The Research On Evaluation Technology Of Eating Quality Of Cooked Rice Based On Instrument

In order to research the evaluation technology of eating quality of cooked rice,this paperselected the south indica and northeast japonica as experiment materials,and applied theelectronic nose technology, image processing and texture analyzer to study the quality of odor,appearance,palatability of eating quality of cooked rice respectively,and used the method ofprincipal component analysis to analyzed the odor indicators and stepwise regression analysismethod to analyzed rice appearance and palatability.Finally, the method of odor evaluationbased on electronic nose technology,and the method of appearance evaluation based on imageprocessing technology,and the method of palatability evaluation using texture analyzer wereestablished.The main conclusions were summarized as follows:(1) Two principal components Z1and Z2were determined by the method of principalcomponent analysis, their cumulative variance contribution rate has reached89.352%,whichcan represent most of the odor information of cooked rice;the comprehensive evaluationmodel constructed by two main components and its variance contribution wasZ=0.789Z1+0.104Z2，and its predict effect was better, which consistented with the results ofsensory evaluation, so using the electronic nose to assess the rice odor quality isfeasibility.Thereby,an odor quality evaluation approach was established based on electronicnose.(2)Whether indica,or japonica,there is a significant correlation between appearancemeasurement indicators and each indicator of appearance sensory evaluation of cooked rice;the regression coefficient of equation reached a significant level(P＜0.05),which builded byeach appearance index of sensory evaluation as the dependent variable and each appearancemeasured indicators as the variables, so the regression equation established is valid;in thelast,the regression equation is validated,whose appearance predicting results has a goodcorrelation with those of sensory score, the fitting degree of the linear is higher.Therefore, themethod based on image processing can be used in place of the sensory evaluation to evaluatethe rice appearance.(3) The each texture measurement indicators and palatability evaluation indicators ofcooked rice has a significant correlation; the regression coefficient of equation reached asignificant level(P＜0.05),which builded by each palatability index of sensory evaluation asthe dependent variable and each texture measurement indicator as the variables, so the regression equation established is valid; in the last,the regression equation is validated, whosepalatability predicting results has a good correlation with those of sensory score, the fittingdegree of the linear is higher.Therefore, the texture analyzer can replace sensory evaluation toevaluate palatability of cooked rice for instrument evaluation.