COURSE CODE : FST 4822

COURSE NAME : LABORATORY FOR CHEMISTRY AND

TECHNOLOGY OF PLANT AND ANIMAL

EXPERIMENT TITLE : EFFECT OF DIFFERENT HYDROCOLLOIDS ON PINEAPPLE CORDIAL

GROUP NO. : 11

GROUP MEMBERS :

TAN YIH YING 147732

SOON HONN KEONG

FONG PUI KUAN

CHOW SOOK YEE

OON XIAO YI

TAY PEI YIH

148820

149352

148485

149250

148201

HANITA HANIM MOHD ALI

MARDHIAH SUAIDAH BT SHAFIE

HANIS NADIA YAHYA

SITI NORLELA BINTI MOH SALLEH

149217

146573

150897

146106

LECTURER: DR. SEYED HAMED MIRNOSSEINI

Title

Effect of Different Hydrocolloids on Pineapple Cordial

Objectives

1. To investigate the effect of type and concentration of hydrocolloid on the properties of pineapple cordial.

2. To introduce the suitable hydrocolloid for the preparation of pineapple cordial.

Introduction

Fruit cordial is a sparkling clear, sweetened fruit juice, from which all the pulp and other suspended

material are completely removed by clarification (Verma and Joshi, 2000). It contains at least 25 percent juice,

30 percent total soluble solids and 1.5 percent acid (Sethi, Sethi, Deka & Meena, 2005). It is a fruit juice that

needs or needs not to be diluted before it is drunk. Sugar and citric acid are usually added during cordial

processing to increase total soluble solids and also Brix value (Desai, 2000).

In this experiment, pineapple cordial processing was carried out. We learnt the whole processing of

pineapple cordial from cutting, washing, pulping juice extraction to processing and packaging. We were able to

understand the whole process from raw material to the end product. Different groups added different

hydrocolloid into the pineapple cordial to study the effect of different hydrocolloid towards the cordial. The

different hydrocolloids added are carboxymethyl cellulose (CMC), pectin, Arabic gum and unmodified starch.

These hydrocolloids added are to ensure the quality of the cordial. Hydrocolloids are added to the small portion

of cordial before mixing into the whole cordial. This is because the hydrocolloids are difficult to dissolve and

clump together easily. The functions of each step of the processing and also the use of different ingredients

were studied to ensure better sensory characteristics, more stable shelf life and also higher quality of nutritional

values of cordial.

RESULT

Table 1: Weight and Yield of Pineapple

Table 2: °Brix of Juice and Cordial

CMC PectinGum Acacia

PowderUnmodified

starchJuice 9.6 10.3 9.9 10Cordial 45.8 45 42.2 49

Table 3: pH of Juice and Cordial

CMC PectinGum Acacia

PowderUnmodified starch

I II M ± SD I II M ± SD I II M ± SD I II M ± SDJuice extract 3.5

43.54

3.54±0.000

3.54

3.55

3.55±0.0100

3.50

3.53

3.52±0.0224

3.50

3.50

3.50±0.00

Cordial 3.51

3.51

3.51±0.000

3.53

3.54

3.54±0.0100

3.45

3.46

3.46±0.0100

3.59

3.59

3.59±0.00

Table 4: Sensory evaluation on Pineapple Cordial

  

Flavor Aroma Colour Overall Acceptance

G1 G2 G3 G4Averag

e SDG1 G2 G3 G4

Average SD G1 G2 G3

G4 Average SD G1 G2 G3 G4

Average SD

CMC 3 2 2 2 2.25 0.50 2 2 2 2 2.00 0.00 3 2 3 2 2.50 0.58 2 2 2 2 2.00 0.00Pectin 3 3 3 3 3.00 0.00 2 3 3 2 2.50 0.58 3 4 3 3 3.25 0.50 3 3 3 3 3.00 0.00Arabic Gum 5 4 5 5 4.75 0.50 4 4 4 5 4.25 0.50 4 5 4 5 4.50 0.58 4 4 5 5 4.50 0.58Unmodified Starch 3 5 3 4 3.75 0.96 4 5 4 4 4.25 0.50 4 4 5 4 4.25 0.50 4 5 4 4 4.25 0.50

