Good and Bad classification of chicken (Gallus gallus domesticus)

Classification is based on freshness, sensory quality, and safety.
Good (Fresh) Chicken
Color: Pink to light reddish. No green or gray patches.
Odor: Neutral or mild meaty smell.
Texture: Firm and elastic. Springs back on touch.
Skin: Moist but not slimy. No sticky layer.
Eyes and comb in live or dressed birds: Clear eyes. Bright red comb.
Packaging: No swollen pack. No excess drip.
pH: Around 5.8–6.2.
Microbial load: Low. No visible spoilage.
Bad (Spoiled) Chicken
Color: Gray, greenish, or yellow discoloration.
Odor: Sour, rotten egg, or ammonia smell.
Texture: Soft, mushy, or sticky.
Skin: Slimy with tacky surface.
Eyes and comb: Dull eyes. Dark or bluish comb.
Packaging: Bloated pack due to gas.
pH: Above 6.4.
Microbial load: High. Slime or mold may appear.
Decision rule: Any off-odor or slime means reject. Cooking does not make spoiled chicken safe.