Which cooking method causes fat soluble vitamins to diffuse out, vitamin B retained, vitamin C destroyed by heat?

• A. Vacuum packing
• B. Deep fat frying
• C. Boiling
• D. AFP/sterilisation

Answer: (B)

When foods are cooked in hot fat, a fat-based medium is present around the food. Fat-soluble vitamins (A, D, E, K) dissolve in that fat, so they diffuse out from the food into the frying oil, reducing their content in the food itself. Vitamin B vitamins are water-soluble, so with frying (where there’s little or no water contact) they’re largely retained in the food rather than leaching into the oil. Vitamin C is highly sensitive to heat, so the high temperatures used in deep fat frying destroy it. This combination—fat-soluble vitamins moving into the fat, B vitamins staying in the food, and vitamin C being degraded by heat—fits the scenario described.