Adjusting acid, pectin and sugar and cooking concentration, module 3

COMPETENCY-BASED LEARNING MATERIAL

PROCESSED FOOD AND BEVERAGE SECTOR

FOOD PROCESSING TECHNICIAN NC Level III

Module 3
ADJUSTING ACID, PECTIN AND SUGAR AND
COOKING CONCENTRATION

LEARNER’S GUIDE

Unit of Competency:
PROCESS FOOD BY SUGAR CONCENTRATION

HOW TO USE THIS COMPETENCY-BASED LEARNING MATERIAL

Welcome to the module in Adjusting Acid, Pectin and Sugar and Cooking
Sugar Concentration. This module contains training materials and activities for you to
complete.

The unit of competency “Process Food by Sugar Concentration” contains
knowledge, skills and attitudes required for Food Processing. It is one of the
specialized modules at National Certificate level (NC III).

You are required to go through a series of learning activities in order to complete
each learning outcome of the module. In each learning outcome are Information
Sheets and Resource Sheets (Reference Materials for further reading to help you
better understand the required activities). Follow these activities on your own and
answer the self-check at the end of each learning outcome. You may remove a blank
answer sheet at the end of each module (or get one from your facilitator/trainer) to write
your answers for each self-check. If you have questions, don’t hesitate to ask your
facilitator for assistance.

Recognition of Prior Learning

You may have some or most of the knowledge and skills (RPL) covered in this
learner’s guide because you have:

 been working for some time
 already completed training in this area.

If you have demonstrated to your trainer that you are competent in a particular skill,
you don’t have to do the same training again.

If you feel you have some of the skills, talk to your trainer about having them
formally recognized. If you have qualification or Certificate of Competence from
previous training, show it to your trainer. If the skills you acquired are still relevant to
the module, they may become part of the evidence you can present for RPL.

This module was prepared to help you achieve the required competency in
processing food by sugar concentration. This will be the source of information for you to
acquire knowledge and skills in this particular trade, with minimum supervision or help
from your instructor. With the aid of this material you will acquire the competency
independently and at your own pace.

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 Talk to your trainer and agree on how you will both organize the Training of this
unit. Read through the learning guide carefully. It is divided into sections, which
cover all the skills, and knowledge you need to successfully complete in this
module.

 Work through all the information and complete the activities in each section.
Read information sheets and complete the self-check. Suggested references are
included to supplement the materials provided in this module.

 Most probably your trainer will also be your supervisor or manager. He/she is
there to support you and show you the correct way to do things. Ask for help.

 Your trainer will tell you about the important things you need to consider when
you are completing activities and it is important that you listen and take notes.

 You will be given plenty of opportunity to ask questions and practice on the job.
Make sure you practice your new skills during regular work shifts. This way you
will improve both your speed and memory and also your confidence.

 Talk to more experienced workmates and ask for their guidance.
 Use the self-check questions at the end of each section to test your own

progress.
 When you are ready, ask your trainer to watch you perform the activities outline

in the learning guide.
 As you work through the activities, ask for written feedback on your progress.

Your trainer keeps feedback/pre-assessment reports for this reason. When you
have successfully completed each element, ask your trainer to mark on the
reports that you are ready for assessment.
 When you have completed this module (or several modules), and feel confident
that you have had sufficient practice, your trainer will arrange an appointment
with registered assessor to assess you. The results of your assessment will be
recorded in your competency Achievement Record.

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QUALIFICATION : FOOD PROCESSING NC III
Process Food by Sugar Concentration
UNIT OF COMPETENCY : Adjusting Acid, Pectin and Sugar and Cooking
Concentration
MODULE :

INTRODUCTION:

Good jelly contains pectin, sugar and acid dissolved in water, each contributing a
definite relationship to all of the other ingredients. To obtain a good quality product
requires considerable skills in determining the jellying qualities of the fruit, the proportion
of sugar to use, and the degree of cooking necessary.

Found in the juice are flavoring substances, some minerals, natural fruit sugars,
pigments and pectic substances. Only the juice is used in jelly making and therefore it is
the soluble substance of the fruit that determine its jellying power.

This module deals with the knowledge, skills and attitude required in adjusting
acid, pectin, sugar and cooking sugar concentrate.

After completing this module, you will be assessed through written tests and
demonstration of safety preparatory operations involved in fruits and vegetables
processing.

LEARNING OUTCOMES

At the end of this module, you will be able to:

1. Measure the required amount of pectin, sugar and acid.

2. Mix measured pectin, acid and sugar with the prepared fruit pulp/juice
extract/ pieces of fruit.

3. Cook mixture to required consistency.

ASSESSMENT CRITERIA:

1. Required amount of pectin, sugar and citric acid are measured according to
approved specification.

2. Analysis of required amount of pectin, sugar and acid.
3. Measured pectin, acid and sugar are mixed with chopped fruit pulp/juice

extract/pieces of fruits according to recipe.
4. Mixture is heated and boiled/cooked to required consistency according to recipe.
5. Desired end point is checked/ tested.

PRE-REQUISITE: National Certificate II

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Sugar Concentrate June 2005 December 2005

QUALIFICATION : FOOD PROCESSING NC III

UNIT OF COMPETENCY : Process Food by Sugar Concentration

MODULE : Adjusting Acid, Pectin and Sugar and Cooking

Concentration

LEARNING OUTCOME #1 : Measure the required amount of pectin, sugar and
acid

ASSESSMENT CRITERIA:

1. Required amount of pectin, sugar and citric acid are measured according to
approved specification.

2. Analysis of required amount of pectin, sugar and acid.

RESOURCES: Tools and Instruments Supplies &Materials
Refractometer
Equipment and Facilities Candy Thermometer
Stove/Burner Jelly Thermometer
Casserole
Wooden ladle
Measuring Spoon/Cup

REFERENCES:

1. De Leon, S.Y. and Guzman M.P. 1998. Preservation of Philippine Foods, A
Manual of Principles and Procedures.

2. Gatchalian, M. M. and S. De Leon. 1992. Introduction to Food Technology
3. Gonzales, Olympia N., et. al. 1982. Philippine Handbook on Canned Low Acid

Foods. A project of NSDB-NIST and No. 7801. National Institute of Science and
Technology Authority.
4. Lopez, A. 1981. A Complete Course in Canning-Processing Procedures for
Canned Products. The Canning Trade. Baltimore Maryland, USA:
5. Preservation of Fruits and Vegetables.1983. Laboratory Services Division,
Bureau of Plant Industry.

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Learning Experiences
Learning Outcome #1: Measure the required amount of pectin, sugar and acid.

LEARNING ACTIVITIES SPECIAL INSTRUCTIONS

1. Read Information Sheet # 1-1: Information Sheet # 1-1: “Functions of
“Functions of Ingredients in jelly Ingredients in jelly Preservation”

Preservation

2. Read Information Sheet # 1-2: Information Sheet # 1-2:

“Adjustment of Sugar and Acid “Adjustment of Sugar and Acid
Concentration” Concentration”

3. Perform Job Sheet # 1-1: Job Sheet # 1-1:
Determining the pectin, sugar and acid Determining the pectin, sugar and acid
content of fruits
content of fruits

4. Perform Self Check #1-1 Self Check #1-1

5. Check your answers using the answer Answer Key #1-1
key # 1-1

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Cooking Sugar Concentrate June 2005 December 2005 Page 5

INFORMATION SHEET # 1-1

Function of Ingredients in Jelly Preservation

1. Fruit. Fruits for jelly making should have full flavor and should have full flavor. It
should contain sufficient pectin and acid. Jelly formation is possible only with the
proper pectin-to sugar acid ratio.

