Raw fresh marbled meat Steak
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Processing, handling and storing meat all present opportunities for it to spoil. Spoiled meat may have been treated at improper temperatures or stored for too long, allowing mold or bacteria to infiltrate—yuck! Meat can also be tainted with a food-borne bacteria or virus that's not visible to the naked eye and only shows up after you've consumed it. Cue stomach upset, nausea, vomiting and diarrhea. Common forms of food-borne illness in the United Sates are:

  • Salmonella
  • Norovirus, or Norwalk virus
  • Campylobacter
  • E. coli
  • Listeria
  • Clostridium perfringens

The only way to know in advance if your meat has definitely been tainted by one of these pathogens is through a recall or chemical analysis. In some cases, you may not know what's wrong with the meat, but suspect it's no longer suitable for consumption. Use your best judgement and

if in doubt, throw it out

; it's not worth suffering for.

Step 1: Visually Inspect

Look for

strange coloration

. Fresh meat is red or pink in color. If the natural pink hue is gone or has turned to black, gray or green, the meat may have spoiled because of contamination of yeast, mold or bacteria. Freezer burn or protein denaturation -- which don't pose health risks, but may make the meat unpalatable -- could also be the cause.

Step 2: Smell

A rotten or sulfuric smell is an indication that the meat has spoiled.

Step 3: Look for Slime

Visible mold colonies are one indication of spoilage. They usually appear as white or greenish spots. These colonies also cause a

sliminess

on the surface of the meat. You can see, or feel, this filmy layer, which is a sure indication the meat has spoiled Most meat stays fresh for about four days in the refrigerator at 40 degrees Fahrenheit or below, but it really depends on the type of meat and its packaging. For the best quality and taste when freezing meat, store it in the freezer no longer than six months at a temperature of zero degrees. Wrap it securely in freezer paper, or keep it in its original packaging until you're ready to prepare it. If you plan to freeze meat for longer than two months, wrap it with an additional heavy-duty layer of foil or freezer paper. If you do find your meat has spoiled, dispose of it in the trash as you do other food waste, but

don't compost it

unless you want attract all sorts of critters, maggots and bacteria. Avoid disposing of it in the garbage disposal in your sink too -- the fat, bones and connective tissue can clog up pipes and drains.