The Research On The Properties Of Starch And Browning Of Different Varieties Of Potatoes At Different Growing Stages

China is the largest potato production country in the world both in growing area and production. Potatoes are planted widely in China. The major regions lie in the northern cold regions (including northeast, north and northwest territories of China) where accounting for 50% of the total potato in China. As the development of potato starch and food processing industry, the need of varieties with high and good quality of starch is compelled. However, the fundamental research of potato processing characteristics was comprehensive. At present, the local main cultivars which starch contents are in the middle level are always used to produce starch. Cultivars for starch processing and specific purpose suitable for market were mature. Meanwhile the appearance, starch content and main quality characteristics are different under different ecological conditions, so study and analyse on every target of potato can provide basic data and theory for farmers and processing enterprises.In this study,16 varieties of potatoes selected at four different growth stages, whose appearance characteristics, crystal structure of starch granules, starch content, profile browning, starch gelatinization were measured. And the data were statistical analysised with variance and multiple comparison and correlation analysis by Excell. The results were indicated as following:(1) There were different characteristics of appearance of potato in different growth stage. There existed significant differences of the size of potato tubers, the number of buds per unit area of cultivars at different growth stages. Meanwile, the colors and the appearances of potato were also influenced by growing conditions and varieties.(2) The shape of potato starch granules is oval and the starch grains are larger with the extended growth period.(3) There was a very significant difference in different varieties of potato starch. Atlantic has the highest starch content of the16 varieties, Tongshu NO.20 of the lowest. The growth stages have significant impact on the starch content. The potato starch content increasedwith the extended growth stages.(4) Potato varieties and growth stages on the profile of the browning has a very significant impact. The harvest potato's browning is intensity than the potato at growth stages. With the growth period of the extension, browning increased. At the same time. The browning of potato profile has highly significant correlation with the time exposed to the air.(5) The potato starch gelatinization temperatures were between 57-69℃of 16 varieties. The highest peak viscosity is LK99, followed by DingXuan No.1.