2. Pectin – a water soluble substance found in some slightly under ripe fruits that
causes jellies to set. Under is capable of forming a gel when sugar and acid are in
the right proportions. Some local fruits which have high pectin content are guava,
guyabano, santol, siniguelas, breadfruit, anonas and chico.

Pectin content of fruits are determined by the following methods:

1. Cooking test. Boil a small amount of juice with sugar. If the mixture gels, then it
is rich in pectin.

2. Alcohol test. Mix one tablespoon of sugar with two tablespoon of denatured
95% wood alcohol. The pectin content would be determined by the nature of
precipitate. Presence of transparent jelly –like lump, denotes that the fruit is
rich in pectin. Jelly-like clot is not very firm and is broken into two or more
lumps, then the fruit juice has moderate amount of pectin. If the clot is broken
into numerous small pieces or the juice becomes cloudy, then the fruit juice
has very little pectin content.

3. Jelmeter test. An instrument similar to a graduated pipette, where the juice of
the fruit is allowed to run down the jelmeter tube for one minute to test the
pectin content.

Pectin-rich juice – thicker and runs down the tube more slowly that
the juice with little pectin.

Low pectin juice- runs below the one-half (1/2) mark of the jelmeter
after one minute has a low pectin content.

4. Acid. It makes the jelly firm and rigid in structure and is essential for flavor and gel
formation. Gel formation occurs from 2.5 to 3.5 pH. Ideal pH value for gel formation
is pH 3.2. Fruits differ in acidity and if the fruits used for jelly making lacks acid
jellying maybe improved by adding commercial citric or tartaric acid or calamansi or
lemon juice.

5. Sugar. The precipitating agent of pectin causing it to form the network of the jelly.
Like acid, it controls the rigidity, strength of the jelly while acting as preservative at
the same time. Amount of sugar added depends upon the acid and pectin content of
the juice. More acid in a solution, less sugar is required. High pectin content requires
more sugar. Adding ¾ cup of sugar is recommended. Less than this would give
lower jelly strength. Always remember to add sugar to the juice before boiling.

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Pectin- Rich Fruits

Local Name Part Used Total Pectin
(Calcium Pectate on a

fresh Basis)

Anonas Pulp, ripe 2.14
Peelings, ripe 2.10
Bayabas, green Pulp, unripe 2.03
Bayabas, pula Whole fruit, ripe 1.41
Kamatis Whole fruit, unripe 1.92
Granada Whole fruit, ripe 1.52
Whole fruit, unripe 1.18
Guyabano Whole fruit, ripe 0.21
Lokwat Whole fruit, unripe 0.72
Pulp, ripe 2.95
Papaya Seeds, ripe 1.89
Pili pulp Pulp, unripe 3.08
Rimas Seeds, unripe 1.60
Saging, bungulan Pulp, ripe 2.14
Saging, butuan Pulp, unripe 1.77
Saging, Gloria Pulp, ripe 1.15
Saging, lakatan Peelings, ripe 4.72
Saging, latundan Pulp, unripe 1.75
Saging, morado Peelings, unripe 5.31
Saging, saba Pulp, ripe 1.95
Saging, ternate Pulp, unripe 3.32
Santol Pulp, ripe 3.06
Siniguelas Pulp, unripe 3.34
Pulp, ripe 1.87
Pulp, unripe 3.96
Pulp, ripe 1.11
Pulp, unripe 0.88
Pulp, ripe 1.49
Pulp, unripe 2.03
Pulp, ripe 0.49
Pulp, unripe 0.48
Pulp, ripe 2.08
Pulp, unripe 1.78
Pulp, ripe 1.05
Pulp, unripe 2.97

Pulp, ripe 1.30
Pulp, unripe 1.42
Pulp, ripe 1.72
Pulp, unripe 1.58
Pulp, ripe 0.93
Pulp, unripe 0.95
Pulp, ripe 2.63
Pulp, unripe 2.50
Pulp and skin, ripe 2.52

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INFORMATION SHEET #1-2

Adjustment of Sugar and Acid Concentration

Jams, jellies and syrups must have the right sugar concentration. Fruit juices
on the other hand, must have the desired sugar acid proportion to give the best
quality canned fruit products. Hence, knowing how to determine and adjust the sugar
and acid concentration is imperative in canning of fruits.

A. Brix/Acid Ratio

The Brix/Acid Ratio is a sweetness-to-tartness relationship. It gives a ratio
compared with unity which forms a comparative scale for the acceptability of juice
concentrates. The Brix unit is the concentration of dissolved solids in an aqueous
solution or the % Soluble solids (%SS). The acid unit is the concentration of citric
acid in the citric juice.

B. Methods for Calculating Brix/Acid Ratio

1. Sugar Concentration

The Pearson’s Square is a widely used method for determing and
calculating the degree Brix. It is as follows:

Initial % SS % Purity of Sugar

Desired SS

(b) Difference between % purity (a) Difference between
or sugar and desired % SS initial % SS and
desired % SS

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The % purity of pure sucrose is assumed to be 100%. If syrup is used, the
concentration of the syrup will be used, say a 65% syrup. Water is 0% SS. Given
a certain weight of juice or water, the weight of sugar to be added to obtain the
desired % SS may be obtained by the formula:

a x (weight of juice or water) = required amount of sugar
b to be added

Example 1

Problem : How much sugar is necessary to add to 20 kg of water to make a
35° Brix syrup?

Solution : % SS of water 0
% purity of sugar 100
Weight of water 20 kgs.
Required °Brix 35°B

0° 100%

35°

65° 35°

35 x 20 = 10.8 kgs. sugar
65

2. Acid Concentration

The % acid of fruit juices is called the % tritatable acidity. Tritatable is an
important flavor quality factor. The product may be rejected if too high in acid, if
too low flavor is bland and unappealing. Hence, adjusting fruit juices to the
desired acidity is important.

The % acidity of fruit juices can be determined by titration. A certain
weight of sample is tritatable with 0.1 Normal sodium hydroxide solution to light
pink in color.

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The acidity can be calculated by the formula:

% Acid = Volume of NaOH x Normality of NaOH x 0.6 x 100
Weight of sample

Knowing the initial % acid, the fruit juice can be adjusted to the desired
acidity by using the Pearson’s Square:

% Initial acid % purity of citric acid

Desired Acid

(a) Difference between (b) Difference between
Initial% acid and % purity of acid
desired % acid and desired % acid

Example 1 15%
3.2%
Solution : % initial acid
Desired acid 100%
% purity of citric acid 20 kg
weight of juice

15% 100%

3.2%

11.8% 96.8%

11.8% x 20 kg
96.8%

0.122% x 20 kg = 2. 44 kg

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Job Sheet # 1-1

Job Title : Determining the pectin, sugar and acid content of fruits

Purpose : To be able to determine the pectin, sugar and acid content of
available fruits.

Conditions or
Situations for the Job :

Equipment, Tools and

Materials : Raw material: Fruits, Water

Instruments: Jelmeter, pH meter and Refractometer

Precautions : Be careful in handling sharp and fragile objects.

