Cuts, quality, storage and cooking.
USDA guidance gives most properly refrigerated cooked meat and leftovers 3–4 days at 40°F / 4°C or below. That window assumes the food was refrigerated promptly; reheating later cannot make up for hours spent warm.
There is no single refrigerator limit for all raw meat. USDA gives raw steaks, chops and roasts of beef, pork, veal and lamb about 3–5 days at 40°F / 4°C or below, while ground meat and many organ meats get only 1–2 days.
Raw ground meat has a short refrigerator window: USDA recommends cooking or freezing ground beef, pork, lamb or veal within 1–2 days at 40°F / 4°C or below. Grinding spreads surface organisms through the meat and greatly increases exposed area.
USDA recommends cooking or freezing fresh raw chicken within 1–2 days when the refrigerator is 40°F / 4°C or below. Smell and color can reveal obvious spoilage, but they should not be used to stretch that storage window.
Persistent off odor, a slimy or sticky surface, mold or obvious deterioration are reasons to discard meat. Color alone is less reliable: meat can turn brown as myoglobin changes without necessarily being spoiled, and meat that looks normal can still be unsafe if time or temperature limits were exceeded.
Rubbery chicken does not always mean the same thing. Dry and stringy usually points to overcooking; a springy or translucent center may need more cooking; a breast that felt oddly hard before cooking can point to woody breast.
Lean cooked meats are closer together than most protein rankings make them look: most fall around 27–33 g per 100 g. Cut and cooking water loss can matter as much as the animal itself.
When a skillet turns into a puddle, it is tempting to blame the meat. But muscle is already about 70–75% water; the real question is how much moisture comes out and whether the pan can evaporate it fast enough.
Chicken and turkey breast are the leanest examples, but pork tenderloin can be close. Lean beef supplies more heme iron, and cut choice often matters more than the animal name.
A persistent off odor or slimy, sticky surface is a reason to discard chicken. Color alone is less reliable, and normal-looking chicken can still be unsafe if it was stored improperly.