. 7 Cl e ani ng, s a ni t a t i o n and wa s t e d i s p os a l 19CHAPTER 4 METHODS OF ANALY SI S AND PHYSI CAL TEST I NG 204. 1 Scope 204. 2 Che m c al a na l y s es : 20- Ac i di t y 20- Af l a t o x i ns - r api d s c r e eni ng me t h od 21- Al c oho l i ns ol ubl e s ol i ds 22- Benz o i c aci d 22- Ca us t i c s oda ( l y e) 23- Chl o r i ne i n wa t e r 24- Mo i s t ur e 24- P er oxi das e 25- pH 25- Sal t 27- Sol ubl e s ol i ds ( s ugar ) 28- So r b i c aci d and s o r b at es 29- Sul phur di o xi de 30


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4. 3 P hy s i c al t es t s : 30- Ca l i b r a t i o n o f t he r mo me t e r s f or p r o c e s s i ng 30equi pment- Capac i t y of c ont ai ne r s 32- Dr a i ned mass 32- Doubl e seams 33- Equi l i br i um r e l at i ve hum di t y 46- Headspace o f canned f oods 50- Lacquer adhes i on 51- Lacquer coa t i ng mass 51- L ea k t es t s 52- Net mass 52- Ox y ge n p er me ab i l i t y 53- P i nhol e t e s t f or pa ck agi ng f i l ms 55- T emp er a t u r e o f f r o zen f o od s 57- T i n c o at i n g ma s s 58- Vac uum 58- Washed dr ai ned mass 58- Wa t e r v apo ur t r a ns m s s i o n r a t e 59

REFERENCES 60

ANNEX: STORAGE OF FRESH FRUI T AND VEGETABLES I NTENDED 61FOR PROCESSI NG


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C h a p t e r 1

INTRODUCTION

F r u i t a n d v e g e t a b l e p r o c e s s i n g i n d u s t r i e s p r o d u c e v e r y l a r g e q u a n t i t i e s o fprod ucts whi ch are intende d for co ns ump ti on, ofte n on a daily bas is, by thep o p u l a t i o n a t l a r g e . S u c h i n d u s t r i e s t h e r e f o r e h a v e a s p e c i a l r e s p o n s i b i l i t yto ens ure that their p rodu cts are both w hol eso me and sa fe , as well ass u c c e s s f u l i n t h e m a r k e t p l a c e .Thi s man ual is inten ded for use by proc esso rs of fruit and vege tabl eprod ucts as a guid e to the est abl ish men t and ope rat ion of soun dly based ande f f e c t i v e q u a l i t y c o n t r o l s y s t e m s . T h e m a n u a l d e a l s w i t h q u a l i t y c o n t r o l i nthe foll owin g types of fruit and veg eta ble pro ces sin g:. c a n n i n g ;. d e h y d r a t i o n ;. f r e e z i n g ;. p i c k l i n g , s y r u p i n g , c r y s t a l l i z i n g a nd c h e m i c a l p r e s e r v a t i o n .

In pre par ing the man ual it was acce pted that only limit ed reso urce s can bem a d e a v a i l a b l e i n a n y c o m m e r c i a l e n t e r p r i s e fo r q u a l i t y c o n t r o l . I t w a s a l s oreco gniz ed that at least a m inim um lev el of qua lit y con tro l is esse ntia lbeca use the produc ts of the fruit and veg eta ble pro ces sin g indus try areintend ed for huma n con sum pti on. The amoun t of a co mpa ny's reso urce s thatshould be g iven to qua lity cont rol ope rat ion s wil l vary acc ord ing to thenat ure of the product and pro ces s, the possi ble haz ard s as soci ated withd e f e c t i v e p r o d u c t s b e i n g p r o d u c e d a n d c o n s u m e d , a n d o t h e r f a c t o r s . I t w a salso reco gniz ed that the way qual ity contro l sys tem s are str uctu red and mannedvari es acc ord ing to the nat ure of the produ ct and proc ess and the size of them a n u f a c t u r i n g o p e r a t i o n . I n s o m e f a c t o r i e s e m p l o y i n g o n l y a fe w p e o p l e ,q u a l i t y c o n t r o l m a y b e o n l y o n e o f s e v e r a l r e s p o n s i b i l i t i e s o f a p a r t i c u l a rmemb er of staff but even in that sit uati on it is ess ent ial that an appr opri atel e v e l o f q u a l i t y c o n t r o l b e m a i n t a i n e d . I n l a r g e p r o c e s s i n g o r g a n i z a t i o n se m p l o y i n g h u n d r e d s o f p e o p l e , q u a l i t y c o n t r o l m a y b e t h e s o l e r e s p o n s i b i l i t yof a defin ed team . In view of the div ers e nat ure of ind ivi dua l facto ries inthe fruit and veg eta ble pro cess ing ind ust ry, it was deci ded that the manu alwould :

. d i s c u s s t h e p r i n c i p l e s o f q u a l i t y c o n t r o l s y s t e m sa p p r o p r i a t e t o f r u i t a n d v e g e t a b l e p r o c e s s i n g o p e r a t i o n s(chapter 2).

. d e s c r i b e h o w q u a l i t y c o n t r o l p r o c e d u r e s s h o u l d b e a p p l i e di n f r u i t a n d v e g e t a b l e p r o c e s s i n g o p e r a t i o n s ( c h a p t e r 3 ) .

. giv e det ail s of meth ods of exa min ati on and calib rat ion thatare appro pri ate for use in qua lit y cont rol in the fruit andv e g e t a b l e p r o c e s s i n g i n d u s t r y (chapter 4).


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Chapt er 2

ESTABLI SHI NG QUALI TY CONTROL SYSTEMS

2. 1 PRODUCTI ON PLANNI NGThe product i on of accept abl e, whol esome and saf e f r ui t and veget abl e product sdepends on t hr ee i nt er r el at ed f actors:

. speci f i cat i ons f or raw mat er i al s, t he pr oduct and t hepackagi ng sys t em must be based on t he r equi r ement s oft he i nt ended mar ket and t he r equi r ement s of r egul at or yaut hor i t i es ;. a product i on procedure must be desi gned to gi ve a pr oductwhi ch compl i es wi t h the speci f i cat i on and must be est abl i shedand pr operl y appl i ed;. A qual i t y cont r ol syst em must be est abl i shed f or moni t ori ngt he r aw mat er i al s, t he pr oduct i on procedur e and the f i nalpr oduct to ensur e, as f ar as possi bl e wi t h avai l abl e r esour ces,t hat t he pr oduct i s wi t hi n the speci f i cat i ons.The pr eparat i on of pr oduct speci f i cat i ons shoul d i nvol ver epr esent at i ves of market i ng, pr oduct i on and qual i t y cont r ol st af f andoccasi onal l y t he r esear ch and devel opment st af f . The mar ket i ng st af f shoul d

be abl e t o gi ve advi ce on what qual i t i es the pr oduct shoul d have i n order t omeet t he r equi r ement s of i ntended consumers. At t he same t i me t he pr oduct i onand t he qual i t y cont r ol st af f wi t h t he r esear ch and devel opment st af f shoul dbe abl e t o gi ve advi ce on how a product havi ng t hose qual i t i es can bepr oduced saf el y and r epeat edl y. The pr oduct i on and t he qual i t y cont r ol st af fshoul d al so i nt er act i n t he det ai l ed pl anni ng of t he pr oduct i on pr ocedur e andt he r el ated qual i t y cont r ol syst ems. I n t hi s way bot h gr oups unders t and whateach i s t r yi ng t o do and how t hei r r espect i ve t ask can be car r i ed out mostef f ect i vel y. Cl ear l y, i t i s i mpor t ant t hat t here be j oi nt pl anni ng of t hepr ocess bef ore pr oduct i on st art s and t hat t he pr oduct i on and qual i t y cont r olst af f r evi ew t hei r pr ocedur es as of t en as needed af t er pr oduct i on st art s toensure the pr oduct compl i es wi t h the agr eed speci f i cat i ons.I n smal l f act or i es wher e one person may be r esponsi bl e f or market i ng,pr oduct i on and qual i t y cont r ol , t hat per son shoul d assess the whol epr oduct i on oper at i on as descri bed above; i . e. f i r st l y devel op speci f i cat i onsf or t he r aw mat er i al s and product , then deci de how t he product wi l l bemoni t ored.

2. 2. I NTERACTI ON OF QUALI TY CONTROL AND PRODUCTI ON STAFF DURI NG PRODUCTI ONThe cl ose col l aborat i on bet ween qual i t y cont r ol and pr oduct i on st af f , whi chi s so i mpor t ant duri ng t he pl anni ng of t he manuf act ur i ng pr ocess, shoul d becont i nued when t he pr ocess i s put i nt o operat i on. Thi s r equi r ement i spr obabl y more per t i nent i n t he f r ui t and veget abl e pr ocessi ng i ndust r y t han


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i n mo st o t h er i ndus t r i e s be c aus e f ew a t t r i but e s of t he se p r o d uc t s a r eamenab l e t o obj ect i ve measur ement and f ewer s t i l l o f t hese measur ement s canbe aut omat ed. Much r e l i ance mus t t her e f or e be p l aced on subj ect i vea s s e s s me nt s i n e f f o r t s t o e ns ur e t hat t he ma nuf a c t ur i ng pr o c es s i s o pe r a t i ngpr ope r l y and t he pr oduc t i s s a t i s f a ct o r y . I t f ol l ows t h at t h e e f f e ct i v ene s sof qua l i t y cont r o l i nc r eas es as t he n umb er of peop l e obs e r v i n g t he pr oduc tand pr oces s i n c r eas es . Cl ear l y t he r e a r e adv ant ages i nv o l v i n g ev er y on e wh oi s i n cont ac t wi t h t h e pr oduc t and p r oces s i n s ome as pec t o f qu al i t y cont r o l .F or ex amp l e , peop l e ope r a t i n g can c l o s er s s h oul d i ns p ec t t he l oos e ends t oc onf i r m t hat t hey a r e c o r r e c t l y f o r me d, t he c ompo und i s pr o pe r l y di s t r i but e dand t hat t he ends ar e t he t ype r equi r ed f o r t he p roduct bei ng packed. Thec l o s er o pe r a t o r s s houl d a l s o c he c k t he c a nne r ' s do ubl e s ea m as o f t e n asp os s i bl e f or d ef ec t s s u ch as d r oops , s p ur s o r cu t ov e r s ( s ee " Doubl e s eams "p. 33) .

The i nv ol v ement of p r od uc t i on p er s on ne l i n s ome as pec t s of qua l i t ycont r o l i s cont r a r y t o s ome management concept s i n wh i ch d i f f e r ent f un c t i onswi t hi n t he o r g a ni z a t i o n a r e c o mpa r t me nt a l i z e d. T he s e f o r ms of o r g ani z a t i o na ls t r uc t u r e cl ear l y s epar at e r es pons i bi l i t i es f or pr oduc t i on and qual i t yc ont r o l . Ho we ve r , f or t he f r u i t and v ege t a bl e pr o ce s s i ng i ndus t r i e s t h i ss epa r a t i on i s a h i n dr ance t o ens u r i n g t ha t t he manu f ac t u r i n g pr oces s i so pe r a t i ng s a t i s f a ct o r i l y and t hat t h e f i nal pr oduc t c ompl i e s wi t h i t ss pec i f i c at i on. The pr e f er r e d or gani z at i ona l s t r uc t u r e t her e f or e r e qui r e ss o me o ve r l a p of t he r e s po ns i bi l i t i e s of t he pr o duc t i o n and qua l i t y c o nt r o ls t a f f . The mos t i mpor t ant advant ages of t hi s a r r angement ar e that t he numberof de di c a t e d o bs e r v e r s on t h e pr o duc t i o n l i ne i s i nc r e as e d and de vi a t i o nsf r om t he no r m i n t he pr o c es s or pr o duc t s ho ul d be de t e c t e d and r e po r t e d wi t hm ni mum del ay.

