1, China's current national standard "Rice" (GB 1350- 1999) stipulates that rice is divided into five grades according to roughness and head rice rate, except for the national standard "High Quality Rice" (GB/T 1789 1-
2. According to national standards, the chalkiness rate of first-class high-quality rice is below 10%, second-class1-20%, third-class 2 1-30%, and the chalkiness rate is above 30%. It may be necessary to rebuild the above standards recently, and the chalkiness rate of high-quality rice should be improved. For example, the chalkiness rate of first-class high-quality rice in the national standard is below 5%.
3, the definition of rice is divided into the following categories:
3. 1 Early indica rice grains with shorter growth period and earlier harvest period generally have larger white bellies and fewer horny grains.
3.2 Late indica rice grains with long growth period and late harvest period generally have smaller or no white rice grains and more horny grains.
3.3 japonica rice valley? The seeds of non-waxy japonica rice are generally oval, sticky and not swollen.
3.4 The fruit of indica glutinous rice, brown rice is generally rectangular and slender, and the rice grains are milky white and opaque.
3.5? In the fruit of glutinous rice with stalk type, the brown rice is generally oval, and the rice grains are opaque and translucent. Say yin and glutinous)
3.6 roughness? Percentage of brown rice (including incomplete folding and semi-calculation) after hulling of clean rice to sample quality.
3.7 polished rice polished rice brown rice is broken when it is processed into first-class rice with national standard accuracy.
3.8 Head milled rice rate The percentage of head milled rice in the quality of clean rice samples.
3.9 Imperfect particles include the following particles with edible value:
3.9. 1 Immature grain: The grain is immature and not full, and the appearance of rice grains is all powdery.
3.9.2 Insect-eating particles: particles that are eaten by insects and damage the endosperm.
3.9.3 diseased grains: grains with diseased brown rice embryos or endosperm.
The conditions for selecting good rice through extended data are:
Look at hardness: The harder the rice is, the higher the protein content is.
Look at the white belly: there is often an opaque white spot on the belly of rice, which is usually too much water. After harvest, the belly white of immature and immature rice is larger.
Look at the burst waist: if one or more transverse cracks appear on the rice grain, it means that it is burst waist rice with low nutritional value.
Look at the yellowing of rice grains: the yellowing of rice grains is due to the low nutritional content in rice, which affects the taste.
Look at the aging: The rice with gray powder or white grooves on the surface is old rice, and the more it is, the older it gets.