Topics:
Animal Refresher, Dairy Science
Milk Sugar
Which is known as milk sugar?
- Lactose — Correct Answer
- Lactic acid
- Glucose
- Galactose
Explanation:
Correct Answer: Lactose
Lactose is known as milk sugar. It is a disaccharide composed of glucose + galactose linked by a β-1,4-glycosidic bond. It is the principal carbohydrate in milk and is found almost exclusively in milk and dairy products.
Key Properties of Lactose
- Present in milk as a true solution.
- Least variable component of milk.
- Average content: Cow milk 4.9%; Buffalo milk 5.2%; Camel milk 5.6% (highest).
- Responsible for the mild sweetness of milk.
- Along with chloride, it is primarily responsible for depressing the freezing point of milk below 0°C.
- During fermentation (e.g., dahi making), bacteria convert lactose → lactic acid (souring of milk).
Lactose Intolerance
Lactose intolerance is caused by deficiency of lactase enzyme in the small intestine, preventing hydrolysis of lactose. Undigested lactose passes to the large intestine where it is fermented by bacteria → gas, bloating, diarrhoea.
Why Other Options Are Wrong
- Lactic acid → product of lactose fermentation; not a sugar.
- Glucose & Galactose → monosaccharide components of lactose after hydrolysis; not called 'milk sugar' themselves.
📚 About this Topic — Animal Refresher
This multiple choice question is from Animal Refresher, Dairy Science. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Refresher to strengthen your preparation.