E ven t hough t h e r ecommend ed o r g ani z a t i ona l s t r u c t u r e f or q ua l i t yc o nt r o l and pr o duc t i o n i n f r ui t and v ege t a bl e pr o c es s i ng f a c t o r i e s r e qui r e sc l o s e c o l l a bo r a t i o n be t we en t he t wo gr o up s , i t i s a l s o e s s e nt i a l t hat t heybo t h r epo r t d i r ec t l y t o and hav e equ al s t a t u s wi t h management . Thi sr e qui r e me nt i s e s pe c i a l l y i mpo r t a nt whe n a c o nf l i c t of o pi ni o n o c c ur s . F ori n s t ance , qu al i t y cont r o l p er s onn el may cons i d er t hat a pr oduc t does no tc ompl y wi t h t he s p ec i f i c a t i o n whi l e pr o duc t i o n p er s o nne l wi s h t o c o nt i nuepr o c es s i ng; t h i s t y pe of pr o bl e m s ho ul d be r e f e r r e d t o ma na ge me nt f or adec i s i on.

2. 3 ALL OCATI ON OF RESOURCES TO QUAL I TY CONTROLManagement i s r espons i b l e f o r dec i d i ng how much of t he or gan i zat i on' sa va i l a bl e r es our c es ar e gi v en t o qua l i t y c ont r ol . T hi s de ci s i on woul d bei nf l uenc ed by t he r e qui r e me nt s of s t at ut o r y aut ho r i t i e s , e. g. t h e a ut ho r i t i e smay r equ i r e a canner t o meas u r e t he concent r a t i on of ch l o r i ne i n r e t o r tcool i ng wa t e r s o he woul d h av e t o p r ov i d e app r op r i a t e s t a f f and equi p ment .The dec i s i on woul d a l so have to be based on a j udgement o f t he p rot ect i onaf f or ded by e s t a bl i s hi ng a par t i c ul ar l ev el of qua l i t y c ont r o l c ompar ed t ot he p os s i bl e r i s k s t o cons u mer s , t o t he p r oces s o r ' s r epu t a t i on and pe r h apse ve n t o t he i ndus t r y ' s r e put a t i o n i f f aul t p r o duc t s r e ac he d t he ma r k e t . T her i s k s v ar y a c c or di ng t o t he na t u r e of t he pr o duc t , t he r e qui r e me nt s of t hemar ke t and o t he r f ac t o r s and t hey a r e i mpos s i b l e t o q uant i f y . I t mus t a l s obe accept ed, i n dec i d i ng how much o f t he company ' s r esour ces shoul d be g i vent o qua l i t y c ont r ol , t h at e ve n t h e mos t e l a bo r a t e qua l i t y c ont r ol s ys t em wi l lno t gi v e abs o l u t e as s u r an ce t ha t onl y accept abl e pr odu c t s r each t he mar ke t .Management must al so be awar e t hat t he absence of consumer compl ai nt s doesno t mean t hat a q ua l i t y cont r o l s y s t em i s u nn eces s a r y ; i t may mean t hat t he


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sy s t em i s i ndeed e f f ec t i v e; i t may mean t hat by good ma nu f a c t u r i ng pr a ct i c eand good l uck no def ect i ve pr oduct s r eached t he mar ket or i t may mean t hatconsumer s s i mpl y f a i l ed to compl a i n .As t he r es our c es avai l abl e f o r qual i t y c ont r ol ar e us ual l y l i m t ed t heyshoul d be di r ect ed t o moni t or i ng t hose poi nt s whi ch ar e j udged t o be moste f f e ct i v e i n ens ur i ng t hat t h e f i nal pr oduc t c ompl i e s wi t h i t ss p ec i f i c at i o ns . T he s e poi nt s f al l i nt o t wo br oad a r e as :. t he manuf ac t ur i ng process wh i ch s t a r t s wi t h t he procur ement of r awmat er i a l s and ends wi t h the despat ch o f t he f i ni shed pr oduct t o t hemar ket ;. t he env i r onment i n wh i ch t he manuf ac t ur i ng process i s car r i ed outwh i c h i nc l udes gener a l housek eepi ng, c l ean i ng, sa ni t a t i o n andc al i br at i on of c ont r ol i ns t r ument s .

2.4 MONITORING THE MANUFACTURING PROCESS

The number and pos i t i on of t he poi n ts i n t he manuf acur i ng process ( i nc l udi ngt he procur ement of r aw mat er i a l s ) t hat shou l d be moni t o red wi l l al so var ya c c or d i ng t o t he a ssessment of po t en t i a l ha zar ds i f at t hat po i nt t he p ro c essdev i a t es f r om t he nor m T he po i nt s t o be mo ni t o red wi l l depend on t he na t u r eof t he product and process as we l l as t he r esour ces ava i l abl e . The f r equencyand pl a c es of mo ni t o r i ng shoul d be se l ect ed j o i n t l y by t he qual i t y c ont r o land pr o duc t i on s t af f . T he pr o cedur e f or es t abl i s hi ng t he qua l i t y c ont r olr egi me i s so met i mes based on t he haza rd a na l y s i s c r i t i c a l c o nt r o l poi nt( HACCP) concept . The t r adi t i onal emphasi s of t he HACCP concept has t ended tobe t he c ont r o l of m c r obi ol o gi c al h az a r d s but t he c onc ept i s a ppl i c abl e t omo ni t o r i ng o t her a t t r i bu t es of t he pr o duc t t hat ma y det e rm ne i t sa cc e pt a bi l i t y , e. g. , net wei ght , dr ai ned we i ght or c ompo s i t i on of t h epr o duc t . T he s e l e ct i o n of c r i t i c al c ont r ol poi nt s s houl d be r evi ewed atr egul a r i nt e rv a l s and c hanged i f expe r i enc e shows t hat t he sy s t em c oul d bemade mor e ef f ect i ve; moni t or i ng of some poi nt s may be di scont i nued or t hef r equency of moni t o r i ng may be changed. I n many i ns t ances t he c r i t i ca lpo i nt s wi l l al r eady be s t af f ed and under t h e s uper v i s i on of pr o duc t i o n s t af f .The HACCP concept shoul d t heref or e be used as a gui de f or obt ai ni ng maxi mumbenef i t f r o m t he av ai l abl e r es our c es f o r qual i t y cont r ol .

2.5 MONITORING THE MANUFACTURING ENVIRONMENT

Qua l i t y c ont r o l s t af f s houl d al s o be r es pons i bl e f or mo ni t o r i ng t h eenv i r o nment of t he ma nu f a c t u r i ng pr oc ess beca use f a c t o r s not di r ect l yi nv ol v ed wi t h t he pr o c ess ma y a f f ect i t s e f f i c i enc y and t he qua l i t y ands af et y of t he f i nal p r oduc t . Thes e r es pons i bi l i t i es i nc l ude:

. moni t o r i ng ac t i on t a ken t o pr event i nf e s t a t i on of t he pr o ce s s i ngpl a nt by i nsec t s , bi r ds and ani ma l s ;

. a s sess i ng t he e f f ec t i v eness o f c l eani ng and sa ni t i z i ng pr o gr a mmes .

. det e rm n i ng t hat pe r so nne l ar e c l ean , i n good heal t h and dr essedi n appr opr i a t e gar ment s ;

. ensur i ng t hat s t o r age a reas ar e c l ean and t i dy and have appr opr i a t et empera t ur es and hum d i t i e s ;


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. i ns pec t i ng f i el d bi ns f or c l eanl i nes s and s t at e of r epai r ;

. det er m ni ng t hat was t e di s pos al s ys t ems a r e oper at i ng s a t i s f ac t o r i l y;

. c al i br a t i ng c ont r ol and i ndi c at i ng i ns t r ume nt s on pr o ce s s i ngequ i pment such as r e t o r t s ;

. r espondi ng to consumer compl a i n t s .

2.6 END-PRODUCT TESTING

T he a mo unt o f qual i t y c o nt r o l e f f o r t a ppl i ed t o end - p ro duc t eva l uat i o n, onc ea r e l i a bl e and e f f ec t i v e ma nu f a c t ur i ng pr o cess ha s been es t a bl i shed , shoul dbe sma l l compared t o t he r esour ces g i ven t o moni t o r i ng t he process i t se l f .T es t s on t he e nd- pr oduc t gi v e i nf o r mat i o n whi c h i s l ar gel y of hi s t o r i c v al ue ,wher eas moni t o r i ng o f t he process shoul d g i ve an ear l y war n i ng of a f aul t sot hat co r r ec t i ve ac t i on may be t aken bef o r e unnecessar i l y l a rge amount s ofma t e r i a l s and t i me a re wa s t ed. Anot her adva nt a ge of i n - p ro c ess i n spec t i o n,espec i a l l y wher e p ro duc t i o n pe r s o nne l a re a c c ep t i ng so me r espo ns i b i l i t y f orqua l i t y c ont r ol , i s t hat a l l t he pr oduc t i s bei ng wat c hed by t he oper a t i v es .I n c o nt r a s t , end- p ro duct i nspec t i o n r equi r e s sa mp l i ng of t he p ro duct i o n andt hi s i s a ma j o r i mpedi ment t o de t ec t i ng f a ul t y ma t e r i a l .

Any pr a c t i c a l sa mpl i ng p ro c edure i s next t o usel e s s when t he t ol e ra nc ef or de f ec t s i n f oods , and e s pe ci al l y ha z ar do us de f e ct s , i s e xt r eme l y l ow. I ti s o f t en assumed t hat sampl i ng procedur es t hat a r e based on s t a t i s t i ca lt heor y g i ve a t r ue assessment of t he qua l i t y of a bat ch and t hat suchpr o c edures a l wa ys de t ec t def ec t i v e uni t s wi t h i n t he ba t c h . I t mus t beempha s i zed t hat sa mp l i ng a c c or d i ng t o a s t a t i s t i c a l pl a n do es not of f e r am r ac ul ous sol ut i on t o t he pr o bl em of l oc at i ng def ec t i ve uni t s ; per h aps t hemo s t i mpo r t a nt a dv an t a ge t o s t a t i s t i c a l sa mpl i ng i s t hat unde r def i nedc o nd i t i o ns i t gi v es a measu re of t he e f f i c i enc y of t he sa mpl i ng r egi me . F ore xa mpl e , i f 0 . 5% of t he r andom y di s t r i but e d uni t s i n a l ar ge bat c h we r edef ec t i v e and t en sa mpl es we re t ak en at r a ndom t her e i s a 95% c ha nc e ofm ss i ng a f aul t y un i t ; 20 sa mp l es wo ul d g i v e a 90% c ha nc e of ac c ept i ng t hebat ch and even 200 sampl es woul d not cont a i n a def ect i ve uni t on an aver ageof about one i n t hr ee occas i ons . Such f i gur es may be ca l cu l a t ed us i ng t heequat i o n:p = [ ( 100 - x ) / 100 ] n

whe r e p i s t he pr obabi l i t y of f ai l i ng t o f i nd at l eas t o ne def e ct i v e uni t byt ak i ng a r andom s a mpl e o f n uni t s when t he f r ac t i on ( %) of r andom ydi s t r i but ed def ec t i ve uni t s i s x. Cl ear l y, pr ac t i c al l evel s of s ampl i ng wi l lbe r el i abl e onl y when a l ar ge f r ac t i on of t he bat c h i s def e ct i v e. Sampl i ngmay be even l ess e f f i c i ent t han t hese f i gur es i ndi ca t e because i n manyi ns t a nc es t he def ec t i v e uni t s may not be r a ndo m y d i s t r i but ed.

