Study On Sugar Organic Acid And Phenolic Compounds Of Processing Apple Fruit

The 10 processing apple varieties and three table varietiesintroduced from France were studied. The indexes that sugars, organic acids,and polyphenol compounds (catechin, cafeoylquinique acid and ferulic acid)in apple fruits were related to processing qualities. Their contents,components and characteristics during fruit developing of were detected bycapillary electrophoresis technology and routine methods. The results wereas follows:1. As a new method, the capillary electrophoresis technology was applied toanalysis sugars, organic acids, and polyphenols in apple fruits successfully.2. The accumulation of sugars and organic acids in apple fruits were contrasted.In 2003, it was overcast and rainy for a long time. The data of sugar in 2003was lower than that in 2002 by 6~27%, and acids by 20~51%.3. In the same cultivating condition, the content of sugar was distinctlydifferent among different apple varieties. The content ranged from 7.8% to11.6%, while the content in DW is from 39.2% to 67.4%.4. There is significantly difference on acid content in different varieties, whichranged from 0.08 to 1.2%. The acid level in the table variety such as Dailuand bitter cider apple varieties such as Frequin rouge and Marie Menard arelower, under 0.25%, and moderate in the cider variety Douce Moet and juicevarieties such as Judestar, Jude line and Judaine are, while sour apple varietiessuch as Petit jaune, Avrolles, Jurella and Granny smith are very high, rangedfrom 0.79 to 1.20%.5. As the chief sugar in apple fruit, Fructose content changes from 361.2 to202.5 mg/g DW in examined varieties, and the proportions in differentvarieties were obviously different, ranged from 44 to 75%. glucose andsucrose take the proportion of 9~36% and 11~40%, respectively. The content and proportion of three kinds of sugar in different varieties 4山东农业大学硕士学位论文have greater difference. The content of fructose in Jude line is the highest,361.2 mg/g DW; taking up 54% of the total sugar; glucose content is alsohigher, taking up 31% of the total sugar, but sucrose take up 15%. Thesucrose content of Jude star reaches 25 mg/g DW, holding 40%, and is highestin the tested varieties, but the content of glucose take up 9% of total sugar only.The content of fructose in Dai Lu is higher relatively, but glucose is lower ,only taking up 14%;.The content of glucose in Granny were 36% and is higherthan other varieties The proportion of glucose and sucrose in Frequin rouge islow, only taking 12% and 13% respectively, but the fructose is the highest,which reaches to75%.6. The polyphenol content in different apple varieties has great differences,range from 3.35 to 25.4 mg/g DW. Contents of total polyphenol in GoldenDelicious and juicy varieties such as Jude line, Judaine and Judin are low; andall are under 4.5 mg/g DW; The total polyphenol contents in cider varietiesand sour apple are higher, 12~21.3 mg/g DW. The contents of 3 kinds of polyphenols are different in different varieties.Cafeoylquinique acid content in Granny is the highest; reaching 84% of thesum of 3 polyphenols, but no Cafeoylquinique acid was detected in Jude line.Ferulic acid content in Frequin rouge and Marie menard is the highest,reaching 1.585mg/gDW and 1.512mg/gDW, respectively. Catechin contentin Frequin rouge is the highest, reaching 1.716 mg/g DW.7. Our experiment also finds that the browning degree of pulp in differentvarieties is not significantly correlated to total polyphenol content, but iscorrelated to the catechin content. Frequin rouge, Marie menard and Dailuwith higher content of catechin are browning much faster, especially the tablevariety, Dai Lu, for the content of catechin takes up 90% of the sum of 3polyphenols, browned swiftly, though it has lower total polyphenol content.8. The color value of apple juice will be significantly rise during storage. Asantioxidant, Vitamin C has notable effect in inhibiting...