Off-odors from nearby sources — Growth of Streptomyces on straw or in the vicinity of egg storage is most likely to impart which sensory defect to eggs?

Introduction / Context:
Eggs readily absorb environmental odors through their porous shells. Understanding which off-flavors correlate with specific environmental microbes aids in diagnosing storage and facility issues.

Given Data / Assumptions:

• Streptomyces spp. are filamentous actinomycetes common in soil and straw.
• They produce geosmin and related compounds responsible for earthy, musty odors.
• Eggs stored near contaminated straw or dusty areas can absorb these volatiles.

Concept / Approach:
Geosmin (and 2-methylisoborneol) from Streptomyces cause characteristic musty/earthy flavors perceived at extremely low thresholds. While “hay” notes might be present in a barn, the microbial signature specifically points to musty/earthy rather than fishy or cabbage-like notes (often linked to amines or sulfur compounds).

Step-by-Step Solution:

Verification / Alternative check:
Food flavor literature and environmental taint investigations repeatedly associate earthy/musty taints with actinomycete growth on nearby substrates.

Why Other Options Are Wrong:

• Hay odour: could occur from environment, but the signature of Streptomyces is musty/earthy.
• Fishy: amine-related spoilage by certain bacteria, not actinomycetes.
• Cabbage-water: sulfur volatiles, not typical for Streptomyces.

Common Pitfalls:
Confusing general barn odors with the specific microbial geosmin taint.

Final Answer:
musty or earthy flavors