Isolation And Characterization Of Micro-Organisms From Stored Pap (Ogi)
Micro-organisms present in stored pap (ogi) play a crucial role in its fermentation process, contributing to its flavor, texture, and nutritional profile. These microorganisms, including lactic acid bacteria such as Lactobacillus spp. and yeasts like Saccharomyces spp., initiate and sustain the fermentation of the maize or sorghum flour mixture, converting sugars into lactic acid and ethanol, respectively. This fermentation process not only enhances the taste and aroma of the pap but also promotes the production of beneficial compounds such as vitamins and organic acids. However, improper storage conditions or contamination can lead to the growth of undesirable microorganisms, potentially causing spoilage and compromising the quality and safety of the product. Therefore, understanding the microbial dynamics in stored pap is essential for ensuring product consistency and safety, highlighting the importance of proper storage practices and quality control measures in pap production.
The microbial changes which took place during the steeping and storage of pan (ogi) was studied. The steeped water had an initial PH of 6.8 which latter reduced to 4.9 at the end of steeping. The bacterial number for the steeped water ranged from 4.7×104 to 3.2 x 107 cfu/ml while the fungal number ranged from 1.5 x103 to 5.7 x 106 cfu/ml. In the stored pap, pap I had higher count which range from 7.2×104 to 6.0×107 cfu/g while 6.0×107 to 1.6×1011. The fungal count for pap I and II ranged from 8.2 x 105 to 2.5×1012 and 8.2×106 to 3.6×1010 respectively. The bacteria isolated from stee pingwere Lactabacillus species Bacillus specie, Corynebacterium, streptococcus specie and clostridium species. The fungi were Aspergillus species fusrarium specie, pencillium specie sachanomyces specie and candida specie. The bacteria spp isolated from stored pap were lactobacillus species, streptococcus specie Eubacterium specie, Pseudomonas specie, Baccillus specie, streptococcus specie, Lactobacillus specie, Leucomostoc specie for pap I and II respectively. The fungi isolated were Aspergillus specie, Pensillum specie, fusarium specie, sacharomyces specie, candida specie, Debaryomyces specie for pap I and II respectively. The pap stored without changing water developed an off flavour after 48 hours and is not fit for consumption. On the other hand, the pap stored while changing water is fit and better for consumption.
Title page
Certification
Dedication
Acknowledgement
Abstract
List of tables
List of figures
Table of contents
CHAPTER ONE
INTRODUCTION
1.1 Background of the study
1.2 Statement of problem
1.3 Aim and objectives of the study
1.4 Hypothesis
1.5 Justification of the study
1.6 Significance of study
1.7 Limitation of the study
CHAPTER TWO
LITERATURE
2.1 Origin of maize pad
2.2 Structure of maize grain
2.3 Chemical composition of maize grain
2.4 Uses of maize pap
2.5 Chemical changes in stored pap (ogi)
2.6 Nutrition changes in stored pap
2.7 Microorganisms associated with stored pap
CHAPTER THREE
MATERIALS AND METHOD
3.1 Collection of sample
3.2 Materials and equipments used
3.3 Media and reagents used
3.4 Preparation of pap (ogi)
3.5 Quantitative analysis of microorganisms
3.5.1 Serial dilution
3.5.2 Culturing technique
3.6 Isolation of bactria
3.7 Characterization of isolate
3.8 Biochemical test for identification of microorganisms
3.9 Identification of fungi
CHAPTER FOUR
RESULT AND DISCUSSION
CHAPTER FIVE
5.1 Conclusion
5.2 Recommendation
References
Appendix
INTRODUCTION
1.1 BACKGROUND OF THE STUDY
Cereals have been known to man from the earliest times porridge prepared from cereals are eaten in different parts o the world, especially in developing countries where they may present the basic diet. This porridge could be baked to enhance the taste, quality and improve digestibility (Oke 1967, Adeniyi and Potter 1978, Uno and field 1981).
Corn (zea mays) is one of cereals which is an important raw material in human diet. In Nigeria, maize is grown mainly in the southern part of Nigeria while sorghum (Sorghum bicolor) and millet (perinisetum typhoideum) are grown in the northern part of the country. A fermented cereal product is known as paplogi). Corn is processed into traditional food such as paplogi) Umo and fields 1981).
Pap is a fermented non-alcoholic starchy food and is a major staple food widely consumed in west Africa. It is a sour fine past beverage which when cooked produces a thin semi solid porridge. Pap (Ogi) porridge has a smooth texture and a sour taste resembling that of yoghurt,. In Nigeria, some states such as Anambra, Imo, Enugu and Abia refer to it as Akamu but Ogi is a Yoruba name but most state of Nigeria, it refers to maize pap. On the other hand, sorghum pap is known as Ogi baba while millet pap is known as Ogi gero in Yoruba (Banigi 1977, Onyekwere and Akinrele 1977).
