Research Of Rapid Detection Of Nutritional Quality And Degree Of Milling In Rice Based On The Near Infrared Spectral Technology

Most of the major nutrients of rice are distributed in bran layer, will be losed with the grind working and caused the nutrients can not be fully utilized; at this stage, people began to focus on the nutritional value of whole grains, and thus study of the influence of the degree of milling to rice quality characteristics have the vital practical significance, but the method used for the study is time-consuming, labor-intensive, and contaminate the environment. Near-infrared spectroscopy is a detection technology of fast, forthright, convenient, no damage and no pollution. This study uses Near Infrared Spectroscopy Technique research quality characteristics of rice in different processing accuracy, established prediction model of nutritional quality and degree of milling of rice, results showed that:1. In this experiment, in order to investigate the effects of nutritional and sensory quality milling and correlation analysis, the 60 of different degree of milling rice were involved. Researches have shown that: The relationship between milling time and degree of milling(DOM) in rice which presented as a function of a quadratic equation, and there are significant differences in different variety of rice. With the increasing of DOM, the chemical ingredients of protein, fat, ash, phytic acid and other nutritional components in rice were reduced, while the brightness value(L *) which affecting the sensory quality of rice was increased gradually; all indicators were measured have the order of relevance with DOM in this studies were showed that: phytic acid(PA) content > chroma b* value> ash> fat> Brightness L*> protein> chroma a* value. The correlation of rice nutrition indicators with DOM by the regression relationship showed that the protein content have the lowest correlation with degree of milling, thus excluding protein indicators at a later trial, other indicators are involved in the research of the NIR model.2. Select 20 varieties of rice on the basis of correlation experiments, then screening, husking, milling and obtained 154 different machining accuracy rice under laboratory conditions, at the same time, collected 19 different precision rice samples from Hunan rice industry under pilot plant conditions, that all of 173 different precision rice samples produced, and construct each parameters model of particles and rice by XDS NIR instruments from FOSS and DA7200 near-infrared instrument from perten. In order to obtain a more comprehensive study for optimal model results, three indicators of fat, ash and phytic acid were compared simultaneously between dry and wet base model, since water is the main factor affecting rice, so moisture also modeling analysis in the study. Those will provide a more theoretical basis for comprehensive study in degree of milling rice. From the experimental results obtained, the model established by XDS near infrared instrument are superior to DA7200 near infrared, but both of them are can be used for practical applications, and XDS near infrared instrument established the wet basis index content model is superior to the index based on a dry basis, powder rice model is better than particle model, the results of powder rice equivalent particle models established by DA7200 NIR instruments.3. Two instruments can be used in practical applications through the above study, but based on instrument performance and structural configuration, XDS instrument more suitable for research experiments, DA7200 instrument more suitable for online monitoring, in order to achieve online monitoring, this experiments collected particle samples were predicted degree of milling use threshold value division and partial least squares discriminant analysis(PLS-DA) by DA7200 near-infrared instrument, As far as the threshold value division method, the highest accuracy of prediction precision by fat and phytic acid content, are 84.21%, ash forecasting accuracy machining accuracy of 73.68%, the accuracy of machining accuracy(L *, a * and b *) were 78.95% forecast, 68.42% and 78.95% by chroma, the accurate prediction rate of 78.95% precision by DOM, while, the accuracy rate predicted by PLS-DA method precision was 89.47%, which higher than the predicted threshold method.In summary, predict the quality of different precision rice by near infrared spectroscopy which quick, simple, no damage is possible; and on-line monitoring of rice processing accuracy through the PLS-DA method can be implemented, the method is simple and easy to operate, at the same time, it was avoiding some errors caused by manual methods, which provides a more comprehensive theoretical basis for the rice processing.