Post on 22-Aug-2014
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Development of a Cheddar Cheese Using Biological Preservatives as Substitute for
Chemical Preservatives
C.P. Ulpathakumbura
AG/2008/2009/148
Department of Animal and Food Sciences
Faculty of Agriculture
Rajarata University of Sri Lanka
Introduction
• Milk is the most natural and nutritious, single food
on the earth
• Cows’ milk use for make several types of foods
• Cheese is a preserved form of milk made by using
live cultures to transform the milk through chemical
process, and then by the coagulation
Problem and Justification
• Cheese have high nutritional value• Preservatives use for the prevent the spoilage
Preservatives
Chemical Biological
• By using chemical preservatives
• Can use biological preservatives
Nisin Lysozyme
Lactic Acid Bacteria
Objectives
• General Objective
– Development of a Cheddar cheese using biological
Preservatives as substitute for chemical preservatives
Preservatives
• Specific Objectives
– To evaluate sensory properties of the cheddar cheese
– To assess the microbial properties of cheddar cheese
– To evaluate the physico-chemical properties of the cheddar cheese
Methodology
Step 1 • Preliminary studies
Step 2 • Cheese making process
Step 3 • Analysis of samples
Raw milk Cooling milkPasteurizationStandardization
Add preservatives
Add CaCl2Starter
inoculationAdd rennet
Incubation Remove wheyHeat/Cooking 1Cut curd
Milling Heat/ Cooking 2Remove wheyPressing
Salting Cheddar cheese
Waxing & StoringMolding
Cheddar Cheese Making Process
Preliminary StudiesStudy 01 - Select optimum time for the incubation
• pH were measured in each samples
Treatment Temperature Time
T1 32°C 30 minutes
T2 32°C 45 minutes
T3 32°C 60 minutes
T4 32°C 75 minutes
• Study 02 - Select the optimum level of Rennet
• Flavor was checked in each sample during storage
Treatment Amount Time
T1 0.05% 30 minutes
T2 0.04% 30 minutes
T3 0.06% 30 minutes
Study 03 - Select the optimum temperature for cooking
• Flavor and odor were checked in each sample during storage
Treatment Temperature Time
T1 32°C 40 minutes
T2 35°C 40 minutes
T3 38°C 40 minutes
• Selection of the best sample made by using different preservatives
Treatment Preservative
T1 - T2 Lysozyme
T3 NaNO3
T4 Lactic Acid Bacteria (LAB)
T5 Nisin
• Sensory Evaluation
– Used 35 untrained panelists
– Ranking test (5-like very much to 1-dislike very
much)
– Color, Flavor, Texture, Odor and Overall acceptability
• Analysis of Cheese Samples
A. Physico-chemical analysisB. Microbial analysisC. Proximity analysisD. Sensory evaluation
Week 0
Week 1
Week 2
Week 3
Week 4• A
• B• A• B
• A• B• D
• A• B
• A• B• C
1. Physico-chemical Analysis
• Dry matter percentage (DM %) - Oven dry method
• Moisture percentage (M %) - (100 – DM%)
• Texture - Instron machine
• pH - pH meter
• Titratable acidity - Titrating with NaOH
2. Proximate analysis
• Fat content - Gerber method
• Protein content - Kjeldhal method
• Ash content - Ignition in Muffle
furnace
3. Microbial Analysis
• Yeast and Mold count - PDA
• Total lactic acid bacteria count - MRS agar
• Coliform count - Violet red bile agar
Data Analysis
• Parametric data analysis– ANOVA for significance under α=0.05 level using SAS
• Data from sensory analysis– Friedman non – parametric test using Minitab
• Data from microbial analysis– Compare with Sri Lankan Standards (SLS 773-1987)
• Study 01 - Select optimum time for the incubation
– 45 min in 32°C incubated sample (T2) was given
optimum pH (5.6-5.9)Treatment pH
T1 6.4
T2 5.8
T3 5.1
T4 4.7
Results and Discussion
• Study 02 - Select the optimum level of rennet
– 0.05% and 0.06% had bitter taste (1 week storage)
– 0.04 % able to obtain a fine textured cheese without
bitter taste
0.06 % 0.04 % 0.05 %
• Study 03 - Select the optimum temperature for cooking
– T3 sample (38°C in 40 min) was better than other
– No bitter taste and off odor during storage
• Sensory Evaluation
– The best sample is nisin incorporated sample
– There was a significant difference in all attributes except in colour
Colour
Flavour
OdorTexture
Overall acceptability
0
5
Control
Lysozyme
NaNO3
Lactic acid bacteria
Nisin
• Physico-chemical Analysis• Titratable acidity variation of samples
0 1 2 3 41.00
1.50
2.00
2.50
3.00
3.50
Control LysozymeNaNO3LABNisin
Weeks
Titr
atab
le a
cidi
ty
• pH variation of samples
0 1 2 3 44.00
4.50
5.00
5.50
6.00
6.50
7.00
Control LysozymeNaNO3LABNisin
Weeks
pH
• Texture variation of samples
0 1 2 3 40.020
0.021
0.022
0.023
0.024
0.025
0.026
0.027
0.028
0.029
Control LysozymeNaNO3LABNisin
Weeks
Text
ure
(N)
• Dry matter content variation of samples
0 1 2 3 450.00
55.00
60.00
65.00
70.00
75.00
80.00
Control LysozymeNaNO3LABNisin
Weeks
Dry
matt
er %
• Moisture content variation of sample
0 1 2 3 420.00
25.00
30.00
35.00
40.00
45.00
50.00
Control LysozymeNaNO3LABNisin
Weeks
Moi
stur
e %
• Proximate Analysis• Fat content
10.00
10.50
11.00
11.50
12.00
12.50
13.00
13.50
a
a
a
a
a
Fat %
Cheese Samples
Fat %
• Protein content
8.25
8.3
8.35
8.4
8.45
8.5
8.55
8.6
a a
aa
a
Avg
Cheese Samples
Proti
en %
• Ash content
9.20
9.40
9.60
9.80
10.00
10.20
10.40
10.60
10.80
11.00
11.20
a
a
a
a a
Series1
Cheese Samples
Ash%
• Microbial Analysis• Yeast and Mold count
0 1 2 3 40
200
400
600
800
1000
1200
1400
Control LysozymeNaNO3LABNisin
Weeks
cfu/
g
• Total lactic acid bacteria count
• Coliform count were zero during storage
0 1 2 3 47.90
8.00
8.10
8.20
8.30
8.40
8.50
8.60
8.70
Control Nisin
Weeks
Log
cfu/
g
Conclusion
• Biological preservative can be used to
preserve the Cheddar cheese effectively
without affecting the sensory qualities
• Nisin is the best biological preservative
among the tested preservatives
Suggestions
• Use biological preservatives as a blend and
evaluate the preservative ability
• Incorporation of starter culture with probiotic
microorganisms may bring additional benefits
and preservative ability
Thank you
Cost Benefit AnalysisPreservative g per 100l of milk Price for kg
Nisin 0.5 Rs. 18000
Lysozyme 2.5 Rs. 22000
NaNO3 1.5 Rs. 8500
LAB 5 Rs. 42000
1l 40g – 50g