This set of Dairy Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Milk Reception”.
1. Tests for proper pasteurization are based on the activity of which enzyme?
Explanation: Phosphatase is an enzyme which is naturally present in milk, but is destroyed at a temperature just near to the pasteurization temperature. Alkaline Phosphatase test is used to indicate whether milk has been adequately pasteurised or whether it has been contaminated with raw milk after pasteurization.
2. Starch is split by which enzyme?
Explanation: Diastase is an enzyme group that is originally found in malt and it is produced when the germination of the seeds happens. Diastase converts starch into maltose and after that it converts it this into glucose.
3. What is the freezing point of milk?
a) 0 °C
b) -0.55 °C
c) -1 °C
d) -1.55 °C
Explanation: Milk that has been watered down contains more water and less solutes, so its freezing point is closer to 0 °C. Most milk processors will conclude that milk has been watered down if the freezing point is anywhere above -0.55 °C.
4. What is the average boiling point of milk?
a) 100-101 °C
b) 105-110 °C
c) 115-117 °C
d) 102-105 °C
Explanation: Milk is a mix of butter fat and water so it is slightly heavier than water. The boiling points of liquids are due to the gravity of the liquid. Milk boils at 100-101 °C.
5. What is the average specific gravity of normal whole milk at 16 °C?
Explanation: The specific gravity of milk measured at 15oC or 20oC is normally 1.028 – 1,033 kg/litre. The specific gravity depends on the protein and fat content. The specific gravity of fat is 0.93, solids-non-fat, 1.6 and water 1.0 kg/litre.
6. Which is the pre-dominating organism in dirty utensils of milk?
a) Lactobacillus bulgaricus
c) Streptococcus lactis
Explanation: Streptococcus lactis, Members of the Lactococcus genus (lactis, milk; milk cocci) are facultatively anaerobic, catalase-negative, gram-positive cocci that occur singly, in pairs, or in chains. They are extensively found in dirty milk utensils.
7. Energy value of a food is measured in terms of?
Explanation: Energy value calculation uses a single factor for each of the energy-yielding substrates (protein, fat, and carbohydrate), regardless of the food in which it is found. The energy values are 37 kJ/g (9.0 kcal/g) for fat, 17 kJ/g (4.0 kcal/g) for protein, and 17 kJ/g (4.0 kcal/g) for carbohydrates.
8. Legal butter must contain at least what percentage of fat?
a) 70 %
b) 80 %
c) 90 %
d) 95 %
Explanation: Butter must contain at least 80% butterfat. In practice, most American butters contain slightly more than that, averaging around 81% butterfat.
9. The high nutritive value of cheese is due to which of the following?
a) High mineral contents
b) High protein contents
c) Taste & flavor
Explanation: Cheese has been an important part of the human diet, both as a dietary staple and gourmet food. In addition to being delicious, it is highly nutritious and very rich in several vitamins and minerals.
10. Food value of ice cream depends to a large extent on its?
Explanation: The food value of a particular food measures of how good it is for you, based on its level of vitamins, minerals, or calories. Ice cream’s food value depends on its composition.
11. Chlorine compounds have widespread acceptance in the dairy industry due to?
b) High sanitizing efficiency
c) High corrosiveness
d) Oxidative properties
Explanation: Sanitization is one of the important aspects of the dairy industry. Chlorine is a highly efficient sanitizing agent.
12. At what concentration chlorine sanitizing solutions are usually used in the dairy industry?
a) 50-100 ppm
b) 100-200 ppm
c) 200-500 ppm
d) 500-800 ppm
Explanation: It is important to prepare the sanitizing solution accurately to ensure that the concentration is in optimum range for optimal results. Chlorine sanitizing solution to be effective is used at the concentration of 200-500 ppm.
13. The process of raising or lowering the percent of fat in milk or cream to the desired standard is called?
Explanation: Standardization of milk refers to the adjustment which means raising or lowering of fat and solids not fat levels of milk. It is simply the process of adjusting the fat content of milk.
14. A product consisting of a mixture of milk and cream which contains not less than 10.5% milk fat is called?
a) Concentrated Milk
b) Low Fat Milk
c) Half-and –Half
Explanation: Half and half is simplyhalf whole milk and half cream. Its butterfat content is usually 12.5%. but never less than 10.5%.
15. Buttermilk is a fluid product resulting from the manufacture of?
c) Ice cream
Explanation: Buttermilk refers to a number of dairy drinks. Originally, buttermilk was the liquid left behind after churning butter out of cream.
Sanfoundry Global Education & Learning Series – Dairy Engineering.
To practice all areas of Dairy Engineering, here is complete set of 1000+ Multiple Choice Questions and Answers.