Question

Dun spoilage in the cured fish products is caused by the growth of

• A. Drosophila casei
• B. Sporendonema epizoum
• C. Aspergillus spp
• D. Salmonella typhi

Hint:

Salted fish defects are common exam topics:
1. Red Heat: Caused by halophilic bacteria (Halobacterium).
2. Dun Spoilage: Caused by halophilic fungi (Sporendonema epizoum).
Always keep moisture low and storage cool to prevent these.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
The question refers to a specific type of spoilage in dried or salted (cured) fish known as "Dun spoilage" and asks for its causative agent.
Detailed Explanation:

• Nature of Dun Spoilage: Dun spoilage is characterized by the appearance of numerous small, black or brown spots on the surface of salted/dried fish. It typically occurs in products with a moisture content of around 15-20% and a high salt concentration.

• Causative Agent: It is caused by the growth of halophilic (salt-loving) fungi. The primary organism responsible is Sporendonema epizoum (also known as Wallemia sebi). This fungus thrives in salted fish and produces pigmented spores that give the "dun" (brownish-grey) color.

• Evaluation of other options:
• Drosophila casei: Is a fly (cheese fly) whose larvae (maggots) can infest fish but doesn't cause "dun" spots.

• Aspergillus spp: Are common molds but are not specifically associated with the "dun" spoilage of heavily salted products.

• Salmonella typhi: Is a bacterial pathogen, not a spoilage mold.

Step 2: Final Answer:
Dun spoilage is caused by Sporendonema epizoum.