| Carya illinoensis(Wangerm.) K.Koch known as the pecan, its kernel tastes beautifully and hasgreat nutritive. The fat content of pecan is high, which causes the quality decline owing to rancidityduring the storage. The study of pecan is more about breeding and cultivation than the storage in thedomestic. This paper studied the effects of different kernel and different storage temperature anddifferent MAP on physiology and quality of pecan, in order to prove the fat oxidation mechanism andthe appropriate pretreatment method and storage technology.Frist, Effects of Voluntary Modified Atmosphere Packaging (MAP) on Physiology andQuality of Pecan at cold storage and Room Temperaturethe physiology and quality of pecan under modified atmosphere packaging,Which were cased in30μm yellow PVC bag,30μm white PE bag,50μm white PE bag and woven bag at room temperatureand cold storage were studied. The result showed that relatively low O2and high CO2storage by30μmyellow PVC bag,30μm white PE bag,50μm white PE bag, especially50μm white PE bag were betterthan woven bag. the respiratory rate, AV, POV, saponification value of50μm white PE bag were thelowest, and the total fat content, iodine value, unsaturated fatty acid, γ-VE of50μm white PE bag werethe highest. the respiratory rate, AV, POV, saponification value of woven bag were the highest, and thetotal fat content, iodine value, unsaturated fatty acid, γ-VE of woven bag were the lowest. So the MAPwas preferable to maintain the quality of pecan than woven bag, especially the50μm white PE bag at atroom temperature and cold storage.Second, Study of Fatty Acid Oxidation of Pecan kernel with or without Shell at Cold Storageand Room TemperatureIn this article, the oxidative changes of fatty acid of unshelled pecan at American, half kernel andfragmentized kernel of shell-less pecan which were cased white40μm polyethylene plastic bag at4temperature and room temperature were study. Results of the study confirm that total fat,γ-VE,Unsaturated fatty acid and Iodine value of pecan dropped and their AV. POV. saponification value roseduring storage. It was showed that oxidation of fat acid of pecan kernel were restrained by shell and itwas advantageous to their storage quality. Throughout150days storage at4temperature. Storagequality of unshelled pecan kernel was better than that of half kernel and fragmentized kernel of shell-less pecan at room temperature and cold storage.The last, Effect of different temperature on the fatty acid of pecanThe experiment selected pecan as experimental materials. In order to study the effect of differentstorage temperatures on fatty acid of pecan, which were storage at room temperature(20-30℃),4℃.Theresult showed that: total fat, Unsaturated fatty acid and γ-VE, Iodine value of pecan of roomtemperature(20-30℃) storage dropped faster than4℃storage and their AV. POV. saponification valueof room temperature(20-30℃) storage rose faster than4℃storage. therefore, the quality of pecanstored under4℃is better than room temperature(20-30℃). |