2.7 INCIDENCE OF DEFECTIVE PRODUCT

Re ga r d l e s s of t he e f f ec t i v ene s s of qua l i t y c ont r ol and pr o duc t i on p r o c edur es ,s mal l a mo unt s of d ef e ct i v e pr oduc t s us ual l y o cc ur i n o t h er - wi s e s at i s f ac t or yma t e r i a l . T he s e f aul t y pr oduc t s ar e of t en di s c ar ded wi t ho ut i nv es t i gat i on byt he manuf ac t urer because i t i s no t r eal i zed that changes i n t he i nc i dence ofdef ect i ve pr oduct s and knowl edge of t he cause of t he def ect s may war n t hema nuf a ct ur e r t h at t he pr o ces s i s about t o f ai l . F or i ns t anc e, an i nc r e as e i nt he number of cans showi ng post - pr ocess i ng cont am nat i on may i ndi ca t e t hat


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t he qua l i t y of t he c ans ha s de t e r i o r a t e d, t hat t he c a nne r ' s s e am ha s de pa r t e df r om s p ec i f i c a t i o n, o r t hat t he c ans we r e c o nt a m na t e d by t he c o ol i ng wa t e ror du r i n g t he h an dl i n g ope r a t i ons a f t e r coo l i n g. The weakn es s i n t he cann er yoper a t i on s houl d be i dent i f i ed and co r r ec t ed b ef o r e t he n umb er o f s p oi l edcans exceeds t he usual m n i mum number wh i ch occur even wi t h goodma nuf a c t u r i ng pr a c t i c e .

2. 8 TREAT MENT OF QUAL I TY CONTROL DATAQua l i t y co nt r o l d at a t hat r el at e t o t he l ong- t er m a cc ept a bi l i t y and s af et y oft he pr oduc t s houl d be r ecor ded i n de t a i l and t he r ecor d s s h oul d a l l ow r eadyi d ent i f i c a t i o n of t he a ppr o pr i a t e ba t c h of t he pr o duc t . Suc h r e c or ds s ho ul dbe r e t a i ne d f or a per i o d i n e xc e s s of t he us u al c o mme r c i a l l i f e of t h epr o duc t ; wi t h pr o ce s s ed f r ui t s and v ege t a b l e s ; t hr e e y ea r s i s pr o ba bl yadequ at e . The ma i n us e of t hes e r ecor ds i s t o as s i s t i n r es pond i n g t ocomp l a i n t s about t he p roduct when i t r eaches t he mar ket o r t o he l p i ni nv es t i ga t i ng t he c a us e of de f e c t s i f t hey a r e de t e c t e d i n wa r e ho us e s t o c ks .

The r e a r e adv ant ages i n g r ap hi n g s ome q ua l i t y con t r o l d at a i n o r d er t odi s c er n s hor t t e r m t r ends i n t h e pr o ce ss or pr o duc t . Can s ea m di me ns i o ns ,i nc i de nc e of l e ak y c a ns , o r net we i ght s a r e o f t e n pl o t t e d o n c o nt r o l c ha r t sor x c ha r t s ; i . e. t he me as ur e d v al ue s a r e pl o t t e d o n t he v er t i c a l a x i s . T hedes i r ed v a l u e may b e i ndi ca t ed on t he g r ap h by a h o r i z on t a l l i ne ando pe r a t i ng l i m t s a bo ve and bel ow t h at v al ue ar e s i m l a r l y i ndi c at ed ( f i gur e1 ) .Anot her s i mp l e met hod of t r eat i ng t hese t ypes o f dat a , but one wh i chus ual l y gi v es ear l i er wa r ni ngs of dev i at i ons f r o m a des i r ed val ue, i s t o pl otcumu l at i ve sum ( CUSUM) char t s . The d i f f e r ence bet ween t he measur ed va l ue andt he r e qui r e d v al ue i s c a l c ul a t e d and t he se di f f e r e n c es a r e pl o t t e d a s acumu l at i ve t o t a l aga i ns t t i me or t he number o f t he samp l e . F i gur e 2 was

obt a i ned by p l o t t i ng t he dat a i n F i gur e 2 as a CUSUM char t and t he r esu l t antl i ne i ndi c at e s t h at af t er t h e f i r s t f i v e o bs e r v at i o ns t her e i s a ge ne r a lupwar d t r end.Bot h cont r o l char t s and CUSUM char t s may be used s i mpl y as p i ct ur ess h owi n g t r ends i n qu al i t y cont r o l pa r amet e r s . Un der t h es e c i r cu ms t ances t hede ci s i o ns about ac t i o n t o be t ak en i n r es pons e t o de vi a t i o ns f r o m des i r edv al ue s a r e l ar gel y s ubj e ct i v e but no ne t h el e s s us e f ul . Be t t e r bas ed de ci s i o nsmay be made i f s t a t i s t i ca l met h od s a r e appl i ed i n d ev e l opi n g t he ch ar t s andi n ass ess i ng t r ends ; t hese met hods are descr i bed i n some s t andar d t ex t s ons t at i s t i c s.

2. 9 STAFF / MANAGEMENT RELATI ONST he s y s t e m of qua l i t y c o nt r o l r e co mme nde d f or t he pr o c es s e d f r ui t andv eg et a bl e i ndus t r y r e qui r e s c o l l a bo r a t i o n be t we en ma r k e t i n g, pr o duc t i o n andqua l i t y c o nt r o l s t af f d ur i ng pl a nni ng of t he pr o c es s , and be t we en pr o duc t i o nand qua l i t y c o nt r o l p er s o nne l dur i ng pr o duc t i o n. T hi s i n t ur n r e qui r e s s o meov er l ap or b r eakdown of t he b oun dar i es t hat s epa r a t e t hes e f u nc t i ons i nc o nv ent i o na l l y s t r uc t ur e d ma nuf a c t u r i ng o r g a ni z a t i o ns and t hat r e qui r e s t hesuppor t and encour agement of management . Each depar t ment must al so havedi r ect and i ndependent acces s t o management .


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LUZD IOU ScuI DCO


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T I ME OR N U MBER O F T H E SAM PL EF i g ur e 2. A CUS UM cha r t p l o t t ed f r om t he d at e i n

F i gur e 1. T hi s c har t i ndi c at e s a pr o ba bl eupwar d t r end wh i ch i s no t ob v i ous i n F i g ur e


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T he s u c c es s f u l o pe r a t i o n of qua l i t y c on t r o l s y s t e ms f o r pr o ce s s ed f r ui t s andv e ge t a bl e s r e qu i r e s ma na ge me nt t o e nc o ur a ge pe r s o n ne l at a l l l e ve l s t o r e po r tdev i at i ons f r o m t h e es t abl i s hed pr oc es s or def ec t s i n t he pr oduc t . Anyd i s i n c en t i v e t o r epor t r e al or a ppa r e nt pr o bl e ms may r e s ul t i n d ef e c t i v epr oduc t s r each i ng the mar ke t wh i ch may have consequences r ang i ng f r om l oss ofsa l es t o the dea t h o f consumer s .


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Chapt er 3

QUALITY CONTROL SYSTEMS FOR FRUIT AND VEGETAB LE PROCESSING

T he pr o c es s i ng of f r ui t s and v e ge t a b l e s i nv ol v es s e ve r a l s t e ps or uni to pe r a t i o ns whi c h s t a r t wi t h t he pr o c ur e me nt of t he r aw ma t e r i a l . F ol l o wi ngp r e pa r a t i v e t r e at me nt s s uc h a s c l e ani ng, pe el i ng, bl a nc hi ng a nd m x i ng; t hep r oduc t i s p r oces s ed and packaged t o g i v e t he r equ i r ed f i ni s h ed pr odu c t . Thema nuf a c t ur i ng pr o c es s e s f al l i nt o f our g r o ups :

. c a nni ng;

. de hy dr a t i o n;

. f r e ez i ng;

. pi c kl i ng, s yr upi ng, c r y st a l l i z i ng and c hem c al pr e s er vat i on.

3.1 RAW MATERI ALST he r a w ma t e r i a l s f or t he f r u i t a nd v ege t a b l e pr o c es s i ng i ndus t r y i nc l ude :

. f r ui t s and v ege t a bl e s ;

. s uga r , s al t , s pi c es , f ood ac i ds and ot her m no r i ngr e di e nt s ;

. wa t e r and s t eam

. c ont a i ne r s , l abel s and pac k agi ng ma t e r i a l s ;

. de t e r ge nt s and s ani t i z e r s .

Fruit and VegetablesQua l i t y c o nt r o l s t a f f s ho ul d be c ome f a m l i ar wi t h t he pr a ct i c e s i nv ol v ed i ng r o wi n g, ha r v e s t i ng and t r a ns po r t i ng t he f r ui t s and ve ge t a b l e s t o t hepr o c es s i ng f a ct or y .Fi el d Pr ac t i c es : Qual i t y c ont r ol s t a f f s houl d de t e r m ne what agr i c ul t ur a lchem cal s ar e used by gr ower s and how and when t hey ar e appl i ed t o t he cr op.Onl y pr oduce t hat has been gr own under approved condi t i ons ( and t hat compl i eswi t h t he pr o ce s s or ' s s pe ci f i c at i o ns f or t he r a w ma t e r i a l ) s houl d be a cc ept edf or pr oc es s i ng bec aus e i t i s s el dom f eas i bl e t o anal y se r a w f r ui t s andv ege t a bl e s f or r e s i dua l s of agr i c ul t ur a l c he m c al s be f or e t he c ons i gnme nt i sp r oces s ed .

The g r owi ng ar eas shoul d a l so be i nspect ed t o ensur e t hat t he r awf r ui t s and v eg et a bl e s a r e not c ont a m na t e d wi t h o t h er po t e n t i a l l y ha z ar do usma t e r i a l s s uc h as t oxi c wa s t e wa t e r or ga s eo us e m s s i o ns f r o m ne i ghbo ur i ngi ndus t r i es .


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- 11 -Ma t u r i t y of f r ui t s and v eg et a bl e s . T he qua l i t y of ma ny pr o c es s e d f r ui t s andv ege t a b l e s i s ma r k e dl y i nf l ue nc e d by t he p hy s i o l o gi c a l ma t u r i t y of t he r awma t e r i a l s at t he t i me of ha r v e s t . T he ma t u r i t y of f r ui t s and v ege t a bl e s i so f t e n de t e r m ne d by v i s ua l i ns pec t i o n and f r om t h e t ac t i l e pr o pe r t i e s of t hep r o d uc t s but ob j e c t i v e me t h od s a r e a l s o u s ed . F or e x amp l e , t he ma t ur i t y o fs we et c or n i s r e l at e d t o i t s mo i s t u r e c o nt e nt , r e f r a c t i v e i nde x and t o t heS uc c u l o me t e r r e adi ng ; t he ma t u r i t y of g r e en pe as i s i nd i c a t e d by t he c o nt e nto f a l c o ho l i n s ol u bl e s o l i ds a nd by t he r e ad i n gs o f s u c h i n s t r u me nt s a s t heF . M. C. T end e r o met e r , Ma t u r o met e r o r Ot t a wa T ex t u r e Mea s u r i n g S ys t em T heE f f e - g i and Ma gn es s - T a yl o r p r e s s u r e t e s t e r s a r e us e d t o me a s ur e t h e ma t u r i t yof s o me p ome a nd s t o ne f r ui t s and s u ga r / a c i d r a t i o s i n di c a t e t he ma t u r i t y ofc i t r us f r ui t s ( f or a na l y t i c a l me t h o ds s ee " C he m c a l a na l y s e s " p. 20 a nd Kr a me rand Twi gg , 1962) .T r a ns po r t of f r ui t s and v ege t a bl e s . T he qua l i t y of t h e f i nal pr oduc t i s of t e ni n f l u en ced by t he wa y t h e r a w f r u i t s and v ege t a b l e s a r e h ar v es t ed a nd ha nd l eddur i ng t r ans por t f r om t h e gr o wi ng a r e a t o t h e f a ct or y . Qua l i t y c ont r o l s t af fs h oul d i ns p ec t t he s e o pe r a t i o ns t o e ns u r e t hat t he r a w ma t e r i a l s a r e ha nd l e dc a r e f u l l y t o m n i m z e me c ha ni c a l d ama ge . T he s e p r o d uc t s s h oul d bet r a ns po r t e d i n c l e an, p r o pe r l y c o ns t r uc t e d bi ns or o t h er a ppr o pr i a t ec o nt a i ne r s wi t ho ut de l a y t o t he pr o c es s i ng pl a nt . L o ads of r aw f r ui t s andv ege t a bl e s s ho ul d be c o ve r e d dur i ng t r a ns po r t f or pr o t e c t i o n f r om t he s un,r a i n a nd co n t a m n at i o n. S ome v ege t a b l e s , s u ch a s g r een p ea s a nd a s p a r a g u swhi c h a r e pr o ne t o r a pi d s e l f - he at i ng and d et e r i o r a t i o n i n qu al i t y , s ho ul d behy dr o - c o ol e d or i c ed i f t he de l a y be t we en ha r v e s t i n g and pr o c es s i ng i s l i k el yt o be l onger t han a f ew hour s .St o r a ge of r a w f r ui t s and v ege t a bl e s . Qua l i t y c o nt r o l s t a f f s houl d a l s oi ns pe c t t he r a w f r ui t s a nd v e ge t a bl e s d ur i n g s t o r a ge at t he p r o c e s s i n g pl a ntt o en s ur e t hey a r e :