Procedure :

1. Each participant will be provided with fruits for this activity.
2. Extract the juice of the fruit following the procedure provided in information sheet
3. After extraction, determine the pectin, sugar and acid content of your raw

materials following the test methods and using an apparatus.

Pectin content of fruits are determined by the following methods:

a. Cooking test.
Boil a small amount of juice with sugar. If the mixture gels, then it is rich in pectin.

b. Alcohol test.
Mix one tablespoon of sugar with two tablespoon of denatured 95% wood
alcohol. The pectin content would be determined by the nature of precipitate.
Presence of transparent jelly –like lump, denotes that the fruit is rich in pectin.
Jelly-like clot is not very firm and is broken into two or more lumps, then the fruit
juice has moderate amount of pectin. If the clot is broken into numerous small
pieces or the juice becomes cloudy, then the fruit juice has very little pectin
content.

c.Jelmeter test.
An instrument similar to a graduated pipette, where the juice of the fruit is
allowed to run down the jelmeter tube for one minute to test the pectin content.

Pectin-rich juice – thicker and runs down the tube more slowly that
the juice with little pectin.

Low pectin juice- runs below the one-half (1/2) mark of the jelmeter
after one minute has a low pectin content.

d. Using a Refractometer

Put one or two drops of sample on the prism.

Look at the scale through the eyepiece.

Read the scale. Record the result.

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e. Using a pH meter
In some pH meter models, pH values are read directly.
Note: The pH plays a critical role in jellymaking. Pectin can form a gel with sugar
only at ph 3.2. At lower pH 2.5, syneresis will occur and above 3.5 the jelly will
not form.

4. When you are ready, call your Instructor to evaluate your results and rate your
skill.

5. After the evaluation, store your fruit juices/fruit pulp in the refrigerator for use in
your next laboratory exercise.

Code No. Adjusting Acid, Pectin and Sugar and Cooking Date: Developed Date: Revised Page 12

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SELF CHECK #1-1

Computing the right amount of Sugar and Acid for Sugar Concentration.

Objective: To be able to compute the right amount of Sugar and Acid needed for
processing sugar concentrate products.

Problem 1:
A 10 kg mango puree has an initial Total Soluble Solids (TSS) of 18° Bx. How much
sugar must be added to adjust its concentration to 20° Bx?

Solution: Initial TSS of puree 18°Bx
Desired TSS of puree 20°Bx
Weights of puree 10 kg
% Purity of sugar 100%

Problem 2:

A 50 kg juice has an initial concentration of 35°Brix. How much sugar must be added to
prepare a 55°B juice concentrate?

Solution: Initial SS 35°B
Desired SS 55°B
Weight of juice 50 kg
% Purity sugar 100%

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Problem 3:

How much acid is required to adjust the desired acidity of the fruit weighing 10 kg?

Solution: % initial acid 10%
Desired acid 2.5%
% purity of citric acid 100%
weight of juice 10 kg

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Problem 4 :

How much acid is required to adjust the desired acidity of the fruit weighing 25 kg?

Solution: % initial acid 30%
Desired acid 3.0%
% purity of citric acid 100%
weight of fruit puree 25 kg

Enumeration:

1. Name the ingredients in Jelly processing.

a.
b.
c.
d.

2. Methods for determining the pectin content of fruits.

a.
b.
c.

3. Instruments used in sugar concentrates

a.
b.
c.

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4. Name five (5) local fruits rich in pectin

a.
b.
c.
d.
e.

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Answer Key #1-1

Problem 1: A 10 kg mango puree has an initial Total Soluble Solids (TSS) of 18° Bx.
How much sugar must be added to adjust its concentration to 20° Bx?

Solution : Initial TSS of Puree 18° Bx
Desired TSS of Puree 20° Bx
Weight of Puree 10 kg
% purity of sugar 100

18° Bx 100

20°Bx

80 2

2
X 10 kg = 2.5 kg

80

Problem 2:

A 50 kg juice has an initial concentration of 35°Brix. How much sugar must be added to
prepare a 55°B juice concentrate?

Solution: Initial SS 35°B
Desired SS 55°B
Weight of juice 50 kg
% Purity sugar 100%

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35° Bx 100%

55° Bx

45 20

20
X 50 kg = 22.22 kg sugar must be added to the juice to

45 achieve the desired SS of 55° Bx

Problem 3:

How much acid is required to adjust the desired acidity of the fruit weighing 10 kg?

Solution : % initial acid 10%
Desired acid 2.5%
% purity of citric acid 100%
weight of juice 10 kg

10% 100

2.5

7.5 97.5

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7.5
X 10 kg = 0.77 kg

97.5

Problem 4 :

How much acid is required to adjust the desired acidity of the fruit weighing 25 kg?

Solution : % initial acid 30%
Desired acid 3.0%
% purity of citric acid 100%
weight of fruit puree 25 kg

30% 100

3.0 %

97 27

27
X 50 kg = 6.96 kg

97

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Sugar Concentrate June 2005 December 2005

Enumeration

1. Name the ingredients in Jelly processing.

a. Fruits
b. Pectin
c. Sugar
d. Acid

2.Methods for determining the pectin content of fruits.

a. Cooking Test
b. Alcohol Test
c. Jelmeter Test

3. Instruments used in sugar concentrates

a. Jelmeter
b. Refractometer
c. pH meter

4. Name five (5) local fruits rich in pectin

a. Guava.
b. Guyabano
c. Siniguelas
d. Santol
e. Chico

Code No. Adjusting Acid, Pectin and Sugar and Cooking Date: Developed Date: Revised Page 24

Sugar Concentrate June 2005 December 2005

QUALIFICATION : FOOD PROCESSING NC III

UNIT OF COMPETENCY : Process Food by Sugar Concentration

MODULE : Adjusting Acid, Pectin and Sugar and Cooking Sugar

Concentrate

LEARNING OUTCOME #2 : Mix measured pectin, acid and sugar with the
prepared fruit pulp/juice extract/pieces of fruits.

ASSESSMENT CRITERIA:

1. Measured pectin, acid and sugar are mixed with chopped fruit pulp/juice
extract/pieces of fruits according to recipe.

2. Different tools, equipment, apparatus and utensils to process food by sugar
concentration are properly air dried and stored.

RESOURCES:

Equipment and Facilities Tools and Instruments Supplies &Materials
Stove/Burner Refractometer
Candy Thermometer
Jelly Thermometer
Casserole
Wooden ladle
Measuring Spoon/Cup

References:

1. De Leon, S.Y. and Guzman M.P. 1998. Preservation of Philippine Foods, A
Manual of Principles and Procedures.

2. Gatchalian, M. M. and S. De Leon. 1992. Introduction to Food Technology
3. Gonzales, Olympia N., et. al. 1982. Philippine Handbook on Canned Low Acid

Foods. A project of NSDB-NIST and No. 7801. National Institute of Science and
Technology Authority.
4. Lopez, A. 1981. A Complete Course in Canning-Processing Procedures for
Canned Products. The Canning Trade. Baltimore Maryland, USA:
5. Preservation of Fruits and Vegetables.1983. Laboratory Services Division, Bureau
of Plant Industry.

