Feeding Sitophilus Zeamais Influence Storge Quality Index For Rice

Study on judging index of the rice storage quality in different storage years hadthe extremely significant role for rice storage and processing. There are significantdifference in rice storage quality between different storage time and the insectfeeding. The rice storage quality indexs in different storage year and Sitophiluszeamais feeding were studied in this paper. The main storage indexs such as electricalconductivity (ECR), malondialdehyde (MDA), fatty acid values (FAV), catalase(CAT) and peroxidase (POD), rice volatile were determined. The results showed thatECR, MDA, FAV increased gradually with the rice storage time extension,meanwhile, CAT, POD reduced gradually. These results indicated that these indexcould be indicators to judge the rice storage. The content of ECR, MDA, FAV, CATand POD in new rice was16.23(μS/(cm·g)),0.43(umol/g),13.41(KOH mg/100g),15.20(mg/g) and155.87(U/g) individually. The content of these indexs in rice afterfour storage years was72.25(μS/(cm·g)0,1.03（umol/g）,41.60(KOH mg/100g),6.29(mg/g),26.53(U/g) individually. Compare with the freash rice, the values ofECR, FAV, POD in four years storage had significant difference (P<0.05). Pests notonly reduce the weight of the feeding of rice,but also affecte rice storage quality andfood quality. The storage quality rice infected by the different population densitiesof Sitophilus zeamais and it feeding different time were studied. The results showedthat ECR, MDA and FAV increased gradually and CAT, POD gradually reduced withthe storage the extension of time and with the increase of population densitySitophilus zeamais. The population density of four Sitophilus zeamais/kg, in additionto infection time1W, catalase activity was significantly in other infections (P<0.05);peroxidase was significant in four difference infection stages; in the insect density is8Sitophilus zeamais/kg, infection time of2W and3W f atty acid value was significant(P<0.05); the population density is16Sitophilus zeamais/kg, in addition to infectiontime1W conductivity was difference significantly in other infection time (P<0.05), inthe infection of3W and4W malondialdehyde was difference significant (P<0.05).Description of Sitophilus zeamais infection on rice quality especially fatty acid andconductivity were significantly. Population density and the time of infection fordifferent storage quality have different effect, when the population density is4Sitophilus zeamais/kg already for the storage quality had significant influence. When the infection time is2W, rice storage quality had significant effect. The research forthe guidance of rice scientific storage and pest control measures is of great theoreticalsignificance. The content of volatile was increased with storage time and theSitophilus zeamais population density. Chemical components of rice volatiles afterSitophilus zeamais feeding were detected were tridecane, tetradecane, pentadecane,2,6ditert butyl4methylphenol,2-methyl decane, heptadecene.The contents of allthe chemical components were increased with the the increase of the populationdensity Sitophilus zeamais, The volatile contents were increased with the infestiontime by Sitophilus zeamais.The above research results illustrate the Sitophilus zeamais damage not onlyinfluences the rice main storage quality, but also influences the rice volatile mattervolatiles, so in the actual, according to several kinds of main storage quality changeand volatile matter content changes putatives Sitophilus zeamais damage and the ricestorage period.