. p r o t e c t e d f r om a t t a c k by r o de nt s and i ns e c t s ;

. s t o r e d unde r s u i t a bl e c o ndi t i o ns of t e mpe r a t ur e and hum d i t y f orp er i o ds wh i c h do no t al l o w e x c es s i v e d et e r i o r a t i o n ( s e e An ne x " A" ) ;

. ha ndl e d c a r e f ul l y t o m ni m z e me c ha ni c a l da ma ge .

Sugar, salt, spices, food acids and other minor ingred ientsT h es e ma t e r i a l s ma y a l s o h av e a ma r k ed e f f ec t o n t he q ua l i t y a nd s a f e t y o ft he f i ni s he d pr o duc t s o qua l i t y c o nt r o l s t a f f s ho ul d r e qui r e t hes ei ngr e di e nt s t o be o bt a i ne d f r om r e put a bl e s u pp l i e r s and t he ma t e r i a l s s ho ul dbe of at l eas t " f ood gr a de " qua l i t y . I f po s s i bl e qua l i t y c ont r o l s t af fs ho ul d v i s i t s upp l i e r s t o s a t i s f y t he ms e l v es t h at t he se i t e ms a r e pr o duc e d,pa c ke d and s t o r e d u nd er c o nd i t i o ns o f go od ma nu f a c t u r i n g pr a c t i c e . Ag ai n i ti s s el dom pos s i bl e f or qual i t y c ont r o l s t a f f t o a nal y s e s uc h mat e r i a l s f orpur i t y o r f or t he p r e s e nc e o f any of a l a r g e n umb er o f p o t e nt i a l l y d a ng er o usc ont a m na nt s .I ns pe ct i o n on r e ce i v al . Qua l i t y c ont r o l s t af f s houl d i ns pec t a l lc o ns i gnme nt s of i ngr e di e nt s o n r e c ei pt t o c o nf i r m t hat t hey c o mpl y wi t h t hec ompa ny ' s pur c ha s i ng s pe ci f i c at i o ns . I f r e s our c es a r e l i m t ed t h e qua l i t yc ont r o l s t af f may r e st r i c t t he i ns pe ct i on t o t he e s s ent i a l m ni mum of :

. c o nf i r m ng t hat t he ma t e r i a l s de l i v er e d a r e t he o ne s o r d er e d ( e . g.s a l t s ho ul d be c o nf i r me d t o be s a l t and no t a no t h er wh i t e c r y s t a l l i n e


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s u bs t a nc e ) ;. det er m n i ng t hat t he cons i gnment was not damaged or c ont am nat ed t ot he e xt e nt t hat t he ma t e r i a l s a r e not s ui t a bl e f or t hei r i nt endedused.Ac c e pt a nc e t es t i ng ma y r e qui r e s i mpl e c he m c a l t e s t s , e . g. t o de t e r m net he c onc e nt r a t i o n of ac et i c ac i d i n v i negar ( s ee " Ac i di t y " , p. 20) , or t hei ngr edi ent may have to be used i n t he p r oduct i on o f a smal l bat ch of t hepr o duc t t o t es t t h at i t i s s a t i s f a ct o r y , e. g. t o as s es s t he po t e nc y ofs pi c es .Mi c r o bi o l o gi c a l t es t s of i ngr e di e nt s f or t he ma nu f a c t u r e of pr o ce s s edf r ui t a nd v ege t a b l e pr o duc t s a r e s e l do m wa r r a nt e d. Ho we ve r , i t i s pr ude nt t ol i m t t he numbe r o f t he r mo phi l i c s po r i ng ba c t e r i a t hat ma y be i nc o r p or a t e d i nl ow- ac i d canned p roduct s such as soups t h rough t he use o f cont am nat edi ngr e di ent s s uc h as t hi c keni ng a gent s or dr y s pi c es , e spe ci al l y i f t hes epr o duc t s ar e i nt e nde d f or di s t r i but i o n t o hot c l i ma t e s . Mo ul dy ma t e r i a l ssuch as dr i ed peas and beans must not be accept ed as i ngr ed i ent s because of

t he r i s k of af l at oxi ns . I t i s s el dom f eas i bl e t o t es t moul dy mat er i al f ors uc h t ox i c s u bs t a nc e s ; a l t ho ugh r e l a t i v el y s i mpl e me t h ods of de t e c t i o n a r eav ai l a bl e ( s ee " Af l at ox i ns " , p. 21) .

Vat er and s t eamQua l i t y and di s t r i but i o n of wa t e r . Wa t e r o f v ar i o us qu al i t i e s may be us ed atd i f f e r ent po i nt s i n mos t f ood p r oces s i ng ope r a t i ons and i t i s common f orwa t e r t o be r e us e d. Wa t e r wi t h o bv i o us t ur bi di t y i s o f t e n s a t i s f a c t o r y f ors o ak i ng r o ot v ege t a bl e s or f or f l um ng f r u i t whi c h i s t o be c he m c al l ypee l ed, but onl y wat er wh i ch i s sui t abl e f o r human consumpt i on shoul d be usedf or t he f i na l wa s hi ng of t he pr oduc t o r a s an i ngr e di e nt , e . g. i n br i ne s ors y r u ps . Onl y pr ope r l y chl o r i na t ed c l ean wa t e r s h oul d be us ed f or cool i ngc anne d pr o duc t s a f t e r t he hea t s t e r i l i z a t i o n pr o c es s .

Qua l i t y c ont r o l s t af f s houl d i ns pec t wa t e r s uppl y and di s t r i but i o ns y s t ems t o ens u r e t hat onl y wa t e r of an app r op r i a t e q ua l i t y i s be i n g u s ed,and t hey s ho ul d r e gul a r l y c he ck t he c o nc e nt r a t i o n of f r ee r e s i dua l c hl o r i nei n t he c hl o r i na t e d wa t e r s uppl y at t he po i nt s of us e ( s ee " Chl o r i ne i nwa t e r " , p. 24) . Wat e r l i nes s houl d be pur ged be f o r e p r oces s i n g ope r a t i onss t a r t t o e ns ur e t hat o nl y wa t e r o f t he r equi r e d qua l i t y i s be i ng de l i v er e d.

St eam qua l i t y . St eam al s o c omes i nt o c ont ac t wi t h f r ui t s and v ege t a bl e s i ns ome p r oces s i n g ope r a t i ons . Thes e i nc l ude s ome l y e - p ee l i n g s y s t ems ,s t eam- h ea t ed exhaus t boxes , s t eam- f l ow c l o s e r s , s t eam b l anch er s , and wa t e rbl a nc he r s whi c h a r e he at e d by di r ec t i nj e ct i o n of s t e am Qua l i t y c o nt r o ls t a f f s ho ul d de t e r m ne t hat e i t he r t he s t e am t hat c o me s i nt o c o nt a c t wi t h t hepr o duc t i s not c o nt a m na t e d by boi l e r a ddi t i v es or t hat t he a dd i t i v es ar e noth ar mf u l , or bo t h . Qua l i t y c o nt r o l s t a f f s houl d a l s o e ns u r e t hat c o nde ns a t eand t he p r oduct s of cor r os i on t hat may accumu l at e i n t he p i pewor k o f t hes t e am d i s t r i b ut i o n s y s t e m dur i ng s hut - do wns a r e r e mo ve d by pur gi ng t he s ys t embe f o r e f ood pr o ce s s i ng o pe r a t i o ns s t ar t . I t i s a l s o i mpor t ant t o de t e r m net h at s t eam t r aps and s t r a i ne r s a r e ma i nt ai ned i n good c ondi t i o n t o hel pe ns ur e t h at c l e an s t e am i s del i v er ed t o pr o ce s s i ng poi nt s .


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Co nt a i ne r s , l a be l s and pa c ka gi ng ma t e r i a l sQua l i t y c o nt r o l s t a f f s ho ul d i ns pe ct e ac h c ons i gnme nt of co nt a i ne r s , l a be l sand p ackagi ng mat e r i a l s t o ens u r e t hat t hey a r e d el i v er ed i n good condi t i onsand t hat t he i t ems c ompl y wi t h t he pur c ha s i ng s p ec i f i c a t i o n. I n a ddi t i o n,s a mpl e s of p r i ma r y c ont a i ne r s ( c ans , d r ums , gl a s s j a r s , f l e xi bl e po uc he s andbags and s em - r i gi d al um ni um t r ay pa c ks ) s houl d be ex am ned t o de t e r m net hat t he pr o pe r t i e s of t hes e i t ems t hat a r e c r i t i c a l t o t h e s a f e t y ands t o r a ge s t a bi l i t y of t he pr oduc t a r e s at i s f a ct or y .Cans . Samp l es of cans s houl d be exam ned t o d et e r m n e t hat t he f o l l owi ngf eat ur e s ar e wi t hi n s pec i f i c at i ons :

. t he d ou bl e s eam ( s ee " Doubl e s eams " , p. 3 3) ;

. t he s i de seam and f l ange o f t he open end ;

. t he t y pe and coat i ng mas s o f i nt e r n a l l a cqu er s , and t he i r cov er ageand degr ee of adh es i on ( s ee " L acquer adh es i on" , p. 51 ) ;

. t he t i n c o at i ng ma s s ( " T i n c o at i ng ma s s " , p. 58) ;

. t he s t r uct ur e of t he l oose ends and t he p l acement and amount ofcompound.Some cans shoul d a l so be f i l l ed wi t h wat er and c l osed so t hat t hecann er ' s d ou bl e s eam may be as s es s ed ( s ee " Doubl e s eams " , p. 33) . I f t hes eams ar e o f doub t f u l q ua l i t y t he cans s houl d a l s o be l eak t est ed ( s ee " L eakt e st s " , p. 52) .

Gl as s cont a i n er s . Sampl es of gl a s s cont a i n er s s houl d be exam ned f or de f ec t si n c o ns t r uc t i o n a nd f or v ar i a t i o ns i n di me ns i o ns t hat may a f f e c t t hei rabi l i t y t o be pr ope r l y c l o s ed and t o wi t h s t and i mp ac t s and ot he r ab us es whi char e enc ount er e d dur i ng f i l l i ng, c l os i ng, p r o c es s i ng, d i s t r i but i on ands t or a ge . Qua l i t y c ont r o l s t a f f s houl d gi v e s pe ci a l at t e nt i o n t o t h e s ea l i ngs u r f a c e of gl a s s c o nt a i ne r s ; t hi s s ur f a c e s ho ul d be ho r i z o nt a l and s mo ot hand i t shoul d make a c l ean l y - def i ned and con t i nuous cont act wi t h t he gasketwh en t he c l o s ur e i s appl i ed und er u s ua l p r oces s i n g con di t i ons .

