Shelf life of frozen food in refrigerator

Most frozen foods can be stored for one year at -17 degrees and for 2 years at -28 degrees. The temperature of refrigerated meat should be about half a degree above freezing point, and the storage time can be up to one month. If carbon dioxide is used to control the air pressure, the storage time can be extended to 2 months. The lower the refrigeration temperature, the longer the food will be preserved. The temperature of the refrigerator compartment is generally controlled between 1-7 degrees, which can prevent food from rotting in a short period of time. Food must be stored in deep freeze before use.

Refrigerating fresh food only inhibits food spoilage, but does not ultimately prevent food from spoiling. The purpose of refrigeration is to slow down the speed of food spoilage. In the temperature range of -1-8 degrees, the lower the temperature in the refrigerator, the slower the growth of microorganisms, and the slower the biochemical reactions that deteriorate the taste, color, texture and nutrients of food. It is very important that food is not contaminated by knives before being refrigerated. Lowering the temperature of food within this temperature range can reduce the risk of poisoning.

Extended information

Francis Bacon, a 17th-century British writer and philosopher, tried to stuff snow into a chicken to freeze it. Unexpectedly, he caught a cold and soon fell ill. Fell down. Even before bacon's unfortunate experiment, it was known that extreme cold prevented edible meat from "going bad." This led wealthy landowners to set up ice cellars on their estates that could preserve food.

These early attempts at freezing food missed the point. It's not so much the degree of freezing, but the speed of freezing, that is the key to freezing meat. Probably the first person to realize this was American inventor Clarence Birdseye.

It was not until the 1950s and 1960s, when household refrigerators became increasingly popular, that frozen foods began to be sold in large quantities. Soon thereafter, Birdseye's famous red, white and blue packaging became a familiar sight in stores around the world.

Birdseye conducted a census of wild plants while traveling in Canada's Labrador Peninsula in the years after World War I. He noticed that it was so cold that soon after he caught a fish it froze solid. He wondered whether this was the key to food preservation.

Unlike bacon, Birdseye lived in the age of the freezer. After returning home in 1923, he experimented with a freezer in his kitchen. Next, Birdseye experimented with freezing various types of meat in a larger freezing plant.

Birdseye eventually discovered that the fastest way to freeze food was to squeeze the meat tightly between two frozen metal plates. By the 1930s, he was ready to start selling frozen meals produced at his Springfield, Massachusetts, factory.

Frozen food quickly became big business for Birdseye, and even before he invented the efficient double-plate freezing process, his company was producing 500 tons of fruit a year. and the amount of frozen vegetables.

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