1.1 Introduction
Milk is defined as a secretion of mammary gland of female animals. It is an exceptionally good source of protein which is of a high biological value in promoting the growth of children (Ihekoronye and Ngoddy, 2005). Milk is a product highly conducive to microbial growth, especially bacterial pathogens depending on the manipulations it is subjected to. Milk have its physical, chemical and biological properties easily altered by the actions of microorganisms. Dairy products or milk products are a type of food produced from or containing the milk of mammals, most commonly cattle, water buffaloes, goats, sheep, and camels. Dairy products include food items such as yogurt, cheese and butter. A facility that produces dairy products is known as a dairy or dairy factory.
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
Milk composition and microbial load are essential factors that must be considered in assessing quality of milks because these factors affect processing of milks and their nutritional quality and safety (Flint et al., 2020). Powdered milk supports growth of bacteria, including Staphylococcus (S.) aureus; Enterococcus, Micrococcus, Streptococcus, Bacillus and Clostridium spp. as well as several other microorganisms (Pal et al., 2016). Other common contaminants in milk and milk products include Escherichia (E.) coli and Lactobacillus spp. (Kivanc et al., 2019). Bacterial growth in milk media is enhanced under conditions such as adequate water activity, favorable pH and adequate temperature (Sadhu, 2018).
Milk can be described as a white liquid produced by the mammary gland of mammals. It is the primary source of nutrition for young mammals before they are able to digest other types of food. Milk is also described as a good of outstanding interest, which is designed by nature to be complete good for very young mammals (Fox and Cameron, 2000). Milk contains a wide variety of constituents and contains most of the food factors associated with bacterial nutrition. Milk as a single food is of high nutritional value and is associated with spoilage microorganisms. At the time milk leaves the udder of the healthy cow, it contains few bacteria these stem from milk ducts and cistern.
During the milking process, bacteria are usually added from various sources. In hand milking the sources are air the hair of the animal manure, the milkers equipment such as pails, feed and machine. However, the milking equipment may serve as an important source of contamination if it is not carefully cleaned and sanitized (Ihekoronye and Ngoddy, 2005).
After milk has been drawn it is rapidly cooled to 450C of prevent contaminants from multiplying. To eliminate pathogens from milk the process of pasteurization is applied. This involves application of heat below the boiling point (Fraizer and Westhoff, 2008). The main thrust of this work is, therefore to evaluate the microbial contents of raw material from a dairy farm.
Therefore, in Nigeria where the research was carried out, the activities that was conducted is to evaluate the microorganism of raw milk from a dairy farm.
1.3 Statement of Problems
Investigation revealed that in Nigeria dairy farmers count their losses from unprotected raw milk derived from their ranch farms. Studies have also have also shown that this raw milk form dairy farms are laddened with micro-organisms that end up spoiling the milk and causing diseases to man that drink them. Consequently many un Nigerians have lost their lives through drinking the infected raw milk. There is fear that if this is not checked many more lives will be lost. The main thrust of this work therefore is to evaluate and identify bacteria content of raw milk and proffer solutions to their ameliorations.
1.4 Aim and Objectives of Study
The aim of the study is to evaluate the microorganism of raw milk from a dairy farm. In achieving this aim, the following specific objectives were laid out as follows:
- To evaluate the micro-flora on raw milk.
- To identify micro-organisms that contaminate raw milk.
- To investigate the relationship between age and effects of drinking contaminated raw milk.
1.5 Research Questions
The study came up with research questions so as to be able to ascertain the above stated objectives. The specific research questions for the study are stated below as follows:
- What are the microorganisms that contaminate raw milk and their symptoms?
- What is the relationship between age and effects of drinking contaminated raw milk?
1.6 Significance of Study
The significance of the study, is that it will help the populace to know the actual microorganism that can contaminate the milk. It also helps to know the dangers of consumption of unboiled and unprocessed raw milk. It avails one of health hazards due to contamination with pathogenic bacteria such as E. coli, S. aureus and S. typhi. Lives lost through drinking contaminated raw milk would be reduced.
This study will be of immense benefit to other researchers who intend to know more on this study and can also be used by non-researchers to build more on their research work. This study contributes to knowledge and could serve as a guide for other study.
1.7 Scope of Study
The scope of the research is focused on the microbial evaluation of raw milk for dairy farms in Obinze, Nekede and Okigwe Fulani cattle Ranch farm in Imo State.
1.8 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Research material: availability of research material is a major setback to the scope of the study.
- Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
- Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection.