If your steak is past its use-by date or has a slimy texture it's destined for the trash and not your grill. The top telltale signs that your steak is bad are a greenish color, a slimy texture and an unpleasant odor. These symptoms are a sign that bacteria is growing, and consuming spoiled meat can make you very sick.
If you notice that your steak is a greenish or yellow color it's a clear indication that it's gone bad. However, some discoloring of red meat is normal and doesn't necessarily mean that your steak is spoiled. The color of the steak changes because of different proteins that are formed when the meat is exposed to light, oxygen or other elements.
A steak will also begin to spoil if it becomes wet or sticky from a buildup of bacteria. The best way to test the moisture of a steak is by touching it. A fresh steak is firm to the touch and will have balanced moisture.
An unpleasant odor is a sure sign that your steak is past its prime. Spoiled steak has a potent smell that's similar to ammonia or sulfur.
The last thing you want is to give your mother-in-law food poisoning. To prevent this, you should check the temperature of your refrigerator regularly to make sure that it is set correctly. You should also avoid leaving your raw meat out at room temperature as this increases the likelihood that it will go bad.