全州 地方産 사과의 化學成分에 관한 硏究 : I.不揮發性 有機酸과 Pectin 含量의 變化에 관하여 I.Seasonal variation of non-volatile organic acid and pectin contents = Studies on the Chemical Composition of Apples in Jeonju District

다국어 초록 (Multilingual Abstract)

Eight varieties of apples were sampled periodically from Jeonju area during their growth and ripening and the change of the contents of non·volatile organic acids in the edible part and the change of contents of pectin in the peel were surrveyed. The results were summarized as follows:
1. Titlable acidity was high at the early stage of growing of fruit body leveling over one percent in Jonathan, Ralls and Bendavis. The acidity decreased gradually and at the matured stage it marked 0.40∼0.60 % in all the sample varieties except Indo. The titrable acidity of Indo was very low at about 0.2 % showing little change in its acidity.
2. Malic acid was the main non-volatile organic acid and was detected in all the sample varieties at every growing stage. Tartaric acid was detected in all the sample varieties at the middle growing stage. Oxalic acid was found in fully matured apples