Change In Microorganism And The Processing Quality Of Freshly Harvested Wheat During Storage

To explore the law of microbial and quality’s variation in processing procedures of new harvest of wheat during storage, a research is carried out which simulated for store in China’s four major stored grain ecological region: Mongolia-Sinkiang ecological regional 15 ° c, 50% RH(W1) North China ecological regional 20 ° c, 65% RH(W2) Central China ecological regional 28 ° c, 75% RH(W3) South China ecological regional 35 ° c, 85% RH(W4).This paper measured wet gluten, gluten index, protein hydrolysis activity, falling number and rheological properties of the new harvested wheat during the storage period of 0 to 180 days. An orthogonal experimental designed based on previous experiments to explore the influence between different storage temperature, moisture and temperature x water and wheat germination potential, germination rate, fatty acid value, TDS values, the shape of the grain and gluten protein, and external mold amount, internal mold amount. Results show:The content change of wet gluten of the new wheat harvest sample in the process of storage change is not obvious, whether it’s the sort of storage under the condition of storage. Four samples in the wheat gluten index peaked in about 60 days after a significant rise in initial stage of storage gluten index; low temperature and humidity storage of samples of wheat gluten index basically keeps stable in subsequent storage, while under the condition of high temperature and high humidity storage of samples of wheat gluten index fell, wheat gluten index under different storage conditions show different changing laws.SDS- sedimentation value(SDS- SV) of new harvest wheat in the process of storage, gradually increase for initial storage period, and decline gradually after-ripening, under the condition of low temperature and humidity storage of samples of wheat SDS- sedimentation value expression is slowly decrease, and storage of samples of wheat decreased under high temperature and high humidity have a big decline.The wheat protein hydrolysis activity has remained at a low level under the condition of low temperature and humidity storage, and keep increasing gradually under the condition of high temperature and high humidity storage, before and after the maturation period showed that under the condition of high temperature and high humidity storage samples of wheat protein hydrolysis degree is higher than that of low temperature and humidity storage samples.The toughness of the dough extensibility(resistance) increase firstly and then remained stable in W2, while other three samples are characterized by lower trend. The dough stickiness(extensibility) have dropped in W1 while increase in W2 early, then decrease. W3 and W4 continue to increase, W4 increased more significantly than the W3. The gluten strength in W1 has a tendency to increase. And increase in W2 early period, stable late basically. Continues to remain the same in W3, and first remains unchanged then decreased in W4.The germination potential and germination rate of new harvest wheat during storage reduced gradually, and fatty acid value and TDS are continually increased. The dyeing of wheat grain endosperm area as the extension of storage time is getting smaller, while wheat embryo will change corresponding. The particle size of wheat gluten protein become smaller with the extension of storage time, reducing the viscoelasticity of wheat gluten.Wheat catalase activity and storage temperature has a good correlation, R2 = 0.9699. Content of wheat mildew and impregnation rate and has a direct proportion relationship between hydrogen peroxide enzyme activity.