Study On Water-saving And Pollution-reducing Process Of Soaking Of Glutinous Rice Flour

The production of water-milled glutinous rice flour involves a number of processes,among which soaking holds great importance.The process of soaking aims to eliminate attachments in the glutinous rice raw material such as impurities and bran and obtain hydrated clean glutinous rice,so that the final product can meet hygiene requirements.Water consumption during the process and sewage discharge that follows are alarmingly huge.Moreover,the extended storage of glutinous rice increases the cost of rinsing,causing a serious waste of water resources and raising the burden of sewage treatment.This paper studies the glutinous rice exposed to different temperatures for 180 days,collecting samples every 30 days,analyzing how dissolved matters in the soaking process change with storage conditions,exploring the mechanism of the surface change in glutinous rice,and finally attempting to identify measures to reduce water consumption and sewage discharge in the soaking process.The research results are as follows.According to the measurement results of the water absorption of the glutinous rice in the different storage environments,the results show that the temperature and length of storage period are positively correlated with the water absorption of glutinous rice.Taken together,the optimal effect can be achieved when the soaking temperature is 25?.and the length of soaking period is controlled at 6h.Based on this,glutinous rice that has been stored for different periods of time at different temperatures was soaked,after which the content of dissolved matters was measured.The results show that the temperature and length of storage period are positively correlated with the total of dissolved matters and the content of both soluble and insoluble dissolved matters.In contrast,soluble ingredients are always higher than insoluble ingredients.Moreover,in the soaking process,the amount of dissolved matters in glutinous rice stored at higher temperatures rises more significantly when the storage period is longer.By exploring the mechanism of the surface change of glutinous rice,the causes of the change in the content of dissolved matters can be clearly explained.Focusing on the glutinous rice raw material,this paper measured the physical and chemical indicators,the total amount of mold and the microstructure and analyzed the results to find that when the glutinous rice is stored for a longer period,the protein content decreases overall,fatty acid value increases significantly,the content of reducing sugar first increases and then decreases,and the mold count shows an upward trend.When glutinous rice has been stored at a high temperature,the change in each indicator is especially obvious:the protein content falls more significantly,the fatty acid value increases sharply and decreases at a certain level later,the content of reducing sugar reaches its peak value at the 90^th day of storage,and the mold count increases the most.Therefore,the storage temperature is one of the important factors that affect the change of glutinous rice.The measurement results of the microstructure reveal that particles attach to the surface of glutinous rice,cross-sectional endosperm cells show obvious radiation features,and when the storage period is longer,the particles on the surface of the rice are more widely distributed,particle agglomerations bulge and undulate,the polyhedral sheet structure and the frustum structure of cross-sectional endosperm cells become blurred and the trend of the radiation pattern is unclear and even fades.The subsequent analysis has found a close correlation between various indicators.There is a highly significant correlation between storage time and the amount of dissolved matters,the mold count,fatty acid value,and protein content.In general,the increase in the floury layer on the surface of glutinous rice is because microorganisms obtains nutritious matrix from glutinous rice,digesting,absorbing and utilizing the substances inside and outside the rice,which,combined with the external environment,causes the obvious change in the surface of the glutinous rice.To better cope with the change in the surface of the glutinous rice,this paper conducted dry treatment on the glutinous rice that has been stored for different periods of time prior to the soaking process.After the raw materials of the aged glutinous rice are polished by the dry method of the polished rice polisher,the powdered layer on the surface of the rice grains is first removed,and then the soaking process is performed.After the treatment,the indicator of the amount of dissolved matters and the content of both soluble and insoluble dissolved matters declines significantly,which attests to the feasibility of the treatment.A small amount of powdered layer grinded off by the polishing machine is mainly composed of starch and protein.Most of the past production processes were dispersed in immersion water,causing water pollution.Through dry processing and recycling,waste can be turned into treasure,and good social and economic benefits can be obtained.