Rice is exposed to the air directly due to the endosperm, and it is highly susceptible to deterioration by the influence of moisture, heat, insects, and mildew, thus affecting the taste quality of rice; it is easy to produce rice with “aged†and mildew, and the storage of rice is grain. A major problem in the discipline of storage. Safe storage, prevention of mildew, and deterioration of quality are important aspects of rice storage. At present, China's rice storage mainly uses methods such as air conditioning, low temperature, mechanical ventilation and vacuum packaging. With the improvement of people's living standards, the majority of consumers have higher and higher quality requirements for rice. Increasing the level of rice storage technology, extending the period of safe storage, maintaining the quality of rice, and reducing costs are the directions for rice storage. 1 Rice Storage Characteristics Rice loses the protection of the rice husks. The endosperm is exposed and susceptible to insects. The storage stability is worse than rice. The ways in which rice is lost include the loss of physical quality in the process of harvesting, cleaning, transportation, drying, storage, grinding, and sales, and the decline in commercial quality in the process. The rice storage has experienced the longest period of time in this process, with the most serious losses. The characteristics of rice storage are: aging, mildew, insects, rodents, etc. 1.1 The aging of aged rice is characterized by crispy rice, rice grains tending to be sticky and dull, gelatinization and water holding capacity decreasing, viscosity decreasing, fatty acid content rising, and rice soup leaching substance decreasing; rice is hard and not sticky after cooking, and the mouth is tied; There is a taste of Chen. One year of general storage means different degrees of aging. Finished grains are easier to age than raw grains. If rice is high in moisture, high in temperature, low in precision, damaged in lotus root starch and insect pests, it will be aged quickly, and vice versa, especially in the summer rainy season. 1.2 Moisture absorption and moisture return The moisture absorption capacity of rice is related to the processing precision, the content of ground meal and the total amount of broken rice. In particular, wolfberry powder, its strong moisture absorption and with more micro-organisms, easily lead to fever, mold, taste, but also blocking the pores of rice heap, so that the heat is not easy to emit. In addition, Gurito P [1] and others believe that the moisture absorption rate of the film bag is negatively correlated with the water content of rice and is positively correlated with the ambient temperature. 1.3 Moldy microorganisms have fungus (mold, yeast, phytopathogenic fungi, etc.), bacteria, viruses, etc., and molds that are most likely to promote mildew in rice are fungi. In the early stage of moldy mildew, the surface of the rice was gray, dull and grayish, and the rice groove was obvious. In the process of mildew, it is characterized by fever, sweating, and a slight musty odor; the pigments produced by the mold itself and its metabolism cause the discoloration of the rice, causing the original color of the rice grains to disappear, and appear dark, dark, yellow and other colors. Mildew is significantly associated with rice moisture content, ambient temperature, humidity, and gas composition. When the water content is below 12%, mold reproduction is difficult. Wei Yanmei [2] thinks: Below 14%, the water activity AW value is lower than 0.64 at this time. It has a certain inhibitory effect on certain mold spores, and most microorganisms cannot breed. Wang Zhengjie [3] and others believe that molds are greatly reduced below 20°C, and that insect pests are completely inhibited below 10°C, and molds stop moving. Xu Xiaoqiu [4] and others believe that: O2 <2%, CO2> 20%, or O2 <10%, CO2> 10%, can make all kinds of stored grain mold inhibition, at least inhibit the growth of conidia. 1.4 Insect pests are mainly rice elephants. Huang Jianguo and others believe that rice elephants do not lay eggs at temperatures below 11°C or above 35°C. The influence of the gas environment on pests is significant. Wang Ruidong and others believe that CO2 can stimulate the respiration of pests, keep the valves of insects open continuously, and increase oxygen consumption in the body until Oxygen die. Xu Xiaoqiu and others believe that: CO217% ~ 18%, 3 days to inhibit or kill pests; O2 is less than 10%, pests can survive in dormant state; O2 is less than 4%, two weeks of death; O2 is less than 2%, pests 48 hours death . 1.5 Insect pests and rodent pests not only cause the loss of rice quantity, but also seriously affect the quality of rice. The more advanced method of repelling rats is to apply a variety of cross-barrier micelles to the surface of the film, rely on odor, light color, (polarization, fluorescence) to drive the rats. The rodent repellent is mainly cycloheximide (CHI ), tributyltin acetate, dithiobiureas, isothiourea compounds.
