Research On Correlation Of Sensory Quality Of High-quality Rice In Guizhou

This paper selected 5 high-quality rice and 2 hybrid rice from Guizhou as the research object,and studied the correlation between physical properties,chemical characteristics,aroma components and sensory quality of rice,and comprehensive evaluation of these indicators.Main results are as follows:1.Correlation between physical properties and sensory quality of rice:sensory evaluation of 7 rice samples showed that the sensory score of high-quality rice was higher than that of hybrid rice,among which the sensory score of dalixiang was the highest,and neiyou5H25 was the lowest.The correlation and principal component analysis show that rice elasticity 1.29~1.30 mm,chewability 31 m J,rice grain elongation 20~30%,expansion rate 150~160%,rice soup light transmittance absorbance value 19 ~20,rice soup dry matter content about 50 mg/g has relatively best sensory quality of rice;The important factors influencing rice sensory scores are chalkiness and chalky rice grains,followed by swelling rate,The correlation and principal component analysis show that rice elasticity 1.29~1.30 mm,chewability 31 m J,rice grain elongation 20~30%,expansion rate 150 ~160%,rice soup light transmittance absorbance value 19 ~20,rice soup dry matter content about 50 mg/g has relatively best sensory quality of rice;The important factors influencing rice sensory scores are chalkiness and chalky rice grains,followed by expansion rate,length-width ratio,rice elongation,rice soup p H and appearance structure.2.The correlation between chemical composition and sensory quality of rice showed that the best eating quality of high-quality rice is the amylose content of 13.61-16.53%,when amylose content was 16%,crude fat content was 0.4%,and total starch content was 78%,rice has the best sensory quality.The main chemical characteristics that affect the sensory quality of rice are ash,crude fat,and amylose by correlation and principal component analysis.3.The research on the correlation between aroma components and sensory quality of rice: The analysis of electronic nose shows that PCA is better than LDF.The volatile components of rice were analyzed by GC-MS showed that aldehydes,olefins,alkanes,ketones and esters were included in rice.The 7 kinds of rice all contained the characteristic aroma substance 2-acetyl-1-pyrroline,The content of dalixixiang was 0.673% at the most,followed by the 0.407% of dalixiang.The ROAV analysis showed that 1-octen-3-ol,hexanal,benzaldehyde,octanal,phenylacetaldehyde,trans-2-octenal,and furfural are present,which give special flavor in 7 kinds of rice.4.Comprehensive evaluation of the taste of rice with electronic tongue: the results of PCA analysis of the electronic tongue show that the total contribution rate is 81%,which can reflect the overall information of the 7 rice samples,the DI value reached 98.9%,indicating that the electronic tongue made a very good distinction between the taste of different rice samples and the identification of the subtle differences that human taste buds could not identify.the rice taste evaluation model was established by the partial least squares regression analysis(PSL),and the correlation coefficient reached 0.954,prediction error is within 10%,which could predict and distinguish the taste of different varieties of rice.The sensory evaluation,physical properties,chemical properties and aroma components of the 7 kinds of rice were analyzed,and the order of the excellent quality of the 7 kinds of rice was as follows: dalixixiang?dalixiang?jinmazhan?fengyouxiangzhan?yuzhenxiang?Yliangyou585?neiyou5H25.