Packaging effect – Poultry stored in polyethylene bags tends to be spoiled predominantly by which microorganisms under chill, mildly oxygen-limited conditions?

Introduction / Context: Packaging influences the spoilage microbiota. Polyethylene bags provide moisture retention and some oxygen limitation but usually still permit enough oxygen for psychrotrophic aerobes to act on poultry.

Given Data / Assumptions:

• Poultry is packaged in simple polyethylene (not high-barrier vacuum/MAP).
• Storage is chilled; some surface moisture persists.
• We seek the most typical spoilage group in this scenario.

Concept / Approach: In non-barrier poly wraps, oxygen is present and water activity is high. Psychrotrophic aerobic Gram-negative rods such as Pseudomonas and the related Achromobacter complex thrive, causing slime and off-odors. True vacuum/MAP would shift flora more strongly to LAB, but simple poly does not eliminate oxygen sufficiently.

Step-by-Step Solution: Assess package permeability → PE bags allow some oxygen transmission. Match microbial ecology → Pseudomonas–Achromobacter dominate aerobic, moist, chilled conditions. Exclude others → LAB dominate in stricter oxygen limitation; thermophiles are irrelevant at chill. Therefore select the Pseudomonas–Achromobacter group.

Verification / Alternative check: Plate counts from bagged poultry commonly recover high Pseudomonas/Achromobacter numbers correlating with slime and taint development.

Why Other Options Are Wrong: Alcaligenes alone is less predictive; heterofermentative LAB dominate in vacuum/MAP, not simple poly; catalase-negative cocci are not the principal spoilers here.

Common Pitfalls: Assuming any plastic wrap equals anaerobiosis; permeability matters greatly.

Final Answer: Pseudomonas–Achromobacter group.