Code No. Adjusting Acid, Pectin and Sugar and Cooking Date: Developed Date: Revised Page 21

Sugar Concentrate June 2005 December 2005

Learning Experiences

Learning Outcome #2: Mix measured pectin, acid and sugar with the prepared fruit
pulp/juice extract/pieces of fruits.

LEARNING ACTIVITIES SPECIAL INSTRUCTIONS
1. Read Information Sheet # 2-1:  Information Sheet # 2-1:
“ Temperature Correction Table “
Temperature Correction Table
2. Read Information Sheet # 2-2:
“Controlling the Variables in a Pectin Gel”  Information Sheet # 2-2:
“Controlling the Variables in a
3. Perform Job Sheet #2-1 Pectin Gel

 Job Sheet # 2-1

4. If you feel you already achieved the  Self Check # 2-1
learning outcome, do self-check # 2-1

5.Check your answer using the answer  Answer Key #2-1
key # 2-1

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INFORMATION SHEET # 2-1

TEMPERATURE CORRECTION TABLE

Temperature corrections for reading of per cent sucrose in sugar solution by either
Abbe or Immersion refractometer at temperature other than 20°C

International Temperature Correction Table, 1936*

Temperature 0 PERCENT SUCROSE 60 70
(°C) 5 10 15 20 25 30 40 50
0.54 0.76 0.79
10 0.50 0.49 SUBTRACT FROM PERCENT SUCROSE 0.74 0.69 0.71
11 0.46 0.45 0.58 0.61 0.64 0.66 0.68 0.72 0.67 0.61 0.63
12 0.42 0.40 0.53 0.55 0.58 0.58 0.62 0.65 0.60 0.54 0.55
13 0.37 0.35 0.48 0.50 0.52 0.52 0.56 0.58 0.53 0.46 0.48
14 0.33 0.42 0.44 0.46 0.46 0.49 0.51 0.45
0.37 0.39 0.40 0.40 0.42 0.44

15 0.27 0.29 0.31 0.33 0.34 0.34 0.35 0.37 0.38 0.39 0.40
16 0.22 0.24 0.25 0.26 0.27 0.27 0.28 0.30 0.30 0.31 0.32
17 0.17 0.18 0.19 0.20 0.21 0.21 0.21 0.22 0.23 0.23 0.24
18 0.12 0.13 0.13 0.14 0.14 0.14 0.14 0.15 0.15 0.16 0.16
19 0.06 0.06 0.07 0.07 0.07 0.07 0.07 0.08 0.08 0.08 0.08

ADD FROM PERCENT SUCROSE
21 0.06 0.07 0.07 0.07 0.07 0.08 0.08 0.08 0.08 0.08 0.08
22 0.13 0.13 0.14 0.14 .15 0.15 0.15 0.15 0.16 0.16 0.16
23 0.19 0.20 0.21 0.22 0.22 0.23 0.23 0.23 0.24 0.24 0.24
24 0.26 0.27 0.28 0.29 0.30 0.30 0.31 0.31 0.31 0.32 0.32
25 0.33 0.35 0.36 0.37 0.38 0.38 0.39 0.40 0.40 0.40 0.40

26 0.40 0.42 0.43 0.44 0.45 0.46 0.47 0.48 0.48 0.48 0.48
27 0.48 0.50 0.52 0.53 0.54 0.55 0.55 0.56 0.56 0.56 0.56
28 0.56 0.57 0.60 0.61 0.62 0.63 0.63 0.64 0.64 0.64 0.64
29 0.64 0.66 0.68 0.69 0.71 0.72 0.72 0.73 0.73 0.73 0.73
30 0.72 0.74 0.77 0.78 0.79 0.80 0.80 0.81 0.81 0.81 0.81

* International Sugar J. 39, 24S (1937)

Source:

Association of Official Analytical Chemists (AOAC), Official Methods of Analysis, 14th
Edition. 1984. AOAC, Inc. Virginia, U.S.A

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INFORMATION SHEET #2-2

CONTROLLING THE VARIABLES IN A PECTIN GEL

Production of a pectin gel requires that the concentration of constituents be
balanced in the finished product. The proportions of hydrogen ions, sugar, salts, and
pectin determine whether a gel will form and, if so, the temperature at which it begins to
set and the quality of the gel. The concentration of each can vary, but within restricted
limits. A slight excess of one variable may compensate for a slight deficiency of another.
Except for this, failure in jelly making would be far more common.

Hydrogen-Ion Concentration

Most fruit pectins will form a gel at a hydrogen-ion concentration that falls within the
pH range of 2.8 to 3.4. Unless the pH is below 3,5, a gel is unlikely to form. The hydro-
gen-ion concentration that is optimum for gel formation varies with the quality of the
pectin, especially with its methoxyl content, with the salts present in the fruit extract, and
with the concentration of sugar in the finished jelly. A pH meter is required to measure
the hydrogen-ion concentration of a pectin sol. A rough estimate of the acidity of a
pectin extract may be made by comparing its tartness with that of one volume of lemon
juice diluted with eight volumes of water. Lemon juice (pH 2.2 to 2.4) is usually used to
supplement the acidity of fruits that are lacking in tartness, although tartaric acid is more
effective than citric acid in promoting gel formation because it is more highly ionized.
Although acid is required for pectin gel formation, in excess it gives a brittle gel that is
subject to syneresis.

Sucrose Concentration

The higher the methoxyl content of the pectin, the higher the ratio of sucrose
required to effect gelation. The concentration of sucrose required to form a gel may be
as low as 40 percent or as high as 70 percent, but it usually falls within the range of 60
to 65 percent. A 60-percent sucrose solution boils at 103°C (217°F); a 65-percent
sucrose solution boils near 104°C (219°F); one that boils near 105°C (221°F) has a
sugar concentration near 68 percent. This means that most pectin gels form when the
sugar concentration is sufficient to raise the boiling point of the mixture to 103° to 105°C
(217° to 221°F). The precise concentration that is optimum depends upon the particular
pectin molecules involved, the hydrogen-ion concentration of the pectin sol, and the
salts present. For cranberries to gel the concentration of sugar must be kept below 60
percent. This is due in part to the low pH of cranberries. Unripe gooseberries, which are
equally tart, require less than a 60-percent sugar concentration for gel formation, also. A
67-percent sucrose solution is saturated at room temperature (20°C or 68°F). Inversion
of part of the sucrose by acid as the jelly boils plus the presence of pectin prevent the
precipitation of sucrose crystals in jelly that has been boiled to 105°C (221°F) or higher.
Sucrose crystals may form in jellies made with a commercial pectin concentrate that

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requires a boiling time too short (one minute) for sufficient inversion of sucrose to
take place.

Two ways are available to control the concentration of sugar in finished jelly. The
mixture may be boiled to a predetermined weight, which is calculated on the basis of the
weight of sugar combined with the fruit pectin extract. Alternately, the boiling point of the
jelly may be used as an index to the sugar concentration (and doneness) of the jelly, as
is the practice for candies and frostings.

Pectin Concentration

The concentration of pectin in finished jelly usually varies between 0.5 and 1
percent. A cranberry jelly with a pectin content of 0.18 percent is atypical. Cranberries
contain pectin of unusually high quality and low pH (2.7 to 2.9).

