Title Page
Contents
Abstract 9
Introduction 11
Materials and Methods 15
1. Preparation of pet jerky and storage condition 15
2. Analysis of physiochemical properties 16
2.1. Microbiological analysis 21
2.2. Biochemical analysis 22
3. Sensory evaluation 25
Results 26
1. Monitoring of microbiological changes in pet jerky during storage periods 26
2. Monitoring of physiochemical changes in pet jerky during storage periods 28
2.1. Changes of volatile basic nitrogen in pet jerky during storage periods 28
2.2. Changes of acid value in pet jerky during storage periods 32
2.3. Changes of moisture content in pet jerky during storage periods 36
2.4. Sensory Evaluation 45
Discussion 49
Conclusion 54
References 56
Table 1. Ingredient compositions and sizes of pet jerky of sample A and sample B using... 17
Table 2. Ingredient compositions and size of pet jerky of sample C using sea eel 18
Table 3. Ingredient compositions and size of pet jerky of sample D using a by-product of... 19
Table 4. Ingredient compositions and size for pet jerky of sample E using a by-product of... 20
Table 5. Changes of total viable cell counts in pet jerky samples during six months... 27
Table 6. Changes of volatile basic nitrogen value in pet jerky of sample A, B, C, D and E... 29
Table 7. Changes of volatile basic nitrogen value in pet jerky of sample A, B, C, D and E... 30
Table 8. Changes of volatile basic nitrogen value in pet jerky of sample A, B, C, D and E... 31
Table 9. Changes of acid value in pet jerky of sample A, B, C, D and E during six months... 33
Table 10. Changes of acid value in pet jerky of sample A, B, C, D and E during six... 34
Table 11. Changes of acid value in pet jerky of sample A, B, C, D and E during six... 35
Table 12. Changes of moisture content in pet jerky of sample A, B, C, D and E during six... 37
Table 13. Changes of moisture content in pet jerky of sample A, B, C, D and E during six... 38
Table 14. Changes of moisture content in pet jerky of sample A, B, C, D and E during six... 39
Table 15. Changes of brightness (L) value, redness (a) value and yellowness (b) value in... 46
Table 16. Changes of brightness (L) value, redness (a) value yellowness and (b) value in... 47
Table 17. Changes of brightness (L) value, redness (a) value yellowness and (b) value in... 48
Fig.1. Changes of moisture content in pet jerky of sample A during six months storage... 40
Fig.2. Changes of moisture content in pet jerky of sample B during six months storage... 41
Fig.3. Changes of moisture content in pet jerky of sample C during six months storage... 42
Fig.4. Changes of moisture content in pet jerky of sample D during six months storage... 43
Fig.5. Changes of moisture content in pet jerky of sample E during six months storage... 44