Topics:
Animal Refresher, Dairy Science
Properties of Milk Lactose
Which is true about milk lactose?
- All the above — Correct Answer
- Least variable component of milk only
- Lactose is present in milk in the form of true solution only
- Average lactose content of cow & buffalo milk is 4.5% & 4.8% respectively only
Explanation:
Correct Answer: All the above
All three statements about milk lactose are correct:
- Least variable component of milk: Unlike fat (which varies enormously with breed, stage of lactation, time of milking), lactose content remains remarkably constant across conditions. This is because lactose synthesis in the mammary gland is tightly regulated — it is the primary osmotic regulator of milk volume.
- Present as true solution: Lactose molecules dissolve completely in the aqueous phase of milk at molecular level — they are not colloidal or emulsified.
- Average lactose content: Cow milk = 4.9% (≈ 4.5% is sometimes cited in older references but 4.9% is from composition table); Buffalo milk = 5.2% (≈ 4.8% older reference). The answer key accepts 4.5% & 4.8% as per the question's own options.
Why Lactose Controls Milk Volume
Lactose is the main osmotic agent in milk. Since milk is isotonic with blood plasma, the amount of lactose synthesized by the mammary gland determines how much water is drawn into milk. More lactose synthesis → more milk volume.
📚 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.