Pap logi) can be consumed with variety of other product including with bread, steamed been cake (moi-moi), fried bean cake (Akara), fried yam and plantain etc. it is used as a main meal for adult and sick patients and it is suitable for breakfast, lunch and dinner. Pap is widely used as the first native food given to babies at wearing to supplement breast milk and is a major breakfast cereal for pre-school children and adults. It is consumed as a main meal for convalescing patients because it can easily be digested. As a wearing food, it is utilized mainly by low income earners category, it is estimated that about 25 million or more adults eat it about 4-5 days weakly (Banigo 1972). Milk and sugar may be added to improved the taske and nutritional quality. Pap is cooked and turned into a stiff gel called Agidi which is similar to kenkey, a fermented shanian product (Muller 1988, withby 1968). Some Yoruba indigens beliwved that pap is capable of stimulating the production of breast milk in Nursing mother (Bassir 1962). However, there has been no qualitative evidence of support of this belief.
In spite of it’s important in the Nigeria diet, pap manufacture is essential a home based industry. There are at present no large scale factory operation for the production of pap. The manufacture is carried out on a small scale by some house wives as a commercial venture in many parts of the country. The cleaned grain free of dirt and impurities steeped in eastern ware, plastic or enamel pot for 1-3 days at room temperature, this is followed by wet milling and sieving. Twenty-four (24) hours of sleeping leads to a greater depletion of the fermentable carbohydrate. After sieving, the coarse material obtained is wash with water to separate more of the starch. The filtered slurry is allowed to sediment and undergo further fermentation for 1-2 days at room temperature. The coarse matter which is separated is used ad animal feed while the sediment (Pap) is boiled to obtain.
1.2 STATEMENT OF PROBLEM
Microorganisms are involved in the processing of pap especially during fermentation and equally during storage. Few organisms are found in the pap, if it is properly stored. Their presence in pap during storage leads to irregular of flavour and loss of nutrients (van veen and steinkrans 1990). This is the result of their metabolic activity in the stored pap.
The tradiitonal method of pap production using various grains encourage significant nutrient losses, Losses m,ay occur during steeping, milling and sieving. Large parts of the protein in the grain is located in the testa and germ that are shifted off during processing.
Losses of fibre, protein, ash as well as some vitamins have been reported by Banigo and Muller (1972). Losses in nutrients could be minimized by using an improved wet milling method devised by Banigo and Muller (1972). At the end of this work, the microorganisms found in stored pap was isolated and characterized.
1.3 AIM AND OBJECTIVES OF THE STUDY
The aim of this study is to isolate and characterize micro-organisms from stored pap.
SPECIFIC OBJECTIVES ARE
i. To isolate and characterize bacterial contaminants from stored pap
ii. To isolate and characterize fungal contaminants from stored pap
1.4 HYPOTHESIS
HI: Bacteria and fungi are involved in the fermentation and storage of maize pap.
1.5 JUSTIFICATION OF THE STUDY
Not very much work has been done in this in recent times, with reference to the microbiology of the process. Some of the earliest workdone in this include those of Akiurele (1970-1977) and Barigo (1969, 1970, 1972, 1977).
1.6 SIGNIFICANCE OF STUDY
Pap stored improperly for a relatively length of time is likely to develop microorganisms. Therefore, the study is carried-out to identify this organisms and properly advice on the proper way of storing pap.
1.7 LIMITATION OF THE STUDY
This work is limited to viable microorganism present in the corn (zea mays) only which will be purchased from Ogbete in the Enugu Area.
Microorganisms can naturally colonize stored pap (Ogi), just as they can with any food product. Ogi, also known as pap, is a Nigerian fermented cereal pudding made from maize, sorghum, or millet. During the fermentation process and storage, various microorganisms can be present, including bacteria, yeasts, and molds. Some of the common microorganisms associated with the fermentation and storage of Ogi include:
- Lactic Acid Bacteria (LAB): LAB are the primary microorganisms responsible for the fermentation of Ogi. They convert sugars in the grains into lactic acid, which lowers the pH of the mixture, making it sour and creating a desirable texture. Lactobacillus species are often found in Ogi.
- Yeasts: Yeasts, such as Saccharomyces cerevisiae, can also play a role in the fermentation of Ogi. They produce ethanol and carbon dioxide during fermentation, contributing to the flavor and texture of the final product.
- Molds: Some molds can colonize stored grains and cereal-based products, including Ogi. While molds are generally not desirable, they can grow on Ogi if the product is not stored properly, leading to spoilage.
- Other Bacteria: Depending on the conditions and hygiene during preparation and storage, various other bacteria can also be present. Some of these bacteria may be undesirable and lead to spoilage or off-flavors if they proliferate.
To maintain the quality and safety of stored Ogi, it’s essential to store it in a cool, dry place and ensure proper hygiene during preparation and handling. The use of clean utensils and containers, as well as proper sealing to prevent contamination, can help minimize the growth of undesirable microorganisms. Additionally, traditional fermentation practices can help create an environment conducive to the growth of beneficial microorganisms while inhibiting the growth of harmful ones.