Weight (g) CMC Pectin Gum Acacia Powder Unmodified starchWhole fruit 3390 3481.24 3200 3355Cut fruit 1640 1665.00 1600.28 1725Juice extract 1020 1229.6 1115.91 1070% yield of juice extract (%)

(a) Based on whole fruit 30.8 35.32 34.87 31.89(b) Based on cut fruit 62.19 73.85 69.73 60.03

Table 5: Viscosity and Appearance of Pineapple Cordial

Viscosity (mPas) Shear Rate(1/s) AppearanceWeek 0 1 2 3 0 1 2 3 0 1 2 3

CMC

22.30 25.0020.50

19.90 1550.90 1550.90 1550.90 1550.90

Mix evenly Formation of 2 layers -one orange layer formed on top.

Formation of 2 layers and some bubble appeared

Bubble on surface. 2 layers formed. Dark spot appeared.

Pectin

24.70 20.8031.70

21.10 1550.91 1550.00 1550.90 1000.00

Mix evenly Mix evenly Mix evenly Formation of 2 layers - clear on top- high viscosity at bottom

Arabic Gum

17.40 17.0017.80

11.20 1550.91 1550.90 1550.90 1000.00

Mix evenly Formation of 2 layers - clear on top- high viscosity at

bottom

Mold appear on surface

Much more mold appeared on surface.High viscosity at bottom

Unmodified Starch

23.50 19.9020.10

15.30 1550.90 1550.90 1550.90 999.99

Mix evenly Formation of 2 layers- clear on top- high viscosity at

bottom

Formation of 2 layers

- clear on top - high viscosity at

bottom

Formation of 2 layers- Clear and slightly

moldy on top. - High viscosity at

bottom

Figure 1: Graph of Viscosity versus Storage of Pineapple Cordial

Week 0 Week 1 Week 2 Week 30

5

10

15

20

25

30

35

Viscosity vs Storage Time

CMCPectinArabic GumUnmodified Starch

Storage TIme of Pineapple Cordial (Weekly)

Visc

osity

(mPa

s)

Group 1 Group 2

Group 3 Group 4

Figure 2: Appearance of Pineapple Cordial on Week 0

Group1 Group2 Group3 Group4

Figure 3: Appearance of Pineapple Cordial on Week 1

Group1 Group2 Group3 Group4Figure 4: Appearance of Pineapple Cordial on Week 2

Group1 Group2 Group3 Group4

Figure 5: Appearance of Pineapple Cordial on Week 3

Discussion

From the results, it was found that the weights of whole fruit, cut fruit and juice extract were different for all the groups. This is due to the size of the pineapple it own at the beginning process, besides that peeling, cutting, grinding and filtering processes could explain the difference in weights because all these stages were carried out by different individuals and consequently human errors bound to occur. Because of there was no standard method of peeling and cutting the pineapples during preparation of raw material, this consequently resulted in different amount of waste especially during the removal of eyes and hence, different weights were recorded. Incomplete homogenization and inadequate filtering would reduce the amount of juice recovered. Proper handling method would minimize waste greatly and maximize the extract collected. However the concern here was not the different of the pineapple weight but the effect of different hydrocolloids pineapple cordial but these values are important in determining the amount of hydrocolloid to be used.

From the result, the percentage of yield of juice extract based on whole fruit and cut fruit was 30.80% and 62.19% for CMC added cordial, 35.87% and 73.85% for pectin added cordial, 38.87% and 69.73% for arabic gum added cordial and 31.89% and 60.03% of yield for unmodified starch added cordial.

From the data shows that there are increasing trend in °Brix value in the processing of pineapple cordial from juice to cordial. This increasing trend was normal and should increase since large amount of sugar added in the production of pineapple cordial in order to achieve the desirable sweetness and viscous texture. Mean that, the total soluble solids are increasing in the production of pineapple cordial from juice to cordial. Besides that, high concentration of sugar can lengthen the products’ shelf life. Sugar content plays an important role in the flavor characteristics and commercial assessment of pineapple fruit quality (Morton, 1987).