Ma ny t y pes of c l o s ur e s a r e a ppl i e d t o gl a s s c o nt a i ne r s s o qua l i t yc o nt r o l s t a f f s ho ul d o bt a i n i nf o r ma t i o n o n t he s t r uc t ur e and a ppl i c a t i o n oft h e c l o s ur e s f r o m t h e c o nt ai ner ma nuf a ct ur e r t o pl a n r e al i s t i c i ns pec t i onpr o ce dur e s . T he c r i t i c al f ac t o r s i nf l uenc i ng t h e qua l i t y of t h e s eal ong l as s con t a i n er s i nc l ude t he d i mens i ons of t he c l o s ur e and t h e t y pe , quant i t yand di s t r i but i o n of t he ga s ke t ma t e r i a l . T he s t o r a ge pe r f o r ma nc e of gl a s scont a i n er s c l o s ed wi t h met a l c l o s ur es o f t en d ep en ds on t he r es i s t ance of t hec l o s ur e t o c o r r o s i o n by t he pr o duc t , e s pe c i a l l y an a c i di c pr oduc t c o nt a i ni ngs al t and s ul phur di o xi de . Me t a l c l o s ur e s a r e us u al l y p r o t e ct e d by ani nt e r n al l a cque r whi c h mus t h av e e xc e l l e nt ba r r i e r pr o pe r t i e s . Sa mpl ec l o s ur es s houl d t he r e f o r e be exam ned t o de t e r m n e t hat t he l acquer i se s s ent i a l l y c o nt i nuo us , a ppl i e d at t he s pe c i f i e d c o at i ng ma s s ( s ee " L a c que rcoat i ng mas s " , p . 5 1) and adh er es s t r ong l y t o t he s u r f ace o f t he met a l ( s ee" L a c que r a dhe s i o n" , p. 51) .Pl as t i c pouc hes and s em - r i gi d al um ni um t r ay pac ks . Sem - r i gi d al um ni umt r ay packs have some t echn i ca l f eatu r es i n common wi t h p l as t i c pouches i nt hat t hey a r e c l o se d by hea t s e al i ng and t hey ha ve s o me f l e xi bi l i t y . Qua l i t y


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c ont r ol s t a f f s houl d c onf i r m t he i dent i t y and t hi c knes s of pl as t i c pac kagi ngma t e r i a l s s i nc e t hes e pr o pe r t i e s ma i nl y de t e r m ne t h e ba r r i e r pr o pe r t i e s oft h e pa ck age ( Br i t i s h Ce l l o pha ne , 1970) . I f t he s he l f l i f e of t he pr o duc t i sc r i t i c a l l y de pe nde nt o n t he ba r r i e r pr o pe r t i e s of t he p ac k a ge , t he o xy ge npe r me abi l i t y a nd/ o r t he wa t e r v apo ur pe r me abi l i t y and t he i nt e gr i t y of s a mpl ep ackages s h oul d be de t e r m n ed b ef o r e t hey a r e us ed i n p r od uc t i on ( s ee " L eakt es t s " , p. 52; " Ox ygen pe r me abi l i t y " , p. 53; " P i nhol e t es t f or pac k agi ngf i l ms " , p. 55; " Wat er v apo ur t r ans m s s i on r a t e " , p. 59) .L abe l s , c ar t o ns and ot her ul t i ma t e c ont a i ner s . Qual i t y c ont r o l s t a f f s houl di ns pe ct and me as u r e t he se i t e ms t o d e t e r m ne t hat t hey c o nf o r m t o t h epu r c h as i n g s p ec i f i c a t i o ns . T he i nf o r ma t i o n di s pl a ye d o n l a be l s and o nu l t i ma t e c o nt a i ne r s s h oul d be c he ck ed f o r ac c u r a c y , a nd t he r e gi s t r a t i o n andqua l i t y of t he pr i nt i ng and ar t wo r k s ho ul d be a s s es s e d by qua l i t y c o nt r o ls t a f f .

Det er gent s , s ani t i z er s and s i m l ar mat er i al s

Qua l i t y c o nt r o l s t a f f s h oul d i ns pe ct t he se i t e ms o n r e c ei v al us i n g t he s a mea ppr o ac h a s t hat de s c r i be d f or f ood i ngr e di e nt s ( s ee " S uga r , s al t , s p i c e s ,f ood a ci ds and ot her m no r i ngr e di e nt s " , p. 11) .

3. 2 PREPARATI VE TREATMENTSP r o duc t i o n s t a f f ha ve pr i mar y r e s pons i bi l i t y f or c ar r y i ng out s uc h t r ea t ment sa s s o r t i ng , gr a di n g, wa s hi ng , b l a nc hi ng and m x i ng. Ho we ve r , be c aus e qua l i t yc o nt r o l of t he s e o pe r a t i o ns i s ma i nl y bas ed o n v i s u al i ns p ec t i o n pr o duc t i o ns t af f s houl d be e nc our a ged t o a ss i s t qua l i t y c ont r o l s t a f f t o e ns ur e , f ori ns t anc e, t hat :

. s o r t i n g and t r i mm ng i s pr o pe r l y do ne ;

. f o r e i gn ma t e r i a l i s r e mo ve d;

. t he pr oduc t i s t h or oughl y was h ed ;

. t he pr o duc t i s s ub- di v i de d a s r e qui r e d f or t he s t y l e of t he pa c k;

. t he pr o duc t mo ve s c o nt i nuo us l y and wi t h m ni mum de l a y t hr o ugh t hev ar i o us ope r a t i o ns .Qua l i t y c ont r o l s t af f s houl d mo ni t o r t he c o nc ent r a t i o n of c he m c a l s i nc he m c a l pe el i ng bat hs ; us ua l l y t h e a ct i v e ma t e r i a l i s c aus t i c s o da ( s odi um

h y dr ox i d e ) s o ac i d t i t r a t i ons s houl d be done o f t en enoug h t o ens u r e t h at t her e qui r e d c o nc e nt r a t i o n c an be ma i nt a i ne d ( s ee " Ca us t i c s o da ( l y e) " , p. 23) .

Qua l i t y c o nt r o l s t a f f s ho ul d a l s o c he ck t he c o mp os i t i o n of br i ne s andsyr ups used as pack i ng medi a and i n t he manuf act u r e o f p i ck l ed , s y r uped andc r y s t a l l i z e d pr o duc t s . T he c o nc e nt r a t i o n of s al t i n s i mpl e br i ne s ma y bees t i mat ed by h yd r omet r y ( s ee " S a l t " , p . 27 ) , and i ndi ca t ed by a s i mp l e t es t o fel e ct r i c al c onduc t i v i t y , or even by t as t i ng. I n b r i nes c ont a i ni ng ot hersubs t ances chem ca l met hods ar e used t o de t e r m ne t h e c o nc e nt r a t i o n of s al t( s ee " Sal t " , p. 27) .T he c o nc e nt r a t i o n of s u ga r i n s i mpl e s y r ups i s mo st r e adi l y de t e r m ne d


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by r e f r ac t omet r y but hydr omet r y may a l so be used ( see " Sol ubl e so l i ds ,s u ga r " , p. 28) . Aga i n t a s t i ng gi v es an e s t i ma t e of t he s t r e ngt h of a s y r u p.Br i nes and sy r ups a r e somet i mes ac i d i f i ed and i n some i ns t ances t hel evel of ac i di f i c at i on i s c r i t i c al l y i mpor t ant i n det er m ni ng t he s af et y oft h e f i nal pr oduc t . Qual i t y c ont r ol s t a f f s houl d c hec k t he ac i di t y of eac h

bat c h of ac i di f i ed br i ne or s yr up by al k al i ne t i t r at i on ( s ee " Ac i di t y" ,p. 20) ; pH me as u r e me nt s or t as t i ng a r e not a ppr o pr i a t e i n t hi s s i t ua t i o n.

3. 3 FI L L I NGQual i t y c ont r ol st af f s houl d moni t or t h e f i l l i ng o per at i on t o ens ur e t h ateach cont a i ner r ecei ves a t l eas t t he nom nat ed amount o f t he p roduc t and t hatt h e c ont ai ner i s not exc es s i vel y f i l l ed. Ex ces s i v e f i l l s ar e c ommer c i al l ywast ef u l and i n some i nst ances t hey may be hazar dous. For exampl e , t hedoubl e seams of canned f oods may be damaged i f t he can i s over f i l l ed becauset he pr oduct expands mor e t han t he met a l o f t he can dur i ng t he heats t e r i l i z a t i o n pr o ce s s . T he f i l l may be c hec k ed by we i g hi n g or by me as u r i n gt he vo l ume o f t he p roduc t . The headspace , i . e . t he d i s t ance bet ween t he t opof t he open can and t he sur f ace o f t he pr oduct , may a l so be measur ed ( see" Headspace o f canned f oods" , p . 50) . I t shoul d be r emember ed t hat t he massand v ol u me of a pr oduc t wi l l var y wi t h i t s de ns i t y , and de ns i t y wi l l v ar ya c c or d i n g t o t he c o mp os i t i o n of t he pr o duc t and i t s t e mp er a t u re .

Qual i t y c ont r o l s t a f f , wi t h s uppor t f r om pr o duc t i on s t af f , s houl di ns pec t t h e f i l l i ng oper a t i on t o ens ur e t hat t he s e al i ng s ur f ac es of t hec o nt a i n er s ar e not c o nt a m n at e d wi t h s p i l t p ro d uc t s wh i c h ma y c a us e t he s e alt o be s u bs t a nd ar d . F i b ro u s v eg et a bl e t i s s u e ma y c a us e l e ak y s e al s i f t het i ssue i s i ncor por a t ed i n doubl e seams of cans o r bet ween t he gasket andf i ni s h of gl as s c ont ai ner s . The hea t - s e al s u r f ac es of f l ex i bl e pouc hes ands em - r i gi d al um ni um t r ay pac ks s houl d al s o be f r e e of t he pr o duc t andmo i s t u r e i f sound heat sea l s a re t o be p r oduced .

I n s ome pr oc es s e s , e. g. t h e hot - f i l l , c l os e , hol d and c ool pr o cedur ewhi c h i s s o me t i me s us ed i n c anni ng ac i d f o ods , t he t e mp er a t u r e of f i l l i ng i sa c r i t i c al f ac t o r i n ens ur i ng t h e pr oduc t i s s hel f - s t abl e . T hi s t e mper at ur es h ou l d be mo ni t o re d c o nt i n ua l l y us i n g a t e mp er a t u re r e c or d er , or i t s h oul d beund er f r e que nt o bs e r v at i o n of qua l i t y c o nt r o l s t a f f wi t h t he s u ppo r t ofpr o du ct i o n s t a f f . T he t e mpe r a t ur e of f i l l i ng ma y a l s o be an i mpor t a nt f ac t o ri n p r o du ci ng t h e r equi r ed v ac uum i n c anned p r o duc t s and a ga i n t hi st emper at ur e shoul d be moni t or ed as descr i bed above.

