Research On Quality Characteristics And Keeping-fresh Technics Of Fresh Corn

In order to find the key factor of quality of fresh corn, variety rule of quality of fresh period and keeping fresh mechanism . Two types maize were carried out in the corn research garden of Shandong Agriculture University. The physiological index and ultrastructure was mensurated . The result was as follows:1. The key factor of quality of fresh cornThere were differences between sweet corn and waxy corn. Sweet corn had high soluble sugar content and waxy corn had high amylopectin content. They had different key factors and should be separated when appraising. Pericarp thickness, amylose content, amylopectin content, amylum content soluble sugar content and pasting properties were the key factors . Amylum of sweet corn was low, but the other key factor of sweet corn showed better . Sweet corn had high water content, so the quantity of fact was low .The grain color associated with lots of degustation factors. The quality of yellow fresh corn showed the worst . They had thick pericarp, low level of soluble sugar content and amylum content, worse pasting properties . Tassel of purple corn were smaller than another color's, but had better edible and nutrition qualities . The diversity of white corn was the biggest . Jingpoyinnuo, Zhunuo5 were the best and could be popularize fargoing .2. Variety rule of quality of fresh periodThe trend of variety of quality of fresh period of fresh corn was up first and down then . Degustation score ascended and nutrition level descended in the prophase of fresh period . Degustation score and nutrition level descended in the anaphase of fresh period . The reasons was as follows: 1.Tenacity of pericarp became greater . 2. Water content descended . Starch plastid became bigger , and the amylum content was too high . 3. Soluble sugar content descended, and pasting property became worse .Protein body became more in the fresh period of fresh corn, Starch plastids of Lunuo6, Jingpoyinnuo were big and brimming . Starch plastids of Jinhui55 became more but small . It was the reason why the amylum content of Jinhui55 was low.3. The infection of two processes to the quality of fresh cornThe reasons of the infection of two processes and storage time to the quality of fresh corn is different . Poach made soluble sugar and soluble protein dissolve in water , going with the content descended . Vacuumizing would not appeared such condition.After storage 100 days, the edible quality of poach corn became worse, while vacuumizing made better . the trend of variety of soluble sugar content and amylum content were same . Pasting properties of poach waxy corn descend massly . Infection to vacuumizing was little .Pasting properties may be the key factor of storage quality .