ºBrix value usually correlates well with perceived sweetness. The results shows that all juice extracts have ºBrix mean value approximately 9.95. ºBrix value for CMC, pectin, arabic gum and unmodified starch was 9.6, 10.3, 9.9 and 10 respectively. It shows that the pineapples used in this experiment are not fully ripened, the sugar (glucose) content in the fruit was considered low. ºBrix value of the syrup mixture for all 4 types of samples was 45.8, 45.0, 42.2, and 49.0 as it is required to prepare 45% of sugar syrup. The ºBrix value for cordial was 45.8, 45.0, 42.2, and 49.0 for sample with CMC, pectin, arabic gum and unmodified starch respectively. This was because a large amount of sugar was added and there was an increase in the concentration of dissolved solids.

Mainly the different of pH value is based on the maturity of the pineapple fruits used where more matured fruits had lower amount of tartaric acids present in them and thus caused the pH to be higher. From the result describe that pH value for fresh juice extract for CMC, pectin, arabic gum, and unmodified starch added cordial are 3.54, 3.55, 3.52, and 3.50 respectively. The pH value have no distinct different so it mean that the pineapple have almost same degree of ripening level. However, in the production of pineapple cordial in this experiment, the desirable pH value of the cordial was 3.5 – 4.0 apart from the pasteurization process carried out in the experiment. Other than that, the desirable pH also can act as a preservative rather that using pasturization because by lower pH can effectively inactivating the undesirable enzymes that caused oxidative browning and inhibited the growth of molds and yeast. Besides, the purposes of adjusting the pH of juice mixture using citric acid 3.5 to 4.0 were to help preserve the cordial by inactivating the undesirable enzymes and to add a tart flavor (Tochi et al., 2008).

As for the flavor, the most favorable cordial is which using arabic gum which shows 4.75 on average from total 5 of liked scale followed by cordial using unmodified starch which is 3.75, cordial using pectin which is 3.00 and lastly using CMC which is 2.25. As for the aroma, cordial using arabic gum and unmodified starch is shows the same result which is 4.25 which also become the most liked followed by the pectin and CMC which are 2.50 and 2.00 respectively. As for the colour attributes, the result shows that cordial using arabic gum is the most preferable which is 4.50 followed by unmodified starch which is 4.25, pectin 3.25 and the least preferable is CMC which is 2.50 on average. For the overall acceptance the most liked is cordial using arabic gum which is 4.50 followed by unmodified starch which is 4.25, pectin which is 3.0 and lastly CMC which is 2.0.

However, aside from the result, it is difficult to run the sensory evaluation because the taste and appearance of all the cordial it about the same. Besides that, while doing the sensory evaluation, the dilution of each cordial is not been standardize which ratio of water and cordial use is not the same for each group. These also give overall effect to the sensory evaluation. The panelist used is also an untrained panelist. Moreover, sensory evaluation is also subjective which means different panelist may favor different taste, aroma which gives a bias result.

Based on the result obtained in terms of viscosity, arabic gum, CMC, pectin and unmodified starch all showed inconsistent viscosity value for the past three week. Among the four types of hydrocolloid, the viscosity value for arabic gum is the lowest. Arabic gum dissolves readily in both hot and cold water. It is the least viscous and most soluble of the hydrocolloids with possible solutions approaching a 55 percent concentration possible compared with other common hydrocolloids which are limited to levels of less than 5 percent because of their high viscosities (Cho, Prosky, and Dreher, 1999). Besides that, Panda stated that viscosities of solutions of arabic gum can vary as much as 50% and are affected by pH, salts or other electrolytes, and temperatures. At concentrations below 40%, arabic gum solutions exhibit Newtonian behavior. Meanwhile, at concentrations of 40% or higher, pseudoplastic characteristics are observed, denoted by a decrease in viscosity with increasing shearing stress.

In addition, the viscosity of arabic gum is inversely proportional to temperature. When heated at less than 170˚C and then put into water, arabic gum does not dissolve, but swells to form a nonsticky gel. The viscosity of arabic gum solutions is also varies with the pH, with a maximum viscosity developing between pH 6 and 7. The viscosity of arabic gum solutions decreases with time, but this decrease can be minimized by the addition of preservatives.