3. 4 CLOSI NG AND SEALI NG OPERATI ONSMa ny p ro c e s s ed f r ui t and v eg et a bl e p ro d uc t s mus t be h er me t i c a l l y s e al e d i nt hei r pr i ma r y pa ck age i f t hey a r e t o be s a f e and s h el f - s t a bl e . Qual i t yc ont r ol s t a f f , pr e f e r abl y wi t h as s i s t a nc e f r om pr o duc t i on s t af f , s houl di ns pec t f i l l ed c ont a i ne r s , l oo s e e nds and c aps as t h ey a r r i v e at t he c l os i ngma c hi n es o r h ea t - s e a l e r s , and s ome of t he c l o s ed c o nt a i n er s a s t hey l e av e t h ec l os i ng ope r a t i on.

Op er a t o r s of c an c l o s er s s h oul d i ns p ec t t he f i ni s h ed d ou bl e s e ams f ord ef e c t s s u c h a s dr o op s , s p ur s , c u t - o ve r s a nd f a l s e s e ams . At r e gul a ri n t e r v al s , d ep en di n g on t he r a t e of pr o duc t i o n, d et a i l e d e xa m na t i o ns s houl dbe ma de of t he c l o s ur e s o n s a mp l e c o nt a i n er s t a ke n f r om e ac h he ad o f t hec l o s i n g ma c hi n es . S amp l e s s h ou l d a l s o be e xa m n ed a f t e r t he ma c hi n e i s


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adj u s t ed and a f t e r acc i d en t s t hat may h ave a l t e r ed t he s e t t i n gs o f t hec l o s i ng machi n es and t he qua l i t y of t he s eal s ( s ee " Doubl e s eams " , p. 33) .The ass ess ment of heat seal s shou l d be mai n l y based on v i sualex am n at i ons d ur i n g p r od uc t i on but t he s eal s s h oul d be p r es s u r e t es t ed wh ent he s e al i ng ma c hi ne s a r e be i ng a dj us t e d be f o r e pr o c es s i ng s t a r t s o r a f t e ra c c i de nt s t hat may a l t e r t hei r p er f o r ma nc e ( " L e ak t e s t s " , p. 52) .Qua l i t y c o nt r o l s t a f f s h oul d a l s o c he ck t hat t he c or r e ct d at e , pr o duc tna me and ma nuf a c t ur e r ' s c ode s a r e be i ng a ppl i e d i n l e gi bl e f or m t o t hep r i mar y cont a i n er s , and t hat t he app r op r i a t e codes a r e changed f r equent l ye no ugh t o a l l o w pr o duc t i o n ba t c h e s t o be i de nt i f i e d and i s o l a t e d i f t he r e i sev i d en ce t hat t hey a r e d ef ec t i v e .

3. 5 PRESERVATI ON TREATMENTSI n a ddi t i o n t o pa c ka gi ng pr o ce s s ed f r ui t s and v ege t a b l e s i n pr o pe r l y s eal edcont a i n er s , t he p r od uc t s mus t b e g i v en o t h er t r eat ment s t o ens u r e t hat t heya r e s t abl e d ur i n g s t o r ag e. Some pr es e r v a t i on t r eat ment s s u ch as d eh yd r a t i onand c r y s t a l l i z i ng a r e us ua l l y do ne be f o r e pa c ka gi ng wh i l e o t h er t r e at me nt sa r e us ua l l y appl i ed af t er pac k agi ng, e . g. t he heat s t e r i l i z a t i o n pr o ce ss i nc a nni ng. T he pr e s er v at i o n t r e at me nt s i nv ol v e di f f e r e nt p hy s i c a l a nd c he m c a lpr o c es s e s and t h ey r e qui r e di f f er e nt a ct i o ns by qua l i t y c ont r o l s t af f t oens u r e t h at s a f e , s t abl e p r oduc t s ar e pr oduced.

Canned FoodsThe sa f et y and s t o r a ge s t a bi l i t y of c anned f o ods , i nc l udi ng he at - pr o c es s e df oods i n dr ums , gl a s s c ont a i ne r s , f l ex i bl e and s em - r i gi d c o nt a i ne r s , dependon t he pr oduc t be i ng heat ed at a s p ec i f i ed t emper a t ur e f or a s p ec i f i ed t i me .The most commonl y used heat i ng medi a ar e hot wat er , somet i mes under as upe r i mpo s ed p r e s s u r e , and a i r - f r e e s a t u r a t e d s t e am

Qua l i t y c o nt r o l s t a f f s ho ul d e ns u r e t h at t he pr i ma r y c o nt r o li ns t r ume nt s f or he at - s t e r i l i z a t i o n pr o ce s s es , t he t her mo me t e r and c l o c k, a r eaccu r a t e and ma i n t a i ned i n good condi t i on. Mer cu r y - i n - g l as s t h er momet e r s , o rt emperat u r e- measur i ng i ns t r ument s o f at l eas t t he same accur acy andr e l i a bi l i t y , s houl d be c al i br at ed at l eas t t wi c e a y ea r or mo r e f r e quent l y i ft hei r s e t t i ng s a ppe ar t o ha ve be en di s t ur be d ( s ee " C al i br a t i o n oft he r momet e r s f o r pr oces s i n g equ i p ment " , p. 30 ) .Mo s t he at - s t e r i l i z i ng equi pme nt s ho ul d al s o be f i t t e d wi t h c ha r t

r eco r d e r s wh i ch g i v e a pe r manent g r ap hi ca l r ecor d o f t he t emp er a t u r e of t hehe at i ng me di um a nd, wi t h b at c h pr o c es s e s , a r e cor d of t he d ur a t i o n o fh ea t i n g. Thi s r ecor d s houl d be us ed by q ua l i t y cont r o l s t a f f at t he end ofeach s h i f t t o ch eck t hat t he s p ec i f i ed p r oces s es wer e appl i ed and t o conf i r mt he p r oces s i n g d et a i l s r ecor ded i n t he l og book ma i n t a i n ed by t he ope r a t o r so f t he h ea t - p r oces s i n g s y s t ems .At r e gul ar i nt e r v al s , pe r haps we ek l y , qual i t y c ont r o l s t af f s houl di ns pec t t he he at - s t e r i l i z i ng e qui pment t o e ns ur e t h at i t i s o pe r a t i ng i n t her equi r ed way . Sp ec i a l a t t ent i on s houl d b e g i v en t o t he v a l v es on t hecomp r es s ed a i r and wa t e r l i nes t hat a r e conn ec t ed t o s t eam- h ea t ed s t e r i l i z i n gequ i p ment . The t r aps on s t eam- heat ed r e t o r t s s houl d a l s o be i n s pec t ed t oe ns u r e t h at c o nde ns a t e i s qui c k l y r e mov ed f r om r e t o r t s . T he s t e am wa t e r a nd

a i r d i s t r i bu t i o n pi pe s s houl d be i ns pec t e d f or b l o c ka ge s a nd r us t de po s i t s


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and t he sys t ems used t o c i r cu l a t e wat er i n wat er - heat ed equ i pment s houl d bec he ck ed t o de t e r m ne t hat t he e qui pme nt i s o pe r a t i ng s a t i s f a c t o r i l y ( Codex2- 1969; Codex 23- 1979) .

Dehydr at ed FoodsThe s a f e t y and s t o r ag e s t abi l i t y of d eh ydr a t ed f ood s , i nc l ud i n g s ome s y r u pedand c r y s t a l l i z ed f oods , d epend on t he mo i s t u r e cont ent o f t he pr oduc t be i ngr educed t o a va l ue at wh i ch pot ent i a l spo i l age or gan i sms cannot gr ow ( Codex3- 1969; Codex 5- 1971) . Al t hough equi l i br i um r e l at i v e hum di t y ( " Equi l i br i umr e l a t i v e hum di t y " , p. 46. ) i s t he bes t i ndex of t h e amount of wa t e r av ai l abl ef or m c r o bi a l gr owt h, qual i t y c ont r o l of dehy dr a t i on pr oc es s es i s us ual l ybased on t he measur ement o f mo i s t u r e cont ent ( " Mo i s t u re" , p . 24) . Ther el at i ons hi p bet ween moi s t ur e c ont ent and equi l i br i um r e l at i v e hum di t yv a r i es acco r d i n g t o t he comp os i t i on of t he f ood s o t he mo i s t u r e cont entr equi r ed t o g i v e a s h el f - s t abl e pr oduc t s houl d be d et e r m n ed f or each f ood.

Su l phu r d i ox i d e i s added t o s ome f oods b ef o r e , du r i n g or a f t e r t hedr y i ng pr o c es s , s o me t i me s as an a nt i - m c r o bi a l a ge nt , but mo r e o f t e n t o bl o ckno n- e nz y m c br o wni ng of t he pr o duc t dur i ng s t o r a ge . Qua l i t y c o nt r o l s t a f fs houl d t he r e f o r e moni t o r t he s u l p hu r i n g p r oces s es and t he concent r a t i on ofs u l p hu r d i oxi de i n t he f i ni s hed pr oduc t t o ens u r e t hat enough i s pr es entt o meet t he t echnol ogi ca l needs but t he amount does not exceed t he l i m t s setby r egul at or y a ut ho r i t i e s ( " Sul phur d i ox i de" , p. 30) .

F r oz en f oodsT he c r i t i c a l f a ct or i n e ns ur i ng t hat f r o z en f o ods a r e s a f e and s t o r es a t i s f a c t o r i l y i s t h e t e mpe r a t ur e of s t o r a ge whi c h s ho ul d be ma i nt a i ne d at anes s ent i a l l y cons t ant v a l u e at or be l ow - 18C (Codex 8 - 1 97 6) .

Qu al i t y cont r o l s t a f f s houl d meas u r e t he t emp er a t ur e o f t he pr oduc t( s ee " T e mpe r a t ur e of f r oz e n f o ods " , p . 5 7) as i t l e av es t he pr o duc t i o n l i ne t oens u r e t hat f r eez i n g i s compl e t e and t o d et e r m n e wh et h er t he p r oduc t s houl dbe c l o s e - o r open- s t acked i n t he col d s t o r ag e r oom The t emp er a t ur e of t hec ol d s t o r a ge r o om s ho ul d be mo ni t o r e d at l e as t t wi c e da i l y or pr e f e r a bl y byus i ng a c har t r e c or de r . Qual i t y c ont r o l st a f f s houl d al s o i ns pec t t h e c ol ds t o r a ge s pa c e t o de t e r m ne t h at i t i s c l e an and t hat s t o c k i s pr o pe r l yhandl ed and r o t at ed.

P i c k l e d a nd c he m c a l l y pr e s er v ed f o odsSp oi l age of t hes e f oods i s pr event ed by es t abl i s h i n g a d e f i ned chem ca lenv i r onment t hr oughout t he p roduct and by p r ocess i ng t he r aw mat er i a l s sot hat t he pr oduc t i s cont am nat ed onl y by l ow n umb er s of m c r o - o r g an i s ms . Themat e r i a l s us ed t o make t hes e pr odu c t s s h el f - s t abl e i n c l ud e s ome of t hos ede s c r i be d i n s e c t i o n 4. 2: a c et i c and o t h er f ood a c i ds ( p. 20) ; be nz o i c ac i d( p. 22) ; s al t ( p. 27) ; s ugar ( p. 28) ; s or bi c ac i d and s o r ba t e s ( p. 29) ; andsu l phur d i ox i de ( p . 30 ) . I n many cases t he pH o f t he f ood mus t a l so bec ont r ol l ed t o o bt ai n s he l f - s t a bl e pr o duc t s ( s ee " p H" , p. 25) .

Qua l i t y c o nt r o l s t a f f s houl d e ns ur e t hat t he ma nuf a c t ur i n g pr o ce s s i sc ar r i ed out s o t hat t he l evel of m c r o bi al c ont am nat i on i s m ni m z ed.Qua l i t y c o nt r o l s t a f f s ho ul d al s o mo ni t o r t he pH and t he c o nc e nt r a t i o n of t h ec r i t i ca l p r es e r v i n g agent s i n each pr oduc t ba t ch o f t en enoug h t o ens u r e t hat


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t h e end pr o duc t wi l l c ompl y wi t h i t s s pe ci f i c at i o ns . Us ua l l y s a mpl e s f oranal y s i s s houl d be t aken f r o m di f f er ent p ar t s of pi c kl i ng or s yr upi ng t a nkst o de t e r m ne t hat t h e c r i t i c al ma t e r i a l s ar e pr o pe r l y di s t r i but e d and pr es entat c onc ent r a t i ons wi t hi n t he l i m t s set f or t he pr oc es s .