When pectin is extracted from fruit with hot water, the quantity and sugar-carrying
capacity of the pectin is unknown. If more sucrose is combined with this extract than the
pectin it contains requires, and the mixture is then boiled until the sucrose is sufficiently
concentrated (103° to 105°C or 217° to 221°F), the pectin will be insufficiently
concentrated and either a weak gel or no gel forms. If, instead, this mixture is boiled
until enough water has evaporated so that the pectin is sufficiently concentrated, a jelly
can form but it will be sticky and sucrose may crystallize from the supersaturated
solution. If the volume of sugar that is combined with the extract is insufficient for the
sugar-carrying capacity of the pectin, the pectin will become too concentrated by the
time sufficient water is evaporated to concentrate the sucrose. A stiff jelly is the result.
Even when sucrose is combined with the extract in proportion to the gel-forming
potential of its pectin, no gel or a weak one results if insufficient water is evaporated
(boiling point of the mixture too low) or a stiff gel results if too much water is evaporated
(boiling point of the mixture too high). The effects of the variables discussed above on
the quality of fruit pectin jellies are summarized in Table 1.

Despite the hurdles, it is possible to make high quality pectin jelly with a fruit pectin
extract. Determining the sugar-carrying potential of the pectin extract is essential. One
sure way to do this is to make a series of test jellies, varying the proportions of sugar
and possibly the amount of acid. Of course, this is impractical when jelly is made in
small quantities. An estimate of the jelly-forming capacity of the pectin in an extract can
be obtained by precipitating the pectin. To do this, two volumes ofethanol are added to
one volume of the extract in a test tube or graduated cylinder that is slowly inverted and
then up-righted. The size and coherence of the precipitated pectin gives some indication
of the sugar-carrying and gel-forming potential of the pectin extract.

The viscosity of a fruit pectin extract is a better index of its sugar-carrying capacity;
the more concentrated the pectin, the more viscous is the extract. In addition, the higher
the molecular weight of the pectin and the higher the proportion of methyl groups with
their water cages, the more viscous is the dispersion and the higher the proportion of
sucrose necessary to effect gel formation.

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Effects of Variables on Fruit Pectin Jellies

Ratio of Sugar to Pectin Test for Doneness Effect(s) on Jelly

In excess Jelly boiled to 103°- No gel or weak one
Too low
105°C Sticky jelly; sucrose may
Optimum
Jelly boiled to give crystallize

sheet test

Jelly boiled to 103°- Jelly firm and rubber-like

105°C

Jelly boiled to give

sheet test

Jelly boiled above Firm gel; slightly sticky

105°C No gel or a weak one

Jelly boiled to less than

103°C

A Jelmeter may be used to measure the viscosity of a pectin sol. This device is an
adaptation of a viscometer. It consists of a small test tube to the lower end of which is
attached a fine capillary tube. When liquid is confined and allowed to flow through a
narrow space like the bore of the capillary, the flow pattern is described as laminar. As
molecules of water flow through the capillary, they move in columns that slide past each
other in telescopic fashion. The symmetrical shape of water molecules (essentially
spherical) favors this laminar flow. The long, asymmetrical molecules of pectin
interspersed among the molecules of water disrupt this flow. As a result, the molecules
of dispersing liquid are delayed in their passage through the capillary. A liquid with a
slower rate of flow is more viscous. The greater the concentration of pectin molecules
and, even more important, the greater the length of the pectin molecules, the more
viscous is the pectin sol and the higher its sugar-combining capacity. If the extract
needs acid, it should be added before the viscosity is measured. The extract should be
at room temperature when the test is made. If the extract is too warm, the flow is
speeded; if at refrigerator temperature, it is retarded. In either case, a false reading
results.

To make the test, the Jelmeter is filled with the pectin sol. The sol is allowed to flow
from the Jelmeter for exactly one minute. The upper tube of the Jelmeter is calibrated to
read in cups of sugar per cup of fruit pectin extract. The first mark below the top of the
Jelmeter, which reads 1¼ cups, is for the most viscous sol. One that is more viscous,
that is, flows less than this distance in the time specified should be diluted with water or
a juice free of pectin. Otherwise the fruit pectin extract cannot dissolve enough sugar for
the jelly-forming potential of the pectin present. A pectin sol that flows so fast that it
goes below the lowest mark, which indicates ½ cup of sugar per cup of pectin sol, is too
low in jellying power to make satisfactory jelly without the addition of pectin concentrate.

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SETTING TIME AND TEMPERATURE

All pectin gels do not begin to set at the same temperature. High methoxyl pectins
with 70 to 80 percent of carboxyl groups esterified are rapid setting (i.e., have a high
setting temperature). Slow setting pectins with 65 to 75 percent of the carboxyl groups
as methyl esters must be cooled to a lower temperature before a gel begins to form. As
a jelly mixture cools, a temperature is reached first that favors hydrophobic interaction
between methyl groups. With additional cooling, a temperature is arrived at that favors
hydrogen bonding between polar groups. Factors in addition to the pectin influence the
setting time of a gel. The higher the concentration of hydrogen ions (the lower the pH)
and the higher the concentration of solute the higher the setting temperature. If the
setting temperature is too near the boiling point of the mixture, a gel may begin to form
as the mixture is poured. Disruption of a gel, once it starts to form, weakens the final
product. Manufacturers circumvent this problem by adding the hot mixture to the acid in
the jelly glass. To prevent premature gelation of cranberry pectin gel, the sucrose
concentration should be kept below 60 percent.

JELLY MADE WITH PECTIN CONCENTRATE OR POWDER

Use of either commercial product provides more control over the variables in jelly.
Both forms of pectin contain sufficient acid. The volumes of sugar and of fruit juice
specified in the directions that accompany each product are such that pectin, sugar, and
hydrogen ions are in balance when the ingredients are combined. Low methoxyl
pectins, including ami-dated pectin in which an (—NH2) group replaces an (—OCH3)
group are available that will form jelly with reduced sugar content. The short boiling
period of these products serves only to dissolve the sugar and disperse the pectin.
Sugar is dissolved in the fruit juice before liquid pectin is added, but powdered pectin is
first dispersed in the fruit juice and then the sugar is added. The boiling period is too
short to hydrolyze the sugar, but it does maintain fruit flavor.

JELLY MADE WITH FRUIT PECTIN EXTRACT

Extraction of Pectin

Fruits that are just ripe or slightly under ripe should be used. However, unripe apples
should not be used because the starch that is present makes the jelly cloudy. Some
fully ripe fruit may be included for color, aroma, and taste. Soft fruits should be crushed
and firm fruits sliced thinly or chopped to facilitate extraction of pectin. If the fruit lacks
sufficient tartness to make jelly, acid is added at this point because it aids in the
extraction of pectin with high jellying power. Thin slices of lemon, minus the yellow part
of the rind, may be cooked along with the fruit. The pulp supplies acid, and the albedo
supplies pectin. Water is essential for the extraction of pectin but soft, juicy fruits may
need little if any additional water. Firm fruits need only enough water to cover
(approximately one cup per pound or 250 milliliters per ½ kilogram). An excess should
be avoided because it dilutes the pectin and must be boiled away when the jelly is
made.

