Certified Cheese Professional Practice Exam

Which of the following is not a source of milk lipases?

1. Native milk

2. Added bacteria for fermentation

3. Somatic cells present in the milk

4. Animal feed additives

The correct answer is: Animal feed additives

The correct answer is based on the role of milk lipases and their sources. Milk lipases are enzymes that catalyze the hydrolysis of milk fats into free fatty acids and glycerol, and they can originate from various sources. Native milk contains naturally occurring milk lipases that are produced by the mammary glands of dairy animals. This is a vital enzyme for the development of flavor in fermented dairy products and can impact the shelf life and quality of milk. Bacteria added for fermentation, particularly lactic acid bacteria, can also produce lipases during the fermentation process. This enzymatic activity helps to develop flavors and textures in cheese and other dairy products. Somatic cells, which include white blood cells, are present in milk and can produce lipases as a response to infection or inflammation in the udder. The presence of these cells can indicate the health status of the dairy animal and can contribute to the lipolytic activity in milk. In contrast, animal feed additives are substances added to livestock feed to enhance growth, health, or milk production. While they may influence the overall health and productivity of dairy animals, they do not directly contribute to the presence of lipases in milk. Therefore, they are not a source of milk lipases.