Certified Cheese Professional Practice Exam

Which enzymes are primarily found in rennet?

1. Lactase and Protease

2. Chymosin and Pepsin

3. Amylase and Lipase

4. Rennin and Trypsin

The correct answer is: Chymosin and Pepsin

The presence of chymosin and pepsin in rennet is significant because these enzymes play a critical role in the cheese-making process. Rennet is derived from the stomachs of ruminant animals and is essential for coagulating milk, which is the first step in cheese production. Chymosin, also known as rennin, is the primary enzyme responsible for curdling milk. It acts on casein, the main protein in milk, causing it to coagulate and form curds, while the remaining liquid is known as whey. Pepsin is another important enzyme in rennet, which aids in the further breakdown of proteins and contributes to the development of flavor as the cheese matures. This combination of enzymes is particularly effective for cheese production, differentiating it from other enzymes, such as amylase and lipase, which are involved in the digestion of carbohydrates and fats, respectively. Thus, recognizing the dual role of chymosin and pepsin in curd formation and flavor development underscores why this answer is the correct choice in the context of cheese-making.