China is the country with the largest total output of fruits and vegetables in the world. With the development of science and technology, the variety of fruits and vegetables is increasing, the output is getting bigger and bigger, and the requirements for storage and preservation technology of fruits and vegetables are getting higher and higher. With the continuous improvement of people's living standards, people's requirements for the freshness, quality and safety of fruits and vegetables are getting higher and higher, and the storage and preservation technology of fruits and vegetables is getting more and more attention.
Fruits and vegetables are rich in nutrients and high in water content, but they are seasonal and regionally strong, and are susceptible to mechanical damage. They are prone to water loss, rot and deterioration during storage and transportation. In order to reduce losses during storage and transportation, in addition to the necessary post-harvest commercialization, it is necessary to adopt appropriate fresh-keeping measures according to the post-harvest physiological characteristics of different fruits and vegetables to minimize the metabolism and delay the ripening of fruits and vegetables. The aging process extends before the shelf. The following is a series of fresh-keeping technologies commonly used in the processing and production of fruits and vegetables by Xiaobian.com, a leading enterprise technology service platform in China.
1. Refrigeration and preservation technology of fruits and vegetables is one of the most widely used fresh-keeping technologies for fruits and vegetables. It uses low temperature (but higher than the freezing point of fruits and vegetables) to inhibit the respiration of fruits and vegetables and the activity of rot-forming microorganisms. The purpose of the storage period of fruits and vegetables. During the process of refrigerating fresh fruits and vegetables, special attention should be paid to controlling the temperature of refrigerating. Too low storage temperature will cause chilling or freezing damage to fruits and vegetables, affecting the storage life and even losing the value of fruits and vegetables. To control chilling or freezing damage, we must first understand the habits of different fruits and vegetables, adopt appropriate refrigeration temperature, and strictly control storage temperature to reduce temperature fluctuations. In addition, pre-cooling treatment in the early stage of fruit and vegetable storage, using gradual cooling treatment and other methods can also reduce or eliminate chilling.

2. Fruit and vegetable modified atmosphere preservation technology The modified atmosphere preservation technology is a preservation technology that aims to extend the storage period by controlling the proportion of gas in the storage environment. For fruits and vegetables, the environment of low oxygen and high carbon dioxide is generally used to reduce the respiration rate of fruits and vegetables, delay the maturation process, and thus improve the storage period. It should be noted that air conditioning is not only a regulation of the gas composition of the storage environment, but it is still a prerequisite to control and regulate the storage temperature. In addition, in order to achieve good results, it is necessary to consider the influence of various factors such as gas composition, temperature and humidity on fruits and vegetables, so that various factors can achieve coordination and promotion.
At present, there are two main forms of modified atmosphere preservation technology: modified atmosphere storage and modified atmosphere packaging. The air-conditioning fresh-keeping cold storage, that is, CA-controlled storage and preservation, is to store fruits and vegetables in the atmosphere-controlled fresh-keeping warehouse. By precisely controlling the gas composition and concentration required for different fruits and vegetables, and strictly controlling the storage temperature, the fruit and vegetable storage period is prolonged. The modified atmosphere packaging, that is, the MA atmosphere storage and preservation, is based on the physiological characteristics of the fruits and vegetables. The fruits and vegetables are first placed in a package suitable for gas ratio, and then stored at a low temperature.
3. Fruit and vegetable preservative preservation technology Preservatives can be divided into chemical preservatives and natural preservatives according to their sources. Although chemical preservatives have a good preservation effect, excessive use can adversely affect human health. Natural preservatives are safe, non-toxic, and highly effective, so they have been increasingly used in fruit and vegetable preservation in recent years. At present, the natural preservatives for fruits and vegetables commonly found at home and abroad include: tea polyphenols, chitosan, garlic extract, propolis extract, orange peel extract, konjac mannan.
4. Fruit and vegetable coating fresh-keeping technology The fresh-keeping technology of fruit and vegetable coating is artificially coating a film on the surface of fruits and vegetables, so as to properly block the pores of fruits and vegetables, inhibit the respiration, reduce the loss of water dispersion, and at the same time inhibit the invasion of microorganisms, thereby achieving the purpose of keeping fruits and vegetables fresh. In addition, the coating film can also avoid or reduce the mechanical damage of the skin of the fruit and vegetable to some extent. The film preservation technology has the advantages of simple operation, low cost, easy availability of materials, and improved appearance of fruits and vegetables, and has been widely used for fruit preservation.
The core of the film-preserving technology of fruits and vegetables is the choice of coating agent. At present, the coating materials commonly used in fruits and vegetables are composed of sugar, protein polysaccharide, sucrose fat, polyvinyl alcohol, monoglyceride and polysaccharide, protein and lipid. Membrane and the like. Fruit and vegetable coating methods include dip coating, brush coating and spray coating.
5. Other fruit and vegetable preservation technology In addition to the above four methods, the current technologies such as enzyme preservation, ozone preservation, irradiation preservation, and ice temperature preservation are gradually applied to the preservation of fruits and vegetables, and have achieved good preservation effect.
Fruit and vegetable ice temperature preservation technology: ice temperature is the temperature range between the freezing temperature of the organism and 0 °C. Preserving fruits and vegetables in this temperature range can maintain the freshness and taste of fresh fruits and vegetables, which is superior to refrigeration or freezing. Preservation technology. At present, ice temperature technology has been widely used in developed countries such as Japan and the United States. However, in China, due to the constraints of cooling induction technology, constant temperature control technology and other related refrigeration technologies, ice temperature technology has not been widely applied.
Enzymatic preservation of fruits and vegetables: Enzymatic preservation is the preservation technology that uses the catalytic action of enzymes to prevent or eliminate the adverse effects of external factors on food, thereby maintaining the original quality of the food. At present, the enzymes used in the preservation of fruits and vegetables mainly include glucose oxidase and cytolytic enzyme.
Radiation preservation of fruits and vegetables: mainly by using γ, β and γ rays generated by ionizing radiation to irradiate fruits and vegetables, ionizing water and other substances inside fruits and vegetables, generating free radicals, killing harmful substances, and thus preserving fresh fruits. Irradiation is generally used as a post-harvest treatment technology for radiation de-worming and bactericidal preservation of tropical fruits such as papaya, mango and banana.
"Common Preservation Technology for Fruits and Vegetables" was edited by China's leading enterprise technology service platform, Xianji. Xixian.com is an enterprise technology service platform, providing technical services for enterprises, releasing project demand information and project outsourcing. It is a gathering place for Chinese enterprises. A gathering place for technical talents.