Step 1: Understanding the Concept:
The question asks to identify which of the listed conditions are considered defects in the quality of ice cream. Ice cream quality is judged on its flavor, body and texture, and melting characteristics.
Step 2: Detailed Explanation:
Let's evaluate each statement:
A. Rancid flavour: This is a serious flavor defect caused by the breakdown of milk fat by the lipase enzyme. It is highly undesirable.
B. Soggy body: This is a body and texture defect where the ice cream is heavy, dense, and wet, often due to low overrun or high solids. It is undesirable.
C. Fluffy texture: This is a texture defect caused by excessively high overrun (too much air), making the ice cream lack substance and feel like foam. It is undesirable.
D. Foamy meltdown quality: When ice cream melts, it should produce a smooth liquid. A meltdown that is foamy, frothy, or curdy indicates an unstable emulsion or other formulation issues. It is a defect.
All four listed items are well-recognized defects in ice cream evaluation.
Step 3: Final Answer:
Since A, B, C, and D are all considered defects in ice cream, the correct option is (D).