3. 6 LABELLING, PACKAGING AND WAREHOUSINGQua l i t y c o nt r o l of t hes e o pe r a t i o ns i nv ol v es i ns pe ct i o n of t he l a be l l i ng andpa c ki n g pr o c es s t o de t e r m n e t hat t he c or r e ct ma t e r i a l s ar e be i ng u s ed , t hatt he p r od uc t s a r e b ei n g p r op er l y packed and t he u l t i ma t e cont a i n er s a r es ec ur e l y s t ac k ed r eady f or d i s t r i but i o n.

Qua l i t y c o nt r o l s t a f f s h oul d i ns pe ct wa r e h ou s e s t o c ks at a ppr o xi ma t e l ywe ek l y i nt e r v al s f o r e vi de nc e of s po i l a ge and ot her f or ms of de t e r i o r a t i o n,and t o e ns u r e t h e wa r e ho us e i s c l e an, o r de r l y and f r e e o f f o r e i gn ma t e r i a l sand i nf e s t a t i o n.A s h or t t i me be f o r e s t o r ed s t ocks a r e t o be s h i p ped qu al i t y cont r o ls t a f f s houl d s e l ec t one ul t i mat e c ont ai ner f r o m f i ve wi del y di s t r i but edp oi n t s i n each ba t ch i n t he cons i g nment . Each p r i mar y cont a i n er i n t hes es amp l es s h oul d be i ns p ec t ed f o r ev i d en ce of s p o i l age and o t he r f o r ms ofde t e r i o r a t i o n. One pr i mar y c ont a i ne r f r om e ac h ul t i ma t e c ont a i ne r s houl dt hen be t a ke n f or mo r e de t a i l e d e xa m n at i o ns . T he pr o duc t f r o m e ac h pr i ma r yc o nt a i n er s ho ul d be t as t ed t o de t e r m ne t hat i t h as a c c ep t a b l e o r g a no l e pt i cpr oper t i es .Ca ns s ho ul d be e xa m ne d f or v ac u um e xc e s s i v e i nt e r n al c o r r o s i o n,s t a i ni ng and l o ss of a dhe s i o n by t he l a c que r ( s ee " l a c que r a dh es i o n" , p. 51," v a c uum" , p. 58) . I f t he m c r o bi o l o gi c a l s t a bi l i t y of t he pr o duc t de pe nds oni t s pH, e . g. , i n a c i di f i e d l o w- a ci d f o ods , t he pH s ho ul d be me as u r e d ( s ee

" p H" , p. 25) .I f t he i nt ended ma r k et r e qui r e s pa r t i c ul a r c ha r a c t e r i s t i c s i n t hepr o duc t , e . g. , mo r e t han a m ni mum dr ai ned we i ght or s y r up s t r e ngt h,app r opr i a t e meas ur ement s s houl d be made ( s ee " S o l u bl e s o l i d s ( s u ga r ) " , p. 28;" Dr a i ned mas s " , p. 32) .Dr i e d f o ods s houl d be i ns pe ct e d f or i nt e gr i t y of t he pa c k ag e, i ns ec ti nf e s t a t i o n and m c r o bi a l s po i l a ge , e s pe ci a l l y by mo ul ds . T he mo i s t ur ec o nt e nt a nd , wh en a ppr o pr i a t e , t he c o nc e nt r a t i o n of s u l phur d i o x i d e o r o t h erma t e r i a l s s p ec i f i e d by t he pur c ha s i ng and r e gul a t o r y a ut h or i t i e s s ho ul d bede t e r m ne d ( s e e " Mo i s t ur e " , p. 24; " S ul phur d i o xi de " , p. 30) .W t h f r o ze n f o ods t he f i nal e xa m na t i o n us ua l l y i nv ol v es i ns pe ct i o n oft he pr i mar y p ackage and o r g an ol ept i c t es t i ng of t he p r od uc t . The t emp er a t u r eo f t he pr o duc t s ho ul d a l s o be me as ur e d t o c o nf i r m t hat i t i s at o r be l o w t her ecommended va l ue (s ee " Temper at u re o f f r ozen f oods" , p . 57) .The concent r a t i on o f s a l t , a c i d and p r es e r v a t i v es and t h e pH s h oul d bed et e r m n ed as app r op r i a t e i n pi ck l ed and p r es e r v ed p r od uc t s b ef o r e t hey a r edi s pa t c h ed ( s ee " Ac i di t y " , p. 20; " Be nz oi c a ci d" , p. 22; " p H" , p. 25; " S al t " ,p. 27 ; " S ol ubl e s o l i ds , s uga r " , p. 28; " S or bi c ac i d and s o r b at e s " , p. 29;" S ul phur di o xi de " , p. 30) . At t e nt i o n s houl d be gi v en t o t he c ondi t i o n ofme t a l c o nt a i n er s and t o t he me t a l c l o s ur e s o n gl a s s j a r s e s pe c i a l l y as t hes epr o duc t s ar e of t en par t i c ul ar l y c o r r os i v e.


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3. 7 CLEANI NG, SANI TATI ON AND WASTE DI SPOSALQua l i t y c ont r o l s t a f f shoul d mo ni t o r a l l o pe r a t i o ns t h at c ont r i but e t o t h ema nuf a c t ur i ng pr o c es s be i ng c ar r i e d out unde r s a t i s f a c t o r y hy gi e ni ccond i t i ons . The f ood p r oces s i n g equ i p ment t h at h an dl es t he pr odu c t dur i n gand a f t e r t he l as t s t eps o f t he p r ep ar a t i v e ope r a t i ons s houl d be kept atl eas t as c l ean as t he k i t c he ns of a we l l - r un ho t e l . Qua l i t y c ont r o l s t af fs ho ul d i ns pe ct t he pr o c es s i ng l i ne s be f o r e ma nu f a c t ur i n g s t a r t s t o de t e r m net hat t hey a r e c l ean and f r ee of was t e f ood, f o r e i g n mat e r i a l s and i ns ecti nf e s t a t i o n. T he l i ne s s houl d a l s o be i ns pe ct e d a f t e r t hey a r e c l ea ne d att he end of t h e s hi f t . Dur i ng pr oduc t i o n qua l i t y co nt r o l s t af f s houl d i ns pec tt he l i ne f o r ev i d en ce of accumul a t ed di r t and was t e mat e r i a l , and f or anypr oduc t wh i ch h as been de l ayed o r by - pas s ed on t he l i ne . S pec i a l a t t ent i ons houl d be gi v en t o c anne d f o ods i mme di a t e l y a f t e r t he he at s t e r i l i z a t i o np r oces s ; t he out s i de s u r f ace of t he cont a i n er s mus t be kept as f r ee ofm c r o bi a l c ont a m na t i o n as po s si bl e r e duc e t h e r i s k of o r g ani s ms ga i ni ngent r y t o t he p roduct t h rough t he wet c l osu res wh i ch a t t hat s t age may nothave f o rmed an her met i c sea l . Wet con t a i ner s shoul d not be manual l y hand l edor con t am n at ed by cont ac t wi t h we t and di r t y mech an i ca l equ i p ment . Qua l i t yc o nt r o l s t a f f s ho ul d r e qui r e c an ha ndl i ng e qui pme nt t o be dr y , or i f i t mus tbe wet i t s houl d be r egul ar l y s ani t i z ed. Ther e i s l i t t l e v al ue i n t a ki ngm c r o bi o l o gi c a l s wa bs of f r ui t and v ege t a b l e pr o c es s i ng e qui pme nt t o a s s es st he ef f ec t i v enes s of c l eani ng oper at i ons ; i t i s us ual l y suf f i c i ent t o i ns pec tt h e e qui pme nt , t o s ear c h f or o f f - o do ur s , t o f eel me t a l s ur f a ce s f or s l i m nes sand t o wi pe t he s u r f a c es wi t h a c l e an t i s s ue t o de t e c t r e s i dua l di r t ( Codex 1- 1979) .

Qual i t y c ont r ol s t af f s houl d a l s o i ns pec t al l o t h er a r e as of t hep r oces s i n g pl ant and t he i mmedi a t e out s i d e a r eas f o r ev i d en ce of was t e ,i n s ec t s , r odent s and o t he r ani ma l s , bi r ds and o t he r mat e r i a l s t hat maypr es en t a r i s k t o t he p r od uc t i on o f s a f e , wh ol es ome pr oces s ed f r ui t andv ege t abl e p r od uc t s .


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Chapt er 4

METHODS OF ANALYSIS AND PHYSICAL TESTING

4.1 SCOPET hi s c ha pt e r gi v es de t a i l s of s e l e c t e d me t h o ds of a na l y s i s and phy s i c a l t es t st hat a r e s ui t a bl e f or us e i n t he f r ui t and v ege t a b l e pr o c es s i ng i ndus t r i e s .The met h od s a r e t aken f r om or a r e bas ed on, t hos e d es c r i b ed by d i f f e r en ta ut ho r i t i e s and a ut ho r s . T he y we r e s e l e ct e d be c aus e t hey a r e e f f e c t i v e,s uf f i c i e nt l y a cc ur a t e f or qua l i t y c o nt r o l pur pos e s and i n ge ne r a l t h eyr e qui r e d e qui pme nt t hat s houl d be r e adi l y a va i l a bl e t o t h e f r ui t andv ege t a bl e pr o c es s i ng i ndus t r y .

I t i s poss i b l e t hat a l t er nat i ve met hods may have to be used t o comp l ywi t h t he r e qui r e me nt s of r e gul a t o r y a ut ho r i t i e s or t he pur c ha s er of t hepr o duc t . I t i s al s o pos s i bl e t h at a na l y s es and t es t s i n a ddi t i o n t o t hos edescr i bed may be r equ i r ed.The met h od s des c r i b ed a r e pr es en t ed i n a l p habe t i ca l o r d e r i n t hi sch ap t e r i n S ec t i ons 4 . 2 and 4. 3. . Th e met h od s a r e i nt end ed f o r us e bya ppr o pr i a t e l y t r a i ned t ec hni c al per s onne l s o onl y i n i ns t a nc es i nv ol v i ngs p ec i a l ha z ar d s ar e wa r n i ng s abo ut s a f e t y i nc l ude d.

4. 2 CHEMICAL ANALYSESAcidityT he c onc e nt r a t i o n of f ood a ci ds s uc h as a ce t i c , c i t r i c , l a ct i c and mal i ca c i ds i s e s t i ma t e d by t i t r a t i ng a s a mpl e of t he f ood wi t h s o di um hy dr o xi de t oan end - po i n t a t pH 8 . 1 .P r ocedu r e : F or l i qui d s amp l es t ake 10 m and d i l u t e t o about 10 0 m wi t hd i s t i l l ed wa t e r . F or s ol i d s amp l es t ake 10 g and bl end wi t h about 5 0 m o fdi s t i l l ed wat er t o a uni f or m di s per s i on, t r ans f e r t o a c oni c al f l as k wi t hwat er .

Add 0. 3 m of i ndi c at or ( . 1% phe no l pht ha l e i n i n 95% e t ha no l ) a ndt r i t r a t e wi t h 0. 1 N s o di um hy dr o xi de t o a pe r ma ne nt pi nk c o l o ur .I f t he co l our o f t he s ampl e obs cu r es t he co l our ch an ge o f t he i n di ca t o rt he end - p oi n t o f t he t i t r a t i on (p h 8 . 1 ) s houl d be de t e r m n ed us i n g a pH met e r( s ee " p H" , p . 25) . An a l t e r n at i v e pr o c edur e i s t o us e a n e xt e r n a l i ndi c a t o r( 1% phe no l pht ha l e i n i n po wde r e d po t a s s i um s ul pha t e on a s pot t i l e ) .

