All food materials are organic in nature. Organic cells grow, multiply and die in due course of time. We eat food and vegetables only when it is mature or ripe. People who have grown tomatoes will know how fast a green tomato turn dark and becomes mushy. Soon it breaks into its molecular components and becomes water and sugary juice making it a puddle. Such fruits are known as perishable fruits. Life of perishable foods can be increased by keeping it freeze inside a refrigerator.
When foods are kept in the refrigerator, bacteria in it become deactivated due to low temperature in it. But they are not killed. Once the food is removed from the refrigerator, they start growing again. So it is better to heat the food well and remove the bacteria before it is placed in the refrigerator.
Bacteria are micro organisms found everywhere on earth like soil, water, radioactive waste, in earth’s crust etc. They also live in parasitic relations as well as symbiotic relations. When food is kept at room temperature for long time, it allows the bacteria in it to grow to dangerous levels and make the food decay faster. Moisture and time are favorable factors for the growth of bacteria.
Bacteria grow rapidly in the temperature range between 40° and 140 ° F. At this temperature range it grows at the fastest speed that it gets doubled within 20 minutes. So this is the danger zone. That’s why meat and poultry are never kept outside of refrigerators. If the temperature is around 90°F, then the meat should not be kept in the open air for a period exceeding one hour.
When you cook raw poultry or meat, always heat them to the minimum internal temperature safe for the material. This will cause all the bacteria inside the raw meat/poultry to die. Oven temperature greater than 235 ° is considered as the safe temperature in this regard.
Roasting to a minimum safe temperature of 145° F will be safe. But the roasted food has to remain in that temperature for at least 3 minutes before anybody eats such food. Some persons have been found to be cooking food at higher temperature. There is no harm in doing so. It only saves the person from the problems of bacteria. If raw meats are left in the danger zone for prolonged period then due to the action of the bacteria it may get rotten. There will be no use even if that meat is cooked at higher temperatures than the minimum safe temperature.