Studies On The Effect And Mechanism Of Quality Improver On Apple Fruit

The apple cultivated area and total yield in China all rank the first in the world. But atpresent， the poor quality and weak fruit flavor become the main problem our country，which affect the ability of our country to participate in international competition. The fruitskin color is an important symbol of fruit ripening and the major limitations to fruit prices andsales. The application of bagging technology in large areas improved the surface smoothfinish and the skin color of apple effectively. But fruit bagging is bad for the accumulation ofsugar， acid， Vc and so on， which declines the quality of fruits obviously. Under the laborand production cost pressure， countries such as Japan， Europe and America have restoredno bag cultivation.This research was conducted to explore an apple fruit quality improver which is moreefficient and energy saving， safety and environmental protection， prepared with ediblefilm-forming ingredient which can improve fruit finish， the optimal concentration of themain component and salt-tolerate dispersing agent previously selected， and the apple growthessential nutritive elements. Through the determination of fruit intrinsic and appearancequality of early， middle， and late maturity apple cultivars， we explore the mechanism ofthe self-developed quality improver and the possibility of alternative to bagging. The resultsshowed:1. In the process of the screening test for edible film-forming ingredient， twofilm-forming substances CTS and CMC-Na showed good film forming ability. Theirfilm-forming liquid can be pervious to light， with good air permeability and water soluble，chitosan had some antibacterial effect also. The compound preparations used for apples andoranges， have a certain luster， and showed good film-forming effect and certainpermeability.2. Both TR1and TR2could increase the single weight， and Regular the shape index ofthe early and midlle maturity apple cultivars significantly. The apple quality improvers couldimprove the sugar acid ratio of three apple cultivars， the2-quality improver was better.Compared with the bagging contrast， The2-quality improver increased the Vc content of"Yuhuazaofu" and "Changfu2" by23.86%and23.86%; Compared with TCK， two kind ofquality improvers， especially the1--quality improver， increased the ratio of soluble solid content to titration acid of two apple cultivars significantly， and compared with the TCK，increased the fruit hardness of “Yuhuazaofu” by9.72%and8.56%respectively; The effect ofquality improvers on Ca content was in keeping with hardness.3Quality improvers had significant effects on fruit coloring of “Yuhuazaofu” and“Changfu2”. Its fruit coloring was close to TCK， but not so bright. TR1and TR2increasedthe a*value and reduced the L*value of “Yuhuazaofu” significantly; Two kinds of qualityimprover didn’t show the effect on the degradation of chlorophyll during the period of fruitgrowth， but by fruit maturity， TR1and TR2reduced the peel of chlorophyll significantly，and TR2increased the cyanine after spraying10days reached the significant level.4We discussed the mechanism of quality improver on promotion of apple fruitcoloration. Two kinds of quality improver promoted the fruit coloring of “Yuhuazaofu”mainlyby accumulating the anthocyanin， and reducing the chlorophyll at the same time; Increasingof the ratio of TSS to total acid after3times sprying provided adequate source of sugar to thesynthesis of anthocyanin. As the key enzyme of anthocynin synthesis， PAL also increased bythe increasing of anthocyanin.