Lentils Alias ​​beans, hedgerow beans, Emei beans, eyebrow beans, etc., is a cultivar of leguminous lentils, perennial or annual vines. The edible portion is tender or mature beans. Its storage and processing methods are many and can be pickled, canned or made into dried vegetables, and can also be frozen and preserved. The freeze-thawed preservation of lentils is very good, and the quality and flavor after thawing are close to that of fresh vegetables. First, the principle of quick-freezing preservation of long-term preservation of lentils can be frozen by low temperature inhibition of microbial and enzyme activity. Some microorganisms that are not tolerant to low temperatures may be killed by the effects of freezing and freezing. However, the main role of low temperature after freezing is to inhibit the metabolic activities of various microorganisms. Once the ambient temperature rises, most of the microorganisms can still resume their activities and continue to decompose and destroy the vegetable products. Freezing the low temperature can also inhibit the enzyme activity of catalyzing various biochemical reactions in vegetables, reduce the speed of various enzymatic reactions in fast-frozen vegetables, and thus delay the changes in color, flavor, quality and nutrition of vegetables. Second, the quick-freezing process (a) process selection process → processing → quick freezing → packaging → preservation → thaw (b) operating points 1. Choice of materials. Use dwarf varieties with low fiber content, low moisture content, thick flesh, slow seed development, and green or dark green color. The size of the earthworm is required to be moderate, uniform, uniform and consistent, free of pests and diseases, no mechanical injury, no decay and deterioration, and the maturity has reached the requirements for quick frozen preservation. It is best to harvest fresh soybean meal products soon. 2. deal with. 1 Finishing: The selected soybean meal should be removed at both ends and side ribs, cross-cut into silk or cut into pieces longitudinally, which is convenient for rapid heat removal, freezing and thawing to meet food requirements. 2 Cleaning: Cleaning can remove dust, mud, and a lot of microbes attached to the surface of the soybean meal. 3 Blanching: To effectively destroy the activity of the enzyme, prevent the enzymatic browning during the quick-freeze preservation. Before the freezing, hot water is used for short-time blanching, ie, the cleaned pods are placed in hot water at about 100°C and blanched for 50-60 seconds. During the blanching, constant stirring is needed to make the blanching uniform. . A certain amount of sodium chloride or calcium chloride can be added during the blanching to prevent oxidation and discoloration of the product. 4Cooling: After blanching, quickly remove the soybean meal and put it in chilled water at 3-5°C to reduce the damage caused by the thermal effect on the quality and nutrition of the raw materials and freeze the product as soon as possible. Cold water spraying or cold air cooling may also be used. Cool and other methods for cooling. 3. Frozen. Soybean meal can be taken into the bamboo basket or plastic basket before freezing to drain the moisture left on the surface of the raw material during the pre-treatment process, and the moisture on the surface of the raw material can also be drained by using an apparatus such as an oscillating machine or a centrifuge to avoid the raw materials in the freezing process. Stick or stick to each other on the freezing device. Then the raw materials can be immediately put into the freezing plate or placed directly on the conveyor belt, and sent to the freezing device for freezing. Generally, it is necessary to quickly and uniformly freeze with a low temperature of -30°C in a short time. 4. Packaging, preservation. The frozen product is to be packed in polyethylene plastic film (0.5kg/bag) and packed at the same time. Then put it in a cryogenic refrigerator that is close to the freezing temperature. It requires low temperature and stability during preservation. Suitable storage temperature is -18 °C - 21 °C, the general safe storage period of 12-15 months. 5. thaw. Frozen foods must be thawed prior to consumption to make them crystallize in ice and return to a fresh state before cooking. The thawing process should be rapid. It can be carried out in the refrigerator, at room temperature, in cold or warm water, or directly in boiling water to thaw. Microwave ovens work better. After freezing, the vegetable tissue undergoes significant changes after thawing. Therefore, once the frozen vegetables are thawed, they should be cooked immediately. At the same time, the cooking time should be short, and it can no longer be frozen and preserved. China Agricultural Network Editor