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A simmering temperature is sufficient to extract the pectin from fruit pulp. The cook-
ing time varies with the fruit and with its firmness. Soft fruits require 5 to 10 minutes.
Firm fruits like apples may need to be cooked 15 to 20 minutes. Long cooking should be
avoided because heating the pectin after it has been removed from the tissues
hydrolyzes (depolymerizes) it and lowers its jelly-making capacity. For fruits rich in
pectin a second extraction may be made. The first should be drained from the pulp, a
small amount of water added, and the pulp simmered a second time. Most of the color,
the acids, and the salts are removed by the first extraction. The second extraction may
yield almost as much pectin as the first, however. The yield of extract averages 1 to 1
1/3 cups per pound of fruit.

Clarification

The cooked fruit is first strained to separate pulp from extract. The latter is then
clarified by allowing it to drip through a jelly bag made of closely woven cloth or several
thickness of cheesecloth. Squeezing the pulp increases yield but tends to make the
extract cloudy.

Testing for Pectin

The sugar-carrying capacity of the extract should be tested, preferably with a
Jelmeter. Otherwise, ¾ cup sugar per cup of extract should be used. The yield of jelly
will be greater, the higher the proportion of sugar to fruit extract.

Boiling the Jelly

The extract should be combined with an amount of sugar appropriate for the jellying
power of the pectin before boiling begins. Sugar retards depolymerization of the pectin
as the mixture boils. Cooking lots should be kept small (two to four cups) and the
heating unit should be large enough and hot enough to maintain a full, rolling boil. Long,
slow evaporation hydrolyzes pectin and brings about extensive inversion of sucrose.

The capacity of the container should be four times the volume of the fruit extract to
allow for foaming of the jelly as it boils. The clarity of jelly compared to the fruit extract
from which it is made is due to material collecting in the foam.

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JOB SHEET # 2-1

Job Title : Mixing measured pectin, acid and sugar with the prepared
Purpose : Fruit Extract
To understand and perform the procedure for mixing
Conditions or Measured pectin, acid and sugar with the prepared fruit
Situations for the Job: extract

Equipment, Tools The sugar carrying capacity of the extract should be tested
With a jelmeter
And Materials :
Extracted juice, pectin, acid, sugar, food containers, stove,
Precautions : Pan and tray, Jelmeter
Fruits that are just ripe or slightly under ripe should be used.

PROCEDURE:

1. Your instructor will assign the product that you will process.
2. Using the extracted juice from your previous laboratory exercise, process it to

sugar concentrate products.
3. The extract should be combined with an amount of sugar appropriate for the

jellying power of the pectin before boiling begins.
4. Make sure that you follow the procedure in boiling the extract.
5. Your instructor will rate your overall performance for this module.
6. Prepare your Production Data Report.

Code No. Adjusting Acid, Pectin and Sugar and Cooking Date: Developed Date: Revised Page 29

Sugar Concentrate June 2005 December 2005

SELF-CHECK #2-1

______1. Instrument required to measure the hydrogen-ion concentration of a pectin
solution.

______2. Juice that is usually used to supplement the acidity of fruits lacking in
tartness.

______3. Instrument used to measure the viscosity of a pectin solution.

______4. The temperature sufficient to extract the pectin from pulp of fruits.

______5. Length of time for processing jelly in boiling water bath to prevent the
growth of certain molds.

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Sugar Concentrate June 2005 December 2005

ANSWER KEY #2-1

1. pH meter
2. Lemon
3. Jelmeter
4. Simmering
5. 5-6 minutes

Code No. Adjusting Acid, Pectin and Sugar and Cooking Date: Developed Date: Revised Page 31

Sugar Concentrate June 2005 December 2005

QUALIFICATION : FOOD PROCESSING NC III

UNIT OF COMPETENCY : Process Food by Sugar Concentration

MODULE : Adjusting Acid, Pectin and Sugar and Cooking Sugar

Concentrate

LEARNING OUTCOME #3 : Cook mixture to required consistency.

ASSESSMENT CRITERIA:
1. Desired end point is checked / tested.

RESOURCES:

Equipment and Facilities Tools and Instruments Supplies &Materials
Stove/Burner Refractometer
Candy Thermometer
Jelly Thermometer
Casserole
Wooden ladle
Measuring Spoon/Cup

References:

1. De Leon, S.Y. and Guzman M.P. 1998. Preservation of Philippine Foods, A
Manual of Principles and Procedures.

2. Gatchalian, M. M. and S. De Leon. 1992. Introduction to Food Technology
3. Gonzales, Olympia N., et. al. 1982. Philippine Handbook on Canned Low Acid

Foods. A project of NSDB-NIST and No. 7801. National Institute of Science and
Technology Authority.
4. Lopez, A. 1981. A Complete Course in Canning-Processing Procedures for
Canned Products. The Canning Trade. Baltimore Maryland, USA:
5. Preservation of Fruits and Vegetables.1983. Laboratory Services Division, Bureau
of Plant Industry.

Code No. Adjusting Acid, Pectin and Sugar and Cooking Date: Developed Date: Revised Page 32

Sugar Concentrate June 2005 December 2005

Learning Experiences
Learning Outcome #3: Cook mixture to required consistency.

LEARNING ACTIVITIES SPECIAL INSTRUCTIONS

1. Read Information Sheet # 3-1: Information Sheet # 3-1:
“ Assessing Doneness of Jelly “ “ Assessing Doneness of Jelly “

2. Read Information Sheet # 3-2: Information Sheet # 3-2: “Characteristics
“Characteristics of Different Fruits and of Different Fruits and Vegetables
Vegetables Preserve in Sugar” Preserve in Sugar”

3. Read Information Sheet # 3-3: Information Sheet # 3-3
“General Process/Quality Control Points: “General Process/Quality Control Points:

Fruit Preserves Fruit Preserves
Jam Jam
Marmalade Marmalade
Jellies Jellies
Fruit Paste or Pastilles Fruit Paste or Pastilles
Candied Fruits and Glazed Fruits Candied Fruits and Glazed Fruits
Fruit Drink Concentrate Fruit Drink Concentrate

4. Perform: Job Sheet # 3-1: Processing Products of

Job Sheet # 3-1: Processing Products of Sugar Concentration

Sugar Concentration

5. Perform Self Check # 3-1 Self Check # 3-1
Answer Key # 3-1
6. Check you answer using the answer
key # 3-1

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INFORMATION SHEET # 3-1
ASSESSING DONENESS OF JELLY

When jelly is made by the hot evaporation method, the boiling point of the mixture
may be used as one index to doneness. All fruit pectin extracts do not form the best
gels at the same sucrose concentration, however. Although most are done at a sugar
concentration represented by a boiling point range of 3° to 5°C (5° to 9°F) above the
boiling point of water (103° to 105°C or 217° to 221°F at sea level and with barometric
pressure at 760 mm of mercury), some should be boiled somewhat short of this
concentration and others may require a slightly higher concentration. The exact
concentration of sugar will depend upon the quantity and quality of the pectin and upon
the hydrogen-ion concentration of the mixture.

The following test may be used to determine whether the concentrations of pectin
and hydrogen ions are high enough to form a gel. The mixture should be removed from
the hot unit momentarily to avoid overcooking it while the test is being made.

