Final answer:
The enzyme that must be inactivated in orange juice to prevent cloud loss is pectinase. Pectinase breaks down pectin and can cause the juice to clear, which is not desired in natural OJ products. Heat treatments such as pasteurization are commonly used to inactivate the enzyme.
Step-by-step explanation:
The enzyme in orange juice (OJ) that must be inactivated to prevent cloud loss is pectinase. Pectinase is the enzyme responsible for breaking down pectin, which is a structural polysaccharide found in plant cell walls. When pectinase breaks down pectin, it can cause the cloudy appearance in OJ to become clear, which is not desired in some juice products. Therefore, to maintain the natural cloudiness that consumers expect from fresh OJ, pectinase needs to be inactivated, usually through pasteurization or other heat treatments.
Enzymes such as pancreatic amylase and trypsin are involved in the digestion of carbohydrates and proteins respectively, as presented in questions 23 and 30. In comparison to question 20, caseinase is identified as an extracellular protease, which indicates that it breaks down proteins outside of the cell. Catalase, referred to in question 6, is an enzyme that breaks down hydrogen peroxide but is not related to the stability of orange juice. Finally, enzymes like oxidases and digestive enzymes such as amylase (mentioned in question 15 and reinforced in comparison to saliva's function) play crucial roles in metabolic processes and digestive functions.