What are the methods of food preservation?

What are the methods of food preservation?

What are the methods of food preservation? As the saying goes, we should keep good eating habits, eat more fruits and vegetables that are beneficial to our health, understand the characteristics and preservation methods of food, and make our body healthier. Let's learn about the methods of food preservation.

What are the methods of food preservation? 1 1, stored at low temperature.

Low temperature storage is a common method to store cooked food. Its main principle is to effectively inhibit the growth and reproduction of microorganisms, reduce the activity of enzymes, weaken the chemical reaction in food, and better maintain the original flavor and nutritional value of food. Low temperature storage can be divided into refrigeration method and freezing method according to its temperature, and the refrigeration temperature is above freezing point.

Frozen foods mainly include vegetables, fresh meat, fresh fish, fruits, dairy products, cooked products and semi-finished products. Freezing method is to freeze food in an environment below freezing point, which is suitable for storing animal food. Freezing can preserve food for a long time without spoilage.

However, after long-term storage, although the quality of food has not changed much, its moisture content has decreased, its back-nourishing value has decreased and its taste has deteriorated. In addition, when more than two kinds of food are stored in the same freezer, they should be sealed and isolated with non-toxic food bags. Prevent odors from polluting each other. At the same time, it can also reduce the loss of water in food.

2, high temperature storage method

High temperature storage is a common method of food storage in catering industry. Because microorganisms have weak tolerance to high temperature, they can effectively kill microorganisms and destroy the activity of enzymes when the temperature rises, which can prevent the influence of microorganisms on food and achieve the purpose of storing food.

The method is to cook or steam the food thoroughly (reaching the high temperature above 100 degrees), take it out or soak it in the original soup, and put it in a cool and ventilated place without stirring to prevent the food from being polluted again. This method can keep food from spoiling for a long time. This method is suitable for the preservation of finished and semi-finished products of animal foods, and also for the preservation of dry foods such as water.

3. Ventilation storage method

Ventilation storage method is mainly suitable for preserving grain, dry grain and food that needs air drying. Their characteristic is that they are afraid of mildew and covering. For example, rice, flour, peanuts, vegetables and other foods need ventilation during storage, which can make mold difficult to grow, maintain the original ingredients of food and reduce mildew.

4, pickling, pickling, sauce, bubble storage method

This method is generally to add salt, sugar, vinegar, sauce and spiced food in a certain proportion to make the food absorb to a certain concentration. Inhibit the growth of microorganisms and achieve the purpose of long-term preservation of food. For example, pickled products include salted radish strips, salted beans, sweet and sour garlic and so on. Pickled products include spiced kohlrabi, pickled cucumber and pickled cabbage. Pickled products include pickled cabbage, pickled pepper and pickled eggplant.

The nutritional value of food generally treated by salting, pickling, dipping and dipping. Will be reduced, because some vitamins and inorganic salts in food are destroyed and lost, especially the fibrous muscles of animal food will become hard and difficult to be absorbed and digested by the human body. However, after processing and cooking, the flavor is rich and the taste is excellent. This method of storing food is simple and easy, and it is widely used in catering industry.

5. Smoked storage method

Smoking is a method of smoking and baking food with smoke produced by incomplete combustion of sawn, loose branches and other materials. Smoked food not only reduces the moisture inside the food, but also has the function of sterilization and preservation, and wood tar and creosote oil adhere to the surface of the food, which can prevent the growth of bacteria and thus achieve the function of antiseptic storage. The common smoked products are smoked fish, smoked chicken and bacon.

6, vacuum sealing preservation method

Vacuum sealing preservation method is a method to keep food in a vacuum state without contact with microorganisms in the air, such as canned products and vacuum packaging products. This method is suitable for the preservation of various foods.

With the continuous development of science and technology, there are more and more ways to store food, such as nuclear radiation storage method and modified atmosphere method. Their main principle is to control or kill microorganisms growing in food, delay the metabolism of internal tissues of raw materials, thus prolonging the storage time of food, improving the storage quality and achieving the purpose of preservation.

What are the methods of food preservation? 2 condiments:

Put it in the refrigerator when it is not used, which will help to extend the shelf life. The shelf life of processed condiments in unopened state is 1-2 years. However, after being opened, it is placed in a kitchen with high room temperature, even near a gas stove, and the ambient temperature is high, which is easy to deteriorate. For example, vegetable oil, soy sauce and vinegar can only be preserved for 2-3 months after opening; Peanut butter, salad dressing, tomato sauce and other sauces can only be stored for 1-3 months after opening.

Rice category:

Unpack the package and put it in a sealed box. The rice packed at home is packed in large packages, and the unopened shelf life can generally reach 1-2 years. After the big rice package is opened, the outer packaging bag can be taken out and put into sealed containers such as cylinders and barrels, and placed in a cool and dry environment.

Powder:

Try to buy small packages. Flour, cake powder, etc. After opening, it is easy to absorb moisture and agglomerate, and mildew occurs. Their shelf life and storage method after opening are similar to that of rice. Milk powder has high sugar content and fine particles, and it is easier to regain moisture and deteriorate after opening, so don't put it in the refrigerator and try to eat it within 1 month. Milk powder should be sealed in time and stored in a dark, dry and cool place.

Nuts:

Put it in a sealed jar. The shelf life of unopened nut products is generally 8- 12 months. If you can't finish it in a short time, cover the jar or seal the bag in time to reduce contact with air and moisture.

Drinks:

It is best to drink it within 24 hours after opening. Different types of drinks are different. Carbonated drinks can be stored in the refrigerator for 3-5 days.

Fruit and vegetable drinks, such as hawthorn juice and citrus juice, are very acidic and microorganisms are not easy to reproduce. It is no problem to put it in the refrigerator for 2-3 days after opening, but the nutritional value is reduced. Peach juice and pear juice have low acidity and relatively short shelf life.

What are the methods of food preservation? What are the ways to preserve meat food?

1. Refrigerate

We eat some meat food in our daily life. If we can finish it in a short time, we can actually put it in the refrigerator. If it is some fresh meat food that we usually eat, it is no problem to keep it in the refrigerator for 24 hours. Just wrap a layer of plastic wrap on the surface of fresh meat and put it in the refrigerator.

Step 2 freeze in the refrigerator

If we buy a lot of meat and can't finish it in a short time, the best preservation method is to put it in the freezer of the refrigerator, but it should be noted that this preservation method is not suitable for some processed meat products, such as ham we eat.

Step 3 store at room temperature

This preservation method is more suitable for the preservation of some processed meat foods, such as bacon or some sausages. These foods will contain a lot of salt, and even if they are stored at room temperature, they will not go bad easily. Moreover, meat foods like sausages will contain some antiseptic ingredients, so you just need to pay attention to ventilation and avoid sunlight when storing. Don't worry about the rest at all.

What are the preservation methods of meat food? There are so many ways to preserve meat food. In daily life, if you want to preserve meat food, you must first distinguish the varieties of meat food. If it is fresh meat, it is best to keep it in the freezer or freezer of the refrigerator. It is not recommended to store at room temperature, which is very easy to deteriorate.