Res ul t s : T i t r a t a bl e a c i di t y i s us ua l l y r e po r t ed as p er c e nt a ge ma s s / v ol umef or l i qui d p r o duc t s and pe r c e nt age, ma s s / ma s s f or s ol i d a nd s e m - s o l i dpr o duc t s . T he r e s ul t s mus t a l s o na me t he a ci d s e l e ct e d f or c a l c u l a t i n g t he


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t r i t r at abl e ac i di t y, t hi s ac i d us ual l y bei ng t h e pr edom nant ac i d i n t hepr oduc t , e. g. , c i t r i c ac i d i n c i t r us pr oduc t s , ac et i c ac i d i n pi c kl es andma l i c ac i d i n po me f r ui t s .F or 10 m or 10 g s a mpl e s of pr o duc t , t he pe r c e nt a ge t i t r a t a bl e a ci di t yi s c al c ul a t e d us i ng t he e qu at i o n.Tr i t r a t a bl e ac i di t y ( %) = number of m of 0. 1 N s o di um hy dr o xi demul t i pl i e d by a c o nv er s i o n f ac t o r .

wh er e t h e c o nv er s i o n f a c t o r i s :Ac et i c ac i d 0 . 060Ci t r i c ac i d ( a nhy dr o us ) 0. 064Ci t r i c ac i d ( hydr ous ) 0 . 070L ac t i c ac i d 0 . 090Mal i c ac i d 0 . 067Tar t ar i c ac i d 0 . 075

Af l a t o xi n s r a pi d s c r e eni ng me t h odAf l a t o x i n s ar e e xt r a c t e d f r om t he s a mp l e by b l e nd i n g at h i g h s p ee d i n a qu eo usac et one , p ur i f y i ng wi t h ammoni um s ul phat e, r e - e x t r a ct i ng i nt o benz ene ,e va po r a t i n g t o d r y ne s s , and r e di s s o l v i ng i n c hl o r o f o r m- a c et o ne . T he f i nals o l u t i o n i s s u bj e c t e d t o d es c e n di n g m n i c o l u mn c h ro ma t o gr a ph y t hr o ughs uc c es s i ve l ayer s of a l um na, s i l i c a gel and Fl or i s i l , and t he af l at oxi n bandi s v i s ual i z ed by f l uor es c enc e.P r ocedur e : P r epar a t i on o f co l umn. P l ug one end o f a g l ass t ube ( 3 mmi nt er nal di a x 23 c m l o ng) wi t h 5 mm of gl a s s wo ol . Add i n t he f ol l owi ngor der : 5 - 7 mm f i ne gr a nul a r s and, 5 - 7 mm F l or i s i l ( 200- 300 mes h, dr i ed 2 hat 110 C) , 19- 20 mm s i l i c a g el ( dr i e d 2 h at 110 C) . T ap t h e t ube a f t e r e ac haddi t i on t o f o r m f i r m l ayer s .P r e pa r a t i o n of s a mp l e . Bl e nd 50 g p or t i o n of dr y s a mp l e wi t h 10 g Ce l i t ef i l t e r ai d and 150 m a c et o ne wa t e r ( 85 + 15) f or 3 m n at h i g h s p ee d.F i l t er by gr av i t y t hr ough 18. 5 cm open- t ex t u r e f i l t er paper a nd c ol l ec t 60- 70m f i l t r at e.T r a ns f e r 50 m f i l t r a t e t o 250 m be ak er , add 20 m 40% a qu eo us a mmo ni u ms u l ph at e and 130 m d i s t i l l e d wa t e r , s t i r , and l et s t and 2 - 3 m n. Add about10 g Cel i t e , s t i r , and f i l t er t hr ough 1 8. 5 cm pape r . T r a ns f er 100 mf i l t r at e t o 125 m s e par at or y f unnel wi t h T ef l on s t o pc oc k . F r o m pi pet t e, a dd3 . 0 m b en zen e; s t o pp er f unne l and s h ak e v i g or o us l y 60 s e c . Af t e r ph as es e par at i on, dr ai n and di s c ar d l ower ( a queo us ) l ay er . Add 50 m di s t i l l edwa t e r t o b en zen e i n s e pa ra t o ry f u nne l a nd wa s h by s wi r l i n g ( v er y g en t l y , t oa vo i d e mu l s i o n f o rma t i o n) ; a ga i n d ra i n and d i s c a r d a qu eo us l a ye r . T r a ns f e rb en zen e e xt r a c t t o v i a l and e va po r a t e j us t t o d r y ne s s i mme rs i o n i n ho t wa t e runder a s t r eam of dr y ni t r ogen. Redi s s ol v e r es i due i n 3. 0 mc hl o r o f or m- ac et one ( 9 + 1) . P r e par e bl ank i n i dent i c al way f r o m mat e r i al swhi c h i s k no wn t o be af l a t o x i n- f r e e.Chr o ma t o gr a phi c anal y s i s . Us i ng s y r i nge, t r ans f er 1. 0 m al i quot s of bl anka nd s amp l e s on t o s e r i e s of c o l u mn s wh i c h a re s up po r t e d i n v er t i c a l p os i t i o n,and l et e ac h d ra i n c o mp l e t e l y . T o e ac h c o l u mn , a dd 1. 0 m c h l o r o f o r m- a c et o ne( 9 + 1 ) and a ga i n l et dr a i n . Ob s er v e f l u or e s c e nc e u nd er l o ng - wa veul t r avi ol et i l l um nat i on. Pr es enc e of af l at ox i ns i n s ampl e r es ul t s i n bl ue


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f l uor es c ent band at t o p of F l or i s i l l ayer , c l ear l y di s t i ngui s habl e byc o mp ar i s o n wi t h bl a nk .Wa r n i n g. Af l a t o x i n s a re v er y t ox i c s o r u bb er g l o v es s h oul d be wo r n andma ni p ul a t i o ns s h ou l d be c a r r i e d o ut i n a f ume c u pb oa r d . Gr i n di n g o f dr ysampl es may r esu l t i n a i r bor ne dus t so p r o t ec t i ve masks shoul d be used.S pi l l s o f t o xi n and c o nt a m n at e d g l a s s wa r e and e qu i p me nt s ho ul d be t r e at edwi t h 5% s o di u m h yp oc h l o r i t e s ol ut i o n and t hen t ho r o ug hl y wa s he d wi t h wa t e r .

Al c oho l i ns ol ubl e s ol i dsT he cont e nt of a l c ohol i ns ol ubl e s ol i ds i s det er m ne d by we i ghi ng t he r e s i dueo bt a i ne d by bl e nd i ng a s a mpl e of t he dr a i ned pr o duc t wi t h a l c o ho l , f i l t e r i n g,wash i ng t he res i c fue wi t h mor e a l cohol and dr y i ng.P r ocedur e . Canned veget abl es a r e spr ead on an 8 - mesh sc r een and r i nsed wi t ha v o l u me o f wa t e r e qu al t o t wi c e t he v ol u me of t he o r i g i n al c an . F r o ze nveget ab l es a r e t hawed by i mmer s i on i n about t wi ce t hei r vo l ume o f wat e r ata pp r o x i ma t e l y 40 C. Bo t h t y pe s o f pr o du c t a r e t hen d ra i n ed a nd a ny f o re i g nma t e r i a l i s r e mo ve d by h an d. T he d ra i n ed ve ge t a bl e s ( 400 g ) a re bl e nd ed wi t h2 00 m wa t e r t o a f i ne s l ur r y . A 3 0 g s a mpl e of t he s l ur r y i s r e f l ux ed wi t h200 m 80% e t h anol f or 30 m n and t he m x t u r e i s f i l t er ed unde r va cuum us i nga p re - d r i e d and we i g he d Wh at ma n n o. 1 f i l t e r pa pe r i n a 120 mm d i a me t e rBu c hn er f i l t e r . T he r e s i d ue on t he pa pe r i s wa s he d t hr e e t i me s t he n dr i e df or 2 h r s . i n a n a i r o ve n at 100 C and t he ma s s of t he r e s i d ue i s de t e r m n edby s u bt r a c t i n g t h e we i ght of t he pa pe r f r om t he t o t al ma s s .Re s ul t s T he per c ent a ge of a l c oho l i ns o l ubl e s o l i ds i s o bt ai ned bymu l t i p l y i n g t h e ma s s of dr y r e s i du e by f i v e.

Be nz o i c ac i dBe nz o i c ac i d i s es t i mat ed by t i t r at i on wi t h s odi um hy dr o xi de a f t er t he ac i di s s epar at ed f r om t he s ampl e by ext r a ct i on or s t e am di s t i l l a t i on. Ot hera c i d s t hat ma y be e xt r a ct e d or di s t i l l e d wi t h t he be nz o i c ac i d a r e de s t r o ye dwi t h per manganat e.E xt r a c t i o n. T r a n s f e r a s a mpl e of 100 g t o a 50 0 m vo l u me t r i c f l as k wi t hwat e r . Sol i d sampl es shoul d be macera t ed bef o r e t he sampl e i s t aken .Add 10 m 10% s o di um hy dr ox i de and 120 g s o di um c hl or i de and adj us t t h evo l ume t o about 400 m . Shake t he f l ask f r equent l y f o r an hour and make upt o 50 m , m x and f i l t e r . Pi pet t e 100 m f i l t r a t e i nt o a s epar at or ,n eu t r a l i z e wi t h 3 N hy dr o c hl o r i c a c i d t o l i t mus p ape r a nd add an ot h er 4 m of3 N h yd r o c h l o r i c a c i d.

Ex t r ac t t he benz o i c ac i d wi t h 50 m c hl o r o f o r m by c ar ef ul l y s hak i ng t hes e pa r a t o r t o av oi d f o r ma t i o n of an e mul s i o n. Al l o w t he s e pa r a t o r t o s t andf or 30 m n and r u n of f t he c hl or of or m l ayer and f i l t er i t . P i pet t e 25 mf i l t r a t e i nt o a f l as k and ev apo r a t e t he c hl or of or mI f ot he r ac i ds ar e pr es ent t he c hl or o f o r m s houl d be ex t r ac t e d wi t hs o di u m h yd r o x i d e s o l ut i o n. T he o t h er a c i ds a r e t hen de s t r o ye d by a ddi n g 5%p er ma ng an at e t o t he a l k al i n e s o l u t i o n at 45 C un t i l a pi nk c o l o ur pe r s i s t s .The s ol ut i on i s d ec ol or i z ed wi t h a s o l ut i on of s ul phur di ox i de, di l ut es u l p hu r i c ac i d i s a dded t o d i s s o l v e pr e ci pi t a t e d ma ng an es e d i o xi de and t o


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make the solut ion ac id ic . The solu tion is satu rated with sodiu m chlor ide andthe benzoic acid is extracted four times with 15 ml volumes of diethyl ether.The combined ether extracts are washed twice with a small volume of water andiltered into a smal l fla sk, the filter being wash ed with more eth er. Theether is evap orat ed and the residu e of benz oic acid is disso lved in 2 mlacet one and 2 ml wate r is ad ded . The benzo ic acid is titrate d with 0.05 Nsodiu m hyd rox ide usin g phe nol red solut ion (diss olve 50mg phenol red in 2.85ml 0.05 N sodium hy drox ide and 5 ml 90% ethan ol by war min g and make up to 250ml with 20% ethanol) as the indicator.Re sul ts . The amount of benzo ic acid in the ori gin al sample is ten times thatin the final titr

Quality Control in Fruit and Vegetable Processing

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