Steak

Whole-muscle beef gets a considerably longer refrigerator window than ground beef — 3–5 days — because its bacteria are confined to the surface. Store it on the bottom shelf in its packaging.

If you have vacuum-sealed steak, leave it sealed. Vacuum packing removes the oxygen that spoilage bacteria need and can extend the window substantially; the "use by" date on a sealed pack assumes it stays sealed. Once you open it, the ordinary 3–5 day clock applies.

For freezing, overwrap the store tray. Steak's long freezer window — up to 12 months — depends entirely on keeping air off the surface, and supermarket film will not do that for a year. Vacuum sealing is genuinely worth it here if you freeze meat often.

Do not salt steak you intend to store for several days; salt draws moisture to the surface and gives spoilage bacteria a wetter environment to work in. Salt just before cooking, or dry-brine uncovered for a day at most.

Whole cuts: cook to 145°F and rest 3 minutes — color is not doneness.

A steak spoils from the outside in. Bacteria land on the exposed surface and work inward slowly, which is why the interior of a whole cut is essentially sterile and why searing the exterior is sufficient to make a rare steak safe to eat.

The organisms responsible at refrigerator temperature are cold-tolerant spoilers that break down surface proteins into amines — the source of the sour, faintly ammonia-like smell of beef that has gone too long. The accompanying slick, tacky film is bacterial biofilm. Both are late-stage signs.

As with ground beef, color is unreliable. Vacuum-packed steak often arrives a dark purple-brown because there is no oxygen to bloom the pigment; it turns red within minutes of opening. Dark patches where the meat pressed against packaging are likewise normal.

Freezer burn on steak is a quality problem, not a safety one. The gray, dried patches are simply areas where surface moisture sublimated away. They will be tough and bland, and can be trimmed off, but the meat beneath is safe.