Native or unmodified starch dispersed in cold water, settles out rapidly due to lack of solubility. A starch paste derived from unmodified starch has relatively high viscosity at very low solids concentration. In practice, it is nearly impossible to prepare a manageable starch paste exceeding 7% unmodified starch. With

time and temperature decrease, an increase in viscosity or thickening can be observed. This thickening is due to a well-known phenomenon for all unmodified starches called setback (Holik, 2006).

It occurs because during thermal decomposition such as gelatinization, the original crystalline arrangement of the starch molecules is lost. When cooling the starch paste, the molecules cling together again, thus forming insoluble aggregates. As a result of this crystallization process, the paste solution gradually turns turbid, while the viscosity increases. Finally, the viscous paste turns into an opaque mass or gel. In very dilute solutions, there is not enough material to gel the entire solution so insoluble starch particles sink to the bottom. It is mainly the linear amylose molecules which exert this usually undesirable tendency, called amylase retrogradation, which is an irreversible process (Holik, 2006).

In fruit juices, CMC is used as a thickener and to prevent floating or settling of fruit during preparation as well as impart clearer brighter appearance, produce desirable gel texture and reduce syneresis (Alakali, Okonkwo and Lordye, 2007).The CMC concentration that will produce good stability depends on the soluble solids content. In general, the desired amount is low since the viscosity of the product is high from the beginning. Besides that, CMC also reduces the formation of oily ring in bottlenecks (Nussivitch, 1997). It has been noted that CMC is used commercially and its solution viscosity is known to be high. Therefore, the low acid production could be attributed to its formation of highly viscous systems which caused diffusion resistance that reduced mobility of reactants (Alakali et al., 2007).

Pectin is the most utilized gelling hydrocolloid and widely used in fruit based in fruit based beverage to help provide stability. They help to prevent the formation of sediment during long term storage. The viscosity of pectin not only dependent not merely pectin concentration but also pectin type, solvent, pH, temperature and present of salts. Dilute pectin solutions are Newtonian and only slightly affected by calcium ions. Increased pH results in increased viscosity. Slat of the monovalent cations reduce pectin solution viscosity because of reduction of the high ionic strength (Nussinovitch, 1997). High molecular weight pectin molecules tend to increase viscosity and rigid pectin molecules exhibit higher viscosity than compact pectin molecules. The tertiary structure is influenced by ionic strength as increase ionic strength may result in lower viscosity because charge shielding of polymer chain (Imeson, 2010).

In terms of appearance, three types of hydrocolloid include arabic gum, CMC and unmodified starch showed the formation of two layers during week 1. Cordial produced by using arabic gum and unmodified starch consists of a clear layer on top and high viscosity at bottom. For pectin, the cordial is mixed evenly until week 2. During week 3, the cordial produced by using pectin as hydrocolloid start to form two layers with a clear layer on top and high viscosity at bottom. Meanwhile for arabic gum and unmodified starch, formation of mold is noticed. Apart from that, bubbles are formed on surface of cordial produced by using CMC.

The stabilizing effect of pectin may be explained by the positive effect of pectin on viscosity, pseudoplastic behavior and/or negatively charged f-potential (repulsive forces). In fact, pectin is basically an anionic polysaccharide which consists of a linear chain of a-D-galacturonic acid with 1–4 linkages with high molecular weight. The presence of a negatively charged can enhance the electrostatic repulsive forces between emulsion droplets. Negatively charged emulsion droplets repel each other followed by retard the aggregation and flocculation. Besides that, high acetyl content in the chemical structure of pectin could enhance the hydrophobicity of pectin followed by increase the emulsion stability of pectin-based emulsions (Mirhosseini, Tan, Aghlara, Hamid, Yusof and Boo, 2008).

Conclusion

The use of pectin and sugar in the formulation gave rise to stable jam formation. The pectin gave gelling property to the jam due to its reaction with sugar where it acted as the gelling and thickening agent. The acceptability of the jams was moderate because of the variation of heating temperature and processing time. It is best to fix a predetermined processing time and temperature to get a standard quality jam from the same procedure.

Question

1. What is the definition for fruit cordial, juice and beverage? Discuss their differences.

Fruit cordial is a sweet non-alcoholic fruit flavoured drink concentrate that is dilute with water to

taste. It shall be the soft drink composed of syrup and juice, with or without other edible portions. It

shall not contain less than 25 percent of the juice and other portions of fruit.

