effect of different marinades on quality characteristics of chevon jerky

127 Pages·2017·0.91 MB·English

EFFECT OF DIFFERENT MARINADES ON QUALITY
CHARACTERISTICS OF CHEVON JERKY

BY

GIFTY MOORE ARTHUR
(10507201)

THIS THESIS IS SUBMITTED TO THE UNIVERSITY OF GHANA, LEGON
IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE AWARD
OF MASTER OF PHILOSOPHY DEGREE IN ANIMAL SCIENCE

JULY, 2017
DECLARATION
I hereby declare that this thesis which is submitted to the Department of Animal
Science, College of Basic Applied Sciences, University of Ghana, for the award of
Master of Philosophy in Animal Science degree is the result of my own investigation.
This thesis has not been submitted or presented for another degree elsewhere, either in
part or in whole, except for other people‘s work which was duly cited and
acknowledged.

STUDENT
NAME: GIFTY MOORE ARTHUR
SIGNATURE:………………………………
DATE:………………………………………

SUPERVISOR CO - SUPERVISOR
NAME: DR. S. OHENE – ADJEI PROF ANNA. R. BARNES
SIGNATURE:………………………… ………………………………
DATE:…………………………………… ………………………………

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DEDICATION
This work is dedicated to my son Jethro Nana Eduah Ansah,my husband Raymond
Ansah, my parents Mr. George Edward Moore Arthur and Madam Bernice Eshun, my
siblings James Moore Arthur, Mrs. Constance Irene Cofie and Mrs. Patience Bernette
and lastly to my niece Princess Lisa Cofie.

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ACKNOWLEDGEMENTS
I am very grateful to the Almighty God, the creator and designer for the wisdom and
knowledge he has bestowed on me. Dr. S. Ohene - Adjei my supervisor also deserves
special commendation for his priceless dedication and support geared towards this
dissertation. I also wish to thank Prof. A. R. Barnes my co- supervisor, for the advice
and proof reading. My profound gratitude goes to Dr. Patrick Arthur of the
Department of Biochemistry for his support and advice. I will also wish to thank Dr.
Raphael A. Ayizanga for his support, advice and encouragement. I will also like to
acknowledge the entire staff of the Faculty of Agriculture, College of Basic and
Applied Science, especially those in the Animal Science Department for their support,
encouragement and guidance.

Finally, I will like to acknowledge Akua Kumi Yeboah, Mrs. Sarah Afia Addo,
Madam Rebecca Otoo and Madam Esther Akomaning, Alex Addo, Gifty Ziema
Bumbie, my fellow graduate students and my sensory panelists for the diverse ways in
which they contributed to the success of this dissertation. It is my prayer that all your
heart desires will be accomplished by God and he will crown all your effort with
success.

