Characterization And Starter Culture Potentials Of Lactic Acid Bacteria Associated With The Fermentation Of Combined Grains Sorghum Bicolor And Pennisetum Glaucum Used For Kunu Zaki Production

ABSTRACT 

The study aimed at the Characterization and starter culture potentials of lactic acid bacteria during the fermentation of Sorghum biocolor and pennisetum glaucum for kunu-zaki, to determine the physicochemical properties of kunu-zaki, to enumerate microorganisms associated with kunu-zaki and isolate and characterize lactic acid bacteria from kunu zaki and to determine physiochemical properties of kunu-zaki and to isolate other microorganisms associated with kunu-zaki production. The media used was De Man Rogosa and Sharpe (MRS) Agar in culturing lactic acid bacteria, manufacturer description 67.1g into 1000ml of distilled water. Nutrient Agar in culturing bacteria, manufacturer description 28g into 1000ml of distilled water, MacConkey Agar in culturing coliform, manufacturer description 47g into 1000ml of distilled water, malt extract Agar in culturing yeast, manufacturer description 50g into 1000ml of distilled water (de Man 1960). Starter cultures are added to the raw materials in large numbers and incubated under optimal conditions. In common controlled-fermented products such as Sauer kraut and yoghurt. Lactic acid is produced by the starter culture bacteria to prevent the growth of undesirable microorganisms in non-sterile raw materials and these culture bacteria helps to make the products shelf-stable. These starter culture bacteria derived in the course of these study were Lactobacillus casei, Lactobacillus brevis, Lactobacillus fermentum, Lactobacillus plantarum etc. They help in the fermentation process of kunu-zaki.

TABLE OF CONTENTS 

Title page ﾿ i

Certification ﾿ ii

Dedication ﾿ iii

Acknowledgments ﾿ iv

Table of contents ﾿ v

List of tables ﾿ vi

List of figures ﾿ vii

Abstract ﾿ viii

CHAPTER ONE: 

1.1 ﾿ Introduction ﾿ 1

1.2 ﾿ Aim and Objective of the Study ﾿ 2

1.2.1 Aim ﾿ 2

1.2.2 Objectives ﾿ 3

CHAPTER TWO: ﾿ LITERATURE REVIEW

2.1 ﾿ Fermentation of Cereal based Foods ﾿ 4

2.2. Some beneficial attributes of African fermented cereal-based foods ﾿ 9

2.2.1. Shelf-life extension and improved nutritional and sensory properties ﾿ 10

2.2.2. Inhibition of pathogenic microorganisms in fermented foods. ﾿ 10

2.2.3. Production of bacteriocins by lactic acid bacteria ﾿ 12

2.2.4. ﾿ Toxic, antinutritional and indigestible compounds incereal foods ﾿ 13

CHAPTER THREE

3.1 Sample Collection ﾿ 18

3.2 ﾿ Glasswares and Media Used ﾿ 18

3.3 Determination of Ph ﾿ 19

3.4 Microbiological analysis ﾿ 19

3.4.1 Enumeration of total bacteria ﾿ 19

3.4.2 Enumeration of total coliform ﾿ 20

3.4.3 Enumeration of Yeasts ﾿ 20

3.4.4 ﾿ Enumeration of lactic acid bacteria ﾿ 20

3.4.5 ﾿ Isolation of Lactic Acid Bacteria ﾿ 21

3.4.6 Characterization of lactic acid bacteria ﾿ 21

3.4.6.1 Morphological characterization ﾿ 21

3.4.6.2 Biochemical Characterization ﾿ 22

3.4.6.3 Physiological characterization ﾿ 23

3.4.7 Identification of lactic acid bacteria ﾿ 24

3.5 ﾿ Safety Properties of LAB ﾿ 24

3.5.1 ﾿ Haemolysis Test ﾿ 24

3.5.2 ﾿ Antibiotic Resistance Pattern ﾿ 25

3.6 ﾿ Rate of Acid Production ﾿ 25

CHAPTER 4

4.1 ﾿ RESULT ﾿ 26

CHAPTER 5

5.1 ﾿ Discussion ﾿ 33

5.2 ﾿ Conclusion ﾿ 35

5.3 ﾿ Recommendation ﾿ 35

REFERENCES ﾿ 36