Fruit juice is the liquid naturally contained in fruit. Juice is prepared by mechanically squeezing or

macerating fresh fruits without the application of heat or solvents. It shall be composed of potable

water, unfermented fruit juice or unfermented mixture of the juice and other edible portions of fruits.

It shall not contain less than 35 percent of fruit juice.

Fruit beverage is any one of various liquids for drinking, usually excluding water. It is a specifically

prepared for human consumption. Beverages include both cordial and fruit juice and any other liquid

specifically prepared for human consumption.

2. State the fuction of CMC/pectin/ Arabic gum/unmodified starch. Briefly discuss other

alternatives ingredient.

CMC is Carboxymethyl cellulose that is used in food science as a viscosity modifier or thickener

and to stabilize emulsions in various products including ice-cream.

Pectin is used as gelling agent, thickening agent and stabilizer in food. The classical application is

giving the jelly-like consistency to jams or marmalades, which would otherwise be sweet juices.

Pectin is helping to regulate the flow of water in between cells and keeping them rigid.

Arabic Gum also known as gum acacia, chaar gund, char goond or meska. It is complex mixture of

polysaccharide and glycoproteins that primarily used in food industry as stabilizer. It can be used to

retard sugar crystallization in candies and confections.

Unmodified starch is general purpose starch used in many food applications as economical

thickener for food products such as soups, sauces, gravies, and puddings, where smooth viscosity or

gel formation is desired.

3. Briefly discuss the function of pasteurization in cordial processing.

Pasteurization is the process of heating liquids for the purpose of destroying harmful organism such

as bacteria, protozoa, molds and yeasts. Pasteurization is a relatively mild heat treatment, usually

performed below 100°C which is used to extend the shelf life of cordial for several months. It can

prolong the shelf life by inactivation of enzymes and destruction of relatively heat sensitive

microorganism. Pasteurization cause minimal changes in sensory characteristic or nutritional value

of the food.

Reference

Alakali, J.S., Okonkwo, T.M. and Lordye, E. M. (2007). Effect of Stabilizers on the Physico-chemical and Sensory Attributes of Thermized Yogurt. African Journal of Biotechnology, 7(2), 158-163.

Cho, S. S., Prosky, L., and Dreher, M. (1999). Complex Carbohydrates in Foods. New York: Marcel Dekker, Inc; page 337

Desai, B. B. (2000). Food of Plant Origin. In handbook of Nutrition and Diet.Florida: CRC Press. pp 231.

Holik, H. (2006). Handbook of Paper and Board. Federal Republic of Germany: WILEY-VCH; page 358 & 359

Imeson, A. (2010).Food Stabilizers, Thickeners and Gelling Agents. USA: Blackwell Publishing Ld.

Mirhosseini, H., Tan, C. P., Aghlara, A., Hamid, N. S. A., Yusof, S., & Boo, H. C. (2008). Influence of Pectin and CMC on Physical Stability, Turbidity Loss Rate, Cloudiness and Flavour Release of Orange Beverage Emulsion During Storage. Carbohydrate Polymers, 73, 83-91.

Morton, J. (1987). Pineapple. In: Fruits of warm climates. Julia F. Morton, Miami, FL. pp18-28.

Nussinovitch, A. (1997). Hydrocolloid Applications- Gum Technology in the Food and Other Industries. UK: Blackie Academic & Professional.

Panda, H.The Complete Technology Book on Natural Products (Forest Based). National Institute of Industrial Re; page 36

Sethi, V., Sethi, S., Deka, B. C., & Meena, Y. R. (2005). Processing of Fruits and Vegetables for Value Addition. New Delhi: Indus Publishing Company. pp 51.

Tochi, BN, Wang, Z, Xu, SY and Zhang, W. (2008). Therapeutic Application of Pineapple Protease (Bromelain): A Review. Pakistan Journal of Nutrition. 7(4): 513-520.

Verma, L. R. & Joshi, V. K. (2000). Postharvest Technology of Fruits and Vegetables: Handling, Processing, Fermentation and Waste Management. New Delhi: M.L. Gidwani, Indus Publishing Company. pp 682.