Question

Aeromonas hydrophila growth in butter causes ______.

• A. Maltiness
• B. Barny flavour
• C. Fishiness
• D. Flat flavour

Hint:

Psychrotrophic bacteria like *Aeromonas* and *Pseudomonas* are major culprits of lipolytic spoilage in refrigerated butter, frequently resulting in fishy or rancid off-flavors.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Bacterial spoilage in dairy products like butter is often accompanied by distinct off-flavors resulting from the breakdown of milk proteins and lipids.

Step 2: Detailed Explanation:
*Aeromonas hydrophila* is a psychrotrophic, Gram-negative, rod-shaped bacterium capable of growing at refrigeration temperatures.
When it contaminates butter, its extracellular lipolytic and proteolytic enzymes break down fats and proteins.
This enzymatic degradation produces volatile compounds, specifically amines and certain free fatty acids, that impart a highly undesirable fishy off-flavor (fishiness) to the butter.
Maltiness is typically caused by *Lactococcus lactis* subsp. *maltigenes*, while barny flavors are usually associated with contamination from environmental stable bacteria.

Step 3: Final Answer:
Therefore, the growth of Aeromonas hydrophila in butter causes a fishy flavor (fishiness).