Quality Concentrates by Reverse Osmosis

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Quality Concentrates by Reverse Osmosis Cecilia Hodúr Katalin K. Bajúsz Mária F. Halasz Gábor Szabó

description

Quality Concentrates by Reverse Osmosis. Cecilia Hodúr Katalin K. Bajúsz Mária F. Halasz Gábor Szabó. Outline. Aims Disadvantages and Benefits of Evaporation/ RO Materials & Methods Results and Discussion Conclusions. To produce quality concentrated tomato juice, means: - PowerPoint PPT Presentation

Transcript of Quality Concentrates by Reverse Osmosis

Quality Concentrates by Reverse Osmosis

Cecilia Hodúr Katalin K. Bajúsz Mária F. Halasz Gábor Szabó

Outline

AimsAimsDisadvantages and Benefits of Disadvantages and Benefits of

Evaporation/ RO Evaporation/ RO Materials & MethodsMaterials & MethodsResults and DiscussionResults and DiscussionConclusionsConclusions

Aims

To produceTo produce quality concentrated quality concentrated tomatotomato juice, means:juice, means:

maximum flavour containminimum heat degradationminimum energy comsumption

Benefits offered byEvaporation RO

No concentration No concentration limitslimits

No thermal No thermal damagedamage

Better sensory Better sensory characteristicscharacteristics

Lower energy Lower energy consumptionconsumption

Disadvantages ofEvaporation RO

Degradation of colour due Degradation of colour due toto

• degradation of carotenoids• formation of brown

pigments • formation of black specks Changes in the flavour Changes in the flavour

volatiles volatiles • almost total loss of the

compounds typical of fresh tomatoes

• formation of off-flavours High amounts of energy High amounts of energy

requiredrequired

Limited concentrabilityLimited concentrability High Osmotic Pressure High content of

suspended solids High viscosity

Osmotic Pressure of Tomato Osmotic Pressure of Tomato Juice and SerumJuice and Serum

0

10

20

30

40

50

60

70

80

90

0 10 20 30 40 50

concentration (wt% or oBrix)

os

mo

tic

pre

ss

ure

(b

ar)

tomato juice (Ishii et al., 1981)

tomato serum (Dale et al., 1982)

Glucose (Weast, 1983)

Sucrose (Weast, 1983)

Materials & MethodsMaterials & Methods

Feed solutionsFeed solutions• Tomato serum (4,8 ref %) obtained by hot

break processing• removal of suspended solids by

centrifugation Membrane and RO moduleMembrane and RO module• tubular modul with composite polyamide

(AFC 99) membrane• containing 18 pipes, diameter: 18 mm

membrane area: 1,4 m2

RO equipmentRO equipment

Production of Tomato Paste Production of Tomato Paste by Reverse Osmosisby Reverse Osmosis

Tomato Juice

Centrifuge Serum

PulpRO

module

Water

ConcentratedSerum

Reconstitution

TomatoConcentrate

Materials & MethodsMaterials & Methods

AnalyticalAnalyticalRejection (R) %

Cf= concentration of component(s) in the feed (°Brix, wt%, ref%)

Cp= concentration of component(s) in the permeate (°Brix, wt%, ref%)

Average permeate flux (Jm)

Jm = average permeate flux (kg/m2h)

V = total amount of permeate (kg)

t = total time of permeation (h)

A = total effective surface of permeation (m2)

100C

CCR%

f

pf At

VJm

• Physical analysesPhysical analyses• Rheological analysis

• k - consistency• n - flow index

• Coulour analysis• a* - yellowness• b* - redness

• Sensorial analysis• Poretta’s method

Materials & MethodsMaterials & Methods

Permeate flux and Feed Permeate flux and Feed concentration vs. time concentration vs. time

(25°C, 70 bar)(25°C, 70 bar)

y = 1,486x + 2,2576

R2 = 0,9525

y = 104,52x-0,9328

R2 = 0,9810

20

40

60

80

100

120

0 10 20 30 40 50 60 70 80 90 100 110

time [min]

flux

[kg

m-2

h]

0

5

10

15

20

25

qm [kg/m2h]

ref %

Lineáris (ref %)

Hatvány (qm[kg/m2h])

y = 104,52x-0,9328

R2 = 0,981

0

20

40

60

80

100

120

5,25 6,25 7 8 8,75 10 11,25 12,5 15 17,25 19,75 22

feed concentration [%]

flux

[kg

m-2

h]

qm [kg/m2h]

Hatvány (qm[kg/m2h])

Permeate flux vs. Permeate flux vs. Feed concentration Feed concentration

(25°C, 70 bar)(25°C, 70 bar)

Newtonian fluid

0

0,5

1

1,5

2

2,5

3

3,5

4

4,5

viscisity [mPas]

row juice hot breaked

serum concentrate water

Flow curve of concentrate

0 30 60 90 120 150D (1/sec)

0

10

20

30

40

50

tang.stress(Pa)

k = 13.787n = 0.256

t = 20 0C

Redness values (a*/b*)

0

0,5

1

1,5

2

2,5R

ow

juic

e

fib

re

seru

m

con

cen

trat

e

Reb

len

ded

Co

mm

erci

al

sam

ple

Specific energy comsumption

time [min]

feed conc. [%] specific energ.consumption [kJ/kg]

0

5

10

15

20

25

1 1325 37 496173 85 97 109 133 157 181 205 24 5 277 0

500

1000

1500

2000

2500

3000

ref %

Spec.energ. kJ/kg

Sensorial analysis

Concentrate Commercial sample 1 Commercial sample 2

Acidity1= acidical

9= non acidical

8 8 6

Natural flavour1= different

9= fresh tomato

8 5 4

Colour1= heterogen

9=perfect

9 7 6

Viscosity1=flow9=rigid

8 9 5

Total value 33 29 21

Thank you for your attention

The authors are grateful to the Hungarian Government „NKFP 4/0026” project for supporting this work.