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TABLE OF CONTENTS
Declaration ................................................................................................................. i
Acknowledgements .................................................................................................. iii
Table of contents ...................................................................................................... iv
List of tables ............................................................................................................. ix
List of figures ............................................................................................................ x
Abstract .................................................................................................................... xi
CHAPTER ONE........................................................................................................ 1
1.0 Introduction ................................................................................................. 1
1.1 Problem Statement ...................................................................................... 4
1.2 Objectives ................................................................................................... 5
1.3 Justification ................................................................................................. 5
1.4 Hypothesis .................................................................................................. 6
CHAPTER TWO ....................................................................................................... 7
2.0 Literature Review ........................................................................................ 7
2.1 History of Jerky ........................................................................................... 7
2.2 Manufacturing Process ................................................................................ 8
2.3 Marinade ..................................................................................................... 9
2.3.1 Functionality of Marinades ................................................................. 10
2.4 Acidic Marinades ...................................................................................... 11
2.4.1 Tenderisation Action of Acidic Marinades in Meat ............................. 11
2.4.2 Antimicrobial Effect of Acidic Marinades .......................................... 13
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2.5 Enzymatic Marinades (Exogenous Proteolytic Enzymes) ........................... 15
2.6 Papain .................................................................................................... 18
2.6.1 Myofibrillar and Connective Tissue Degradation by Papain................ 19
2.7 Marinating Techniques and Duration ......................................................... 20
2.7.1 Marinating Methods ........................................................................... 20
2.7.2 Immersion .......................................................................................... 20
2.7.3 Multi-needle Injection Marinating ...................................................... 21
2.7.4 Vacuum or Manual Tumbling ............................................................. 22
2.8 Marinade Ingredient Functionality ............................................................. 23
2.8.1 Spices ................................................................................................. 23
2.8.2 Salt (sodium chloride) ........................................................................ 24
2.8.3 Soy Sauce ........................................................................................... 25
2.8.4. Sweeteners ......................................................................................... 26
2.9 Preservation of Meat.................................................................................. 27
2.9.1 Odka .................................................................................................. 29
2.9.2 Qwanta ............................................................................................... 29
2.9.3 Biltong ............................................................................................... 29
2.9.4 Kilishi ................................................................................................ 30
2.10 Drying of Meat .......................................................................................... 30
2.10.1 Methods of Drying Meat .................................................................... 31
2.10.2 Natural or Traditional Drying Method ................................................ 32
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2.10.3 Sun Drying ......................................................................................... 32
2.10.4 Solar Drying ....................................................................................... 32
2.11 Artificial Heat Source ................................................................................ 33
2.11.1 Smoke House Drying ...................................................................... 33
2.11.2 Oven Drying ................................................................................... 34
2.11.3 Freeze Drying ................................................................................. 34
2.12 Rehydration Rate ....................................................................................... 36
2.13 Microbiology of Meat and Meat Products .................................................. 36
2.14 Food Safety Concerns of Jerky .................................................................. 37
2.15 Principles of Preservation of Shelf-Stable Dried Meat Products ................. 39
2.16 Shelf-Stability and Hurdle Effect ............................................................... 40
2.17 Packaging .................................................................................................. 42
2.18 Eating Qualities of Meat ............................................................................ 44
CHAPTER THREE ................................................................................................. 50
3.0 Materials and Methods .............................................................................. 50
3.1 Experimental Design ................................................................................. 50
3.2 Sample Preparation .................................................................................... 50
3.2.1 Treatments ......................................................................................... 51
3.2.2. Marination .......................................................................................... 51
3.2.3 Drying ................................................................................................ 51
3.3 Measurement ............................................................................................. 52
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3.3.1 pH Measurement ................................................................................ 52
3.3.2 Sensory Evaluation ............................................................................. 52
3.3.3. Rehydration Ratio .............................................................................. 53
3.3.4 Microbiological Analysis .................................................................... 54
3.4 Statistical Analysis .................................................................................... 55
CHAPTER FOUR ................................................................................................... 56
4.0. Results ...................................................................................................... 56
4.1 Sensory Evaluation .................................................................................... 56
4.1.1 Effect of Treatments on Chevon Jerky Tenderness ............................. 56
4.1.2 Effect of Treatments on Chevon Jerky Chewiness .............................. 59
4.1.3 Effect of Treatments on Chevon Jerky Juiciness ................................. 61
4.1.4 Effect of Treatments on Chevon Jerky Flavour ................................... 63
4.1.5 Effect of Treatment on Chevon Jerky Acceptability ............................ 65
4.2 Microbiological Evaluation ....................................................................... 67
4.2.1 Effect of Treatment on Total Plate Count............................................ 68
4.2.2 Effect of Treatment on E.coli .............................................................. 69
4.2.3 Effect of Treatment on Staphylococcus aureus ................................... 69
4.2.4 Effect of Treatment on Yeast and mould ............................................. 70
4.3 Moisture content (%) ................................................................................. 71
4.4 Rehydration Characteristics ....................................................................... 73

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CHAPTER FIVE ..................................................................................................... 75
5.0 Discussion ................................................................................................. 75
5.1 Sensory Evaluations .................................................................................. 75
5.2 Microbiological Evaluation ....................................................................... 79
5.3 Moisture Content (%) (Drying curve) ........................................................ 82
5.4 Rehydration Rate ....................................................................................... 85
CHAPTER SIX ....................................................................................................... 87
6.0 Summary, Conclusions and Recommendations .......................................... 87
6.1 Summary ................................................................................................... 87
6.2 Conclusions ............................................................................................... 90
6.3 Recommendations ..................................................................................... 90
References ............................................................................................................... 91

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LIST OF TABLES
Table 1: Enzymes Classified as ―Generally Recognised As Safe‖ (GRAS) for Meat
Tenderisation ........................................................................................................... 18
Table 2: Treatments of chevon jerky with papain and vinegar at various concentration
levels ....................................................................................................................... 51
Table 3: Frequency (%) of panelist‘s response on tenderness scale of chevon jerky . 57
Table 4: Frequency (%) of panelist‘s response on the effect of storage period on
tenderness of chevon jerky ....................................................................................... 58
Table 5: Frequency (%) of panelist‘s response on chewiness scale of chevon jerky .. 59
Table 6: Frequency (%) of panelist‘s response on the effect of storage period on
chewiness of chevon jerky ....................................................................................... 60
Table 7: Frequency (%) of panelist‘s response on juiciness scale of chevon jerky .... 61
Table 8: Frequency (%) of panelist‘s response on the effect of storage period on
juiciness of chevon jerky ......................................................................................... 62
Table 9: Frequency (%) of panelist‘s response on flavour scale of chevon jerky ...... 63
Table 10: Frequency (%) of panelist‘s response on the effect of storage period on
flavour of chevon jerky ............................................................................................ 64
Table 11: Frequency (%) of panelist‘s response on acceptability scale of chevon jerky
................................................................................................................................ 65
Table 12: Frequency (%) of panelist‘s response on the effect of storage period on
acceptability of chevon jerky ................................................................................... 66
Table 13: Effect of treatments on microbial count (log CFU/g meat sample) of
vacuum packaged chevon jerky stored for 30d ......................................................... 67
Table 14: Effect of storage time on microbial count (log CFU/g meat sample) of
vacuum packaged chevon jerky stored for 30d ......................................................... 68
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