As a general guide, leftover foods such as meat, fish, poultry, pasta, and eggs may be kept refrigerated for 3 to 5 days, depending on previous care. Foods that have been prepared and have remained for 1 to 2 hours in temperatures ranging from 40º F to 140º F have the potential to grow bacteria and become unsafe for consumption. Therefore, keep leftovers safe by cooling them quickly and refrigerate them as soon as possible to keep them free from harmful bacteria growth.
Freezing foods (storing at 0ºF or below) enables the leftovers to be kept for considerably longer periods of time ranging from one to several months after which they begin to deteriorate in flavor and texture. When freezing foods, make sure they are wrapped or stored in airtight containers for best results. After they are thawed, they should be consumed within 2 to 3 days.
As a general rule, use an appliance thermometer to periodically check temperatures in refrigerators and freezers to assure they are adequately cooling foods. It is also important to make sure foods are not packed tightly into refrigerated areas, since cool air should circulate around the food to keep it safe.
Before using leftovers, examine the food for any harmful changes. Common occurrences such as color changes (browning or whitening), excess slime, drying out, cracking, ice crystal formations, mold, dissolving fluids, and rancid odors are all indications a harmful change may have occurred requiring disposal of the food. Although appearance may indicate problems with the food, never trust a sense of smell, feel or sight to totally insure proper inspection, because food can spoil without showing indications that bacteria is present. Therefore, always discard food that may be questionable. When reheating leftovers, make sure the food is rapidly heated to a temperature of 74ºC (165ºF). Liquids such as soups, sauces and gravies should be heated to a boiling point rapidly before being served.