A small amount of the hot syrup is rolled in the bowl of a metal spoon to cool it
slightly. The mixture is then allowed to drip off the edge of the spoon. Incipient gelation
thickens the mixture and causes heavy drops of liquid to coalesce and break or cut
away sharply as they leave the spoon in what is known as the sheet test (Figure). A
sheet test is an indication that all the variables that influence gel formation are at least
sufficiently concentrated. It is not a guarantee that the jelly has not been cooked beyond
the optimum stage, however. The ability to recognize the sheet test when it first appears
takes some experience; it is complicated by the fact that all fruit pectins do not sheet in
the same fashion. If a jelly fails to give a sheet test when it is boiled to 105°C (221°F),
addition of lemon juice is a way to rule out a deficiency of hydrogen ions as the cause. If
a mixture that is sufficiently tart still fails to gel when the boiling point reaches 106.9°C
(224°F), equivalent to a 70-percent sucrose solution, this indicates that too much sugar
was combined with the original extract for the jellying power of the pectin. Adding one
teaspoon of liquid pectin per cup of original fruit extract and boiling the mixture for 30
seconds to a minute may give a gel.

Figure The sheet test for the doneness of jelly.
(From Helen Charley, Food Study Manual. Copyright
© 1971 by the Ronald Press Company, New York, p.
253. Reprinted by permission.)

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KEEPING QUALITY OF PECTIN JELLY

The concentration of sugar in jelly boiled to 103° to 105°C (217° to 221°F) lowers the
vapor pressure of the water and the water activity, aw, sufficiently that the growth of
most microorganisms is limited. However, molds can grow on the surface of jelly that is
exposed to air. Traditionally, paraffin or a wax seal has been used to exclude air from
the surface of jelly and so inhibit mold growth. A break in the seal or a pocket of air
trapped underneath with mold spores may result in mold growth. Because of this and
because certain molds produce mycotoxins, processing jelly in ½ pint or 1-pint canning
jars with self-sealing lids in a boiling water bath is recommended. A processing time of
five minutes is recommended for altitudes up to 1,000 feet and an additional processing
time of one minute for each additional 1,000 feet of altitude.

Crystals in Jelly

Sucrose crystals may form in jellies “ Assessing Doneness of Jelly “boiled to a
high temperature and especially in those that lack tartness. Crystals are likely to form in
jellies made with pectin concentrate and a short boil, which gives little opportunity for
inversion of sucrose. Glasslike crystals of potassium acid tartrate are likely to form in
grape jelly. Chilling the grape pectin extract for 24 to 48 hours and decanting the liquid
above the sediment is recommended. Grape jelly made in small lots and used promptly
will be free of crystals, because they form slowly. Reducing the concentration of cream
of tartar by diluting grape pectin extract with that from other fruit, such as apple, is also
recommended to prevent crystal formation.

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INFORMATION SHEET #3-2

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INFORMATION SHEET #3-3

A. General Process/Quality Control Points Fruit Preserves

Problems/Causes/Solution
1.Shriveled and tough – use of a thick syrup at the start will draw out the juice of the
fruit very fast and will coat it instead of allowing the syrup to enter the tissue of the fruit;
cooking in high temperature and slow cooling.

Use thin syrup at the start and cool product immediately.
2.Serious injury to flavor and color of the finished product – cooking too large per
batch prolonged cooking at high temperature and slow cooling

Immediate cooling after processing is needed. Best to cook at 1-2 kg per batch,
should be stirred frequently when mixture begins to thicken to prevent scorching and
cook only to jellying point. Select sound fruit.
3. Crystallization of sugar – inappropriate amount of acid.

Use right amount of acid to prevent crystallization.
4. Loss of color – improper storage.

Store in a dark, dry, cool place.

B. General Process/Quality Control Points for Jam Making

Problems/Causes/Solution

1. Slack jam - is caused by prolonged boiling resulting to the hydrolysis of pectin which
produces watery syrup in the product; too low acidity impairs the setting properties of
pectin and frequently inhibits gel formation; mineral salts in fruits delay, and if present in
large quantities prevent setting entirely; general pectin deficiency of the fruit or fruit pulp
used; too much sugar in proportion to pectin and excessive cooking prior to filling cause
broken or improper setting.
2. Syneresis – (weeping or bleeding) is cause by too high acidity which breaks up the
gel network of jam; too little pectin; excess water and excess of invert sugar.

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3. Discoloration - is caused by: prolonged boiling resulting to the caramelization of
sugar or the breakdown of chlorophyll which turns from green to brown; insufficient
cooling after filling; discolored pulp as over ripening causes browning in a large variety
of fruit; excessive use of buffers; contamination with metals; and biological damage or
mechanical injury.

4. Crystallization - maybe due to high acidity which causes excessive inversion sugar
resulting in the granulation of dextrose; too low acidity which results in crystallization of
sucrose; prolonged boiling which causes excessive inversion; and excess cream of
tartar resulting in the formation of crystal tartars.

5. Hard or shrunken fruit - is caused by boiling of fruit with peel in heavy syrup with
insufficient pre-cooking. The peel skin becomes tough and the fruit pulp under the peel
is not able to absorb the sugar. It can also be caused by pre-cooking the fruit or peel in
very hard water. Calcium and magnesium salts in the water from pectates with pectin in
the fruit producing a tough texture.

6. Mold development and yeast - growth due to excessive humidity of the jam;
contamination prior to sealing of cans and jars; low soluble solids contents of the
product (recommended minimum is 65%; slack jam; and the use contaminated raw
materials)

C. General Process/Quality Control Points for Jellies

Problems/Causes/Solutions

1. Turbid Jelly – juice extract completely pressed.
Drain extract in a cloth bag or clarify the juice with pectin-breaking enzymes.

2. Failure in jelly formation – too much sugar in proportion to the pectin and acid of
the juice.

Determine the pectin and acid content before adjusting the sugar content of the
mixture.

3. Hydrolysis of pectin and formation of a syrupy caramelized mass – prolonged
boiling.

Rapid cooking prevents this defect.

4. Sugar crystals – concentration of finished product exceeds 70˚Bx.
Establish the exact end point of cooking and don’t exceed it.

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Sugar Concentrate June 2005 December 2005

D. General Process/Quality Control Points for Marmalade

Problems/Causes/Solution

1.Turbid Jelly – caused by cloudy juice produced when very fine fruit particles pressed
through the filter cloth.

Drain extract in a cloth bag.

2. Failure in jelly formation – too much sugar in proportion to the pectin and acid of
the juice.

Determine pectin and acid before adjusting sugar content of the mixture.

3. Hydrolysis of pectin and formation of a syrupy caramelized mass – prolonged
boiling.

Rapid cooking prevents this defect.

4. Sugar crystals – concentration of finished product exceeds 70˚Bx causing some of
the sugar to crystallize out of the mixture.

Exact cooking end point must be observed.

E. Process/Quality Control Points for Fruit Paste or Pastilles

Problems/Causes/Solution

1. Molding – poor handling, improper storage conditions, inappropriate packaging,
inadequate processing.

Good quality control measures prevent these and ensure good quality.

2. Sweating – undercooked, insufficient cooling, inappropriate packaging material.

3. Adoption of correct quality control condition
Hardening – inappropriate packaging material, improper storage condition.

Invert syrup prevents toughness and hardness.

4. Sugar crystallization – over cooking at high temperature.
Acidify syrup to prevent crystallization.

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F. Process/Quality Control Measures for Candied Fruits and Glazed Fruits

Problems/Causes/Solution

1. Deformed candied fruits – use of overripe fruits. Ripe fruits which has full flavor and
aroma is too soft and cannot withstand the repeated boiling in syrup.
2. Sugar crystallizes – fruits not well washed and over dried.

