Food microbiology is the study of the microorganisms that inhabit, create, or contaminate food, including the study of microorganisms causing food spoilage. Hence, food safety is a major focus of food microbiology. Harvested foods decompose from the moment they are harvested due to attacks from microorganisms such as bacteria, mould, fungi and yeast. Microbial activity on the food can observed in order to determine the quality through the microbial population on the food. In this practical, we observe how the bacteria can be responsible for the spoilage of food by using enumeration concept. The fresh scad fish was bought early in the morning of the practical day to ensure the freshness of the fish. When the fish was packed in a sealed plastic bag to prevent atmosphere contaminants and kept in the refrigerator before used. The fruit such as apple, grape, banana, guava and orange are placed at room temperature without proper storage until rotten to compare the bacteria growth activity between fresh food and spoilage food.
The nature of the growth conditions, including the composition, water content and pH of the medium used as well as the conditions such as temperature and pressure, determine which bacteria in a mixed population can grow. Since there is no universal set of conditions that permits the growth of all microorganisms, it is impossible to enumerate all microorganisms by viable plating. The composition of the nutrient usually includes reagents that resist the growth