Fresh keeping theory and storage technology of the

Brown rice preservation theory and storage technology

Abstract: introduced and lost the product image and market, and introduced the Japanese brown rice preservation theory; Combined with the reality of Hunan Province, a comprehensive control mode based on low temperature and practical storage technology were put forward

first, the preservation theory of brown rice

the grain storage in Japan is mainly brown rice. The preservation theory of brown rice is that during the storage of grain, it is not only necessary to prevent the harm of insects, mold and rats, but also to delay the deterioration of nutritional components as much as possible, maintain the quality of grain, and achieve the purpose of freshness, So that customers can calculate the mechanical property parameters of the material through the experimental curve in a long time, which has a good color and flavor, that is, to maintain the vitality of stored grain as much as possible

under the same storage conditions, among the three forms of rice, brown rice and milled rice, rice has a shell protection, which is not easy to be eroded by insects and mold, and is conducive to fresh preservation. However, from the perspective of grain circulation and management, it is uneconomical to store rice, because rice accounts for 30% - 40% more storage capacity than brown rice and refined rice, and the corresponding transportation and handling capacity and operation and management costs are increased; At the same time, when rice is processed in cities, there is a lot of dust and rice husks, which seriously pollutes the surrounding environment. Although milled rice takes up less of the storage capacity, it has lost the protection of the cortex. Broken rice and residual dust are prone to the harm of insects, mites and molds, and it is difficult to keep fresh. More importantly, milled rice lost its embryo and completely lost its germination ability, which is called "dead rice" in Japan. In comparison, brown rice not only takes up less storage capacity and reduces workload, but also preserves pericarp and germ. It has germination ability and is still "living rice". Although the storage resistance of brown rice is inferior to that of rice, brown rice, like rice, can maintain freshness for a long time as long as storage measures are appropriate. Based on the above theory, making brown rice enter the circulation, the city will store brown rice, which has great significance. 3. In an environment without vibration; Economic and social benefits and good ecological benefits

as early as the 1970s, China learned the successful experience of storing brown rice in Japan. They acquire, transport and store mainly brown rice. Before sale, brown rice is processed into refined rice to maintain its freshness. Shanghai, Hunan Xiangtan and other places in China have learned from the experience of Japan and combined with the local reality, carried out experiments, achieved success, and gained some experience

second, low temperature storage is an effective method for keeping brown rice fresh

Japan's requirements for keeping brown rice fresh require that in addition to maintaining good germination ability, water content be kept at 14.5% - 15%. This undoubtedly increases the difficulty of safe storage in the southern region of China, which is rich in rice. According to the experience of Japan and China, low-temperature grain storage is an effective method for keeping brown rice fresh

(I) low temperature storage can effectively maintain the germination ability of brown rice. Germination rate is an important index to identify the vitality and freshness of seeds. The slow decline of germination rate indicates that the quality deterioration is also slow. The germinating power of brown rice varies greatly at room temperature and low temperature. According to the Shanghai experiment, the germination rate of brown rice stored for 10 months is more than 85% under low temperature storage (15 ℃); Quasi low temperature storage (20 ℃) at 50%; Only 16% at room temperature. The same results were obtained in the Japanese experiment (see the table below)

Table 1 test results of germination rate of brown rice stored for 3 years

barn type varieties

japonica brown rice (%)

waxy brown rice (%)

Ibaraki japonica brown rice (%)

normal temperature barn

3

1

0

low temperature barn (15 ℃)

100

73

69

(according to 3D tiger understanding)(II) low temperature storage can delay the time of effective temperature accumulation of pests. Pest development and reproduction. There must be a certain effective accumulated temperature. Taking the maize weevil, the first destructive pest in Hunan Province, as an example, under normal circumstances, the starting temperature of maize weevil development is 14.5 ℃, and the effective accumulated temperature required for a generation is 435 degrees per day. The annual effective accumulated temperature in central Hunan is about 1900 degrees per day, and the maize weevil can breed more than four generations a year. Low temperature grain storage is often kept below 15 ℃, and the breeding of maize weevil is inhibited because it cannot obtain the effective accumulated temperature required for breeding. Even in the quasi low temperature warehouse below 20 ℃ (calculated at 17.5 ℃ on average), the effective accumulated temperature in one day is 3 degrees, and it takes 145 days to breed a generation, which greatly delays the time of effective accumulated temperature. The former Xiangtan district grain department is located in Xiangtan County Yisuhe grain station