Rinse fruits after syruping before drying.
3. Molding – candied fruit is still high in moisture.

Proper drying of fruit should be observed.

G. General Process/Quality Control Points for Fruit Drink Concentrate

Problems/Causes/Solution

1. Color Fading – use of inappropriate food color not compatible with other ingredients.
Use FD & C color.
2. Ring formation & sedimentation – inappropriate stabilizer.

Right type and level of stabilizer should be used. The stabilizer must be evenly
dispersed to obtain a smooth consistency.

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Sugar Concentrate June 2005 December 2005

Job Sheet # 3-1

Job Title : Processing of Sugar Concentration

Purpose : To understand and perform the procedure for jellies, jams and

marmalades.

Conditions or

Situations for the Job : Fruits and vegetables should be fresh, mature and well-ripened

to achieve the characteristics flavor and color of the finished

product.

Equipment, Tools and

Materials : Extracted juice, water, peeler, chopping board, food containers,

stove, pan and tray.

Precautions : Do not overcook fruits and vegetables because long boiling
reduces the jellying strength of the pectin and gives a cloudy
juice which is difficult to filter.

PROCEDURE :

1. Your instructor will assign the product that you will process.

2. Using the extracted juice from your previous laboratory exercise, process it to
sugar concentrate products.

3. Make sure that you follow the product specifications/criteria.

4. Your instructor will rate your overall performance for this Module.

5. Prepare your Production Data Report

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Sugar Concentrate June 2005 December 2005

PRODUCTION DATA REPORT

Product __________________________
Date of Production __________________________
Source of Raw Materials __________________________
Description and Weight of Raw Materials __________________________
__________________________
Physico-chemical Characteristics: __________________________
pH __________________________
titrable acidity
soluble solids __________________________
__________________________
__________________________

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Sugar Concentrate June 2005 December 2005

SELF CHECK # 3-1

Filling the blank:

1. The exact concentration of sugar will depend upon the quantity and quality of the
pectin and upon the ______________________concentration of the mixture.

2. A _____________________is and indication that all the variables that influence
gel formation are at least sufficiently concentrated.

3. _____________________are likely to form in jellies made with pectin
concentrate and a short boil, which gives little opportunity for inversion of
sucrose.

4. _____________________ weeping or bleeding is cause by too high which
breaks up the gel network of jam, too little pectin, excess water and excess of
invert sugar.

5. ______________________ or shrunken fruit is caused by boiling of fruit with
peel in heavy syrup with insufficient pre-cooking.

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Sugar Concentrate June 2005 December 2005

ANSWER KEY # 3-1

1. hydrogen ion
2. sheet test
3. Crystals
4. Syneresis
5. Hard

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PERFORMANCE ASSESSMENT

Code No. Adjusting Acid, Pectin and Sugar and Cooking Date: Developed Date: Revised Page 45

Sugar Concentrate June 2005 December 2005

EVIDENCE PLAN

Sector: FOOD AND BEVERAGE SECTOR

Unit of Competency: PROCESS FOOD BY SUGAR CONCENTRATION

Module Title: Adjusting Acid, Pectin and Sugar and Cooking Sugar
Concentrate

Ways in which evidence will be Observation
collected: (tick the column) Questioning
Written test
The evidence must show that Demonstration
the candidate…. Presentation of Final
Product
Third Party Report
Portfolio

1. Measure the required
amount of pectin, sugar    
and acid.

2. Mix measured pectin,  
acid and sugar with the
prepared fruit pulp/juice
extract/pieces.

3. Cook mixture to 
required consistency.

Note: *Critical aspects of competency

Prepared by: Date: ______________

Instructor Date: ______________
Supervisor

Code No. Adjusting Acid, Pectin and Sugar and Cooking Date: Developed Date: Revised Page 46

Sugar Concentrate June 2005 December 2005

PERFORMANCE TEST

Learner’s Name Date: Test Attempt
1st 2nd 3rd
Competency: PROCESS FOOD BY SUGAR
CONCENTRATION

Directions: OVERALL EVALUATION

CALL YOUR Level

INSTRUCTOR, ask Achieved PERFORMANCE LEVELS

instructor to assess your 4 – Can perform this skill without supervision and with
initiative and adaptability to problem situations.

performance on the 3 – Can perform this skill satisfactorily without assistance or
supervision.
following critical task and

performance criteria below. 2 – Can perform this skill satisfactorily but requires some
assistance and/or supervision.
You will be rated based on
the overall evaluation on the 1 – Can perform parts of this skill satisfactorily, but requires
right side. considerable assistance and/or supervision.

Instructor will initial level achieved.

PERFORMANCE STANDARDS Yes No N/A

For acceptable achievement, all items should receive a “Yes” or

“N/A” response.

1. Required amount of pectin, sugar and citric acid are
measured according to approved specification.
 GMP in measuring is fully observed.
 International Standards (CODEX) properly
observed.

2. Analysis of required amount of pectin, sugar and acid for:
a. Jelly
b. Jam
c. Preserves
d. Marmalades
e. Butters and Conserves
f. Fruit Paste or Pastilles
g. Candied Fruits and Glazed Fruits
h. Fruit Drink Concentrate

3. Measured pectin, acid and sugar are mixed with chopped
fruit pulp/juice extract/pieces of fruits according to recipe of
sugar concentrate.

 Calculated the exact amounts that must be used for any
particular product.

4. Mixture is heated and boiled/cooked to required consistency
according to recipe.
5. Mixture is cooked to required consistency

Satisfactory Not Satisfactory
Date: Date:

Code No. Adjusting Acid, Pectin and Sugar and Cooking Date: Developed Date: Revised Page 47

Sugar Concentrate June 2005 December 2005

WRITTEN TEST

Trainee name:

Unit of competency: PROCESS FOOD BY SUGAR CONCENTRATION

Competency NC III
standards

Questions Satisfactory response

Yes No

1. What are the functions of ingredients in jelly
preservation?

2. What are the different methods to determined the
pectin content of fruits?

3. What is a Brix/Acid ratio?

4. The concentration of pectin in finished jelly usually
varies between what percent?

5. What is the effect on jelly too low ratio of sugar to
pectin?

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Sugar Concentrate June 2005 December 2005

OBSERVATION CHECKLIST

Candidate name:

Assessor name: PROCESS FOOD BY SUGAR CONCENTRATION
Unit of competency: Preparing Equipment, Tools and Utensils
Module Title:

Competency NC III
Standards:

Date of assessment:

Time of assessment:

Instructions for the assessor:
1. Observe the candidate
2. Describe the assessment activity and the date on which
it was undertaken.
3. Place a tick in the box to show that the candidate
completed each aspect of the activity to the standard
expected
4. Complete the feedback sections of the form

OBSERVATION

The candidate… Yes No N/A

1. Measured the required amount of pectin, sugar and acid.

2. Mixed measured pectin, acid and sugar with the prepared
fruit pulp/juice extract/pieces.

3. Cooked mixture to required consistency.
The candidate’s overall performance was:

Satisfactory Not Satisfactory

Code No. Adjusting Acid, Pectin and Sugar and Cooking Date: Developed Date: Revised Page 49

Sugar Concentrate June 2005 December 2005