ABSTRACT
The present study was conducted to assess the microbial quality of powdered soymilk samples sold in Aba, Abia state. A total of 10 samples were randomly purchased from local markets within the metropolis. The study samples were differentiated into two categories, branded and unbranded powdered soymilk samples. The branded soymilk samples were labeled TE, BC, and UCD to reflect their brand names while the unbranded samples were labeled N1 to N4 .The total viable count of the soymilk samples ranged from 2.0×105-8.7×105 (cfu/g) with a branded powdered soymilk sample (TE2) giving the lowest count, while the highest count was recorded in an unbranded sample (N2). The Total coliform count ranged from 4.5×104-9.0×104 (cfu/g), with a branded sample (UCD2) giving the lowest count while the highest count was recorded in an unbranded powdered soymilk (N2). The total fungal count ranged from 1.1×104 in a branded sample (TE1) to 3.3×104 (cfu/g) in an unbranded sample (N1). The isolates were four (4) bacteria (Staphylococcus aureus, Bacillus spp., Streptococcus spp., and E. coli) and two moulds (Aspergillus spp. and Penicillium spp.). Bacillus spp. recorded the highest incidence (8) and percentage occurrence (80%) while Aspergillus spp. and E. coli recorded the least incidence (4) and percentage occurrence (40%). Comparing the general counts, the study suggested the need for implementing regulatory measures like good manufacturing and management practices, hygienic distribution and retail storage practices for ensuring microbiological safety of powdered soymilk offered for public consumption in Aba, since both the branded and unbranded powdered soy milk samples gave results above the acceptable limits.
TABLE OF CONTENTS
Title page i
Certification ii
Dedication iii
Acknowledgement iv
Table of Contents v
List of Tables x
List of Figures xi
Abstract xii
CHAPTER ONE
INTRODUCTION
1.1 INTRODUCTION 1
1.2 AIMS AND OBJECTIVES 3
CHAPTER TWO
LITERATURE REVIEW
2.1 SOYBEAN 4
2.1.1 ORIGIN OF SOYMILK 4
2.1.2 AGRONOMIC CHARACTERISTICS 4
2.1.3 COMPOSITION OF SOYBEAN 5
2.2 SOYMILK 7
2.2.1 DEFINITION OF SOYMILK 7
2.2.2 HISTORY OF SOYMILK 8
2.2.3 COMPOSITION OF SOY MILK 8
2.2.3.1 CHEMICAL COMPOSITION OF SOY MILK 8
2.2.3.2 PHYTOCHEMICALS IN SOY MILK 10
2.2.4 CLASSIFICATION OF SOY MILK 12
2.2.5 SOYMILK PREPARATION METHODS 12
2.2.6 NUTRIONAL VALUES OF SOY MILK 18
2.2.6.1 SOYMILK INTAKE AND HEART DISEASE 18
2.2.6.2 SOYMILK AND MENOPAUSE 19
2.2.6.3 SOYMILK INTAKE AND BONE HEALTH 20
2.2.6.4 SOYMILK INTAKE AND BREAST HEALTH 21
2.2.7 MAJOR CONCERNS ABOUT SOY SUPPLEMENTS AND HEALTH PRODUCTS
2.2.8 MICROORGANISMS ASSOCIATED WITH SPOILAGE OF MILK AND MILK PRODUCTS
2.2.8.1 PSYCHROTROPHS 22
2.2.8.2 COLIFORMS 23
2.2.8.3 LACTIC ACID BACTERIA 23
2.2.8.4 FUNGI 24
2.2.8.5 SPORE-FORMING BACTERIA 25
2.2.8.6 OTHER MICROOGANISMS 26
2.2.9 PRESERVATION AND STORAGE OF MILK AND PRODUCTS 26
CHAPTER THREE
MATERIALS AND METHODS
3.1 SOYMILK SAMPLES 28
3.2 STERILIZATION OF MATERIALS 28
3.3 MEDIA USED AND THEIR PREPARATION 28
3.4 MICROBIOLOGICALANALYSIS OF SAMPLES 29
3.4.1 SERIAL DILUTION 29
3.4.2 ISOLATION AND ENUMERATION 29
3.5 CHARACTERIZATION AND IDENTIFICATION OF THE BACTERIAL ISOLATES 30
3.5.1 PURIFICATION AND STORAGE OF THE ISOLATES 30
3.5.2 COLONIAL MORPHOLOGY 30
3.5.3 GRAM STAINING 30
3.5.4 BIOCHEMICAL TESTS 31
3.5.4.1 CATALASE TEST 31
3.5.4.2 COAGULASE TEST 32
3.5.4.3 INDOLE TEST 32
3.5.4.4 METHYL RED TEST 32
3.5.4.5 VOGES PROSKAUER TEST 33
3.5.4.6 CITRATE UTILIZATION TEST 33
3.5.4.7 OXIDASE TEST 34
3.5.4.8 SUGAR FERMENTATION TEST 34
3.6 IDENTIFICATION AND CHARACTERIZATION OF THE FUNGAL ISOLATES
CHAPTER FOUR
RESULTS 36
4.1 RESULTS 36
CHAPTER FIVE
DISCUSSION, CONCLUSION AND RECOMMENDATIONS
5.1 DISCUSSION 42
5.2 CONCLUSION 45
5.3 RECOMMENDATIONS 45
REFERENCE 47
CHIDINMA, 2 (2020). MICROBIAL QUALITY OF POWDERED SOY MILK SOLD IN ABA . Mouau.afribary.org: Retrieved Nov 24, 2024, from https://repository.mouau.edu.ng/work/view/microbial-quality-of-powdered-soy-milk-sold-in-aba
20476, CHIDINMA. "MICROBIAL QUALITY OF POWDERED SOY MILK SOLD IN ABA " Mouau.afribary.org. Mouau.afribary.org, 05 May. 2020, https://repository.mouau.edu.ng/work/view/microbial-quality-of-powdered-soy-milk-sold-in-aba. Accessed 24 Nov. 2024.
20476, CHIDINMA. "MICROBIAL QUALITY OF POWDERED SOY MILK SOLD IN ABA ". Mouau.afribary.org, Mouau.afribary.org, 05 May. 2020. Web. 24 Nov. 2024. < https://repository.mouau.edu.ng/work/view/microbial-quality-of-powdered-soy-milk-sold-in-aba >.
20476, CHIDINMA. "MICROBIAL QUALITY OF POWDERED SOY MILK SOLD IN ABA " Mouau.afribary.org (2020). Accessed 24 Nov. 2024. https://repository.mouau.edu.ng/work/view/microbial-quality-of-powdered-soy-milk-sold-in-aba