Study On The Pest Control Of Wheat Noodles From Kazakhstan

As a semi-finished product of wheat flour industrialized processing,noodles are popular convenient noodles for people in the north and south of China.At present,there are Kazakstan wheat production of noodles on the market,the product flavor and taste is excellent,is the high-end products of noodles.However,the products are susceptible to the infection of stored grain pests during the storage and circulation process.This paper compared the susceptibility of wheat noodles produced in Kazakhstan with that produced in China,and analyzed the reasons for the difference of susceptibility.In this paper,the condition parameters of the adult of Tribolium castaneum and Oryzaephilus surinamensis in the dried noodles produced by the ozone fumigation of wheat in Kazakhstan,and the quality changes of ozone fumigation in Kazakhstan wheat noodles were analyzed.The susceptibility test of dried noodles made from Kazakhstan showed that under the condition of starvation for 12 h and trapping for 8 h,O.surinamensis had the most significant selectivity for Kazakhstan original noodles（44.38%）.T.castaneum had the most significant selectivity（53.13%）,under the condition of starvation for 16 h and trapping for 10 h.Three kinds of dried noodles types and concentration of volatile substances were different.The high concentration of 1-octene-3-alcohol and pentanal in the Kazakhstan original noodles may be the main flavor sources which Kazakhstan original noodles attracted T.castaneum and O.surinamensis.The special flavor of corn in Kazakhstan maize flavor noodles reduces the selectivity of two pests.After 120 min fumigation with ozone concentration of 170 mg/m³,all the adults of O.surinamensis and more than 90%of the adults of T.castaneum could be killed.LT₅₀and LT₉₉values of O.surinamensis of 170 mg/m³ozone fumigation were 0.51（0.46～0.56）h and 2.36（1.89～3.17）h for 170 mg/m³ozone fumigation,respectively.T.castaneum LT₅₀and LT₉₉values of T.castaneumof 170mg/m³ozone fumigation were 0.42（0.36～0.48）h and 1.36（1.10～1.84）h,respectively.The values of T.castaneumwere different from the measured values.There may be some individuals in the natural population of T.castaneum who are tolerant to low-dose ozone for a long time.Therefore,when using low dose ozone to fumigate noodles to kill insects,the lowest effective fumigation time test should be carried out on the pests in the environment first to avoid fumigation failure.Different fumigation duration of 170 mg/m³ozone on the Kazakhstan original noodles lead to different composition of volatile substances in the noodles.After 5 days of fumigation,the composition of alcohols and aldehydes in the noodles reached a stable state.After the fumigation,the types and contents of aldehydes in the noodles increased,while the alcohols decreased.T.castaneum had no significant difference in the selection rate of the noodles fumigated with 170 mg/m³ozone for 120 min compared with that without fumigation,but O.surinamensis selection rate of the fumigation noodles was significantly higher than that of the control.This may be due to the increase of（E）-octenal,2-heptanone,1-octene-3-ol and valeraldehyde in the noodles after ozone fumigation.The results showed that the low dose ozone fumigation could kill the pest infection of the noodles,but it could not reduce the risk of re-infection of the noodles during circulation and storage.Moreover,the tight packaging of noodles is very important to prevent insects.There was no significant change in the quality of the Kazakhstan original noodles fumigated with 170 mg/m³ozone for 50,60 and 120 min,respectively.With the extension of fumigation time,the moisture loss in the noodles was greater.After 120 min of fumigation,the moisture content in the noodles decreased by 1.3%.After fumigation,the cooking loss rate of the noodles decreased,and the optimal cooking time remained unchanged,which was 6 min.The quality of the noodles after ozone fumigation at different time was analyzed by using texture analyzer.Compared with the control group,there were no significant differences in the hardness,adhesion,elasticity,adhesion,masticability and resilience of the noodles after ozone fumigation for 50 min.The hardness of noodles increased significantly,but the adhesion decreased significantly,after 60 and120 min of fumigation.Based on the results of this study,the authors put forward some technical suggestions on controlling pests by ozone in Kazakhstan original noodles.The freshly produced noodles were fumigated with 170 mg/m³ozone for 120～240 min before packaging.It is suggested that paper-wrapped and simple-wrapped products should be packed in large quantities with good airtight materials and unpacked in large quantities after entering the retail chain,which can minimize the risk of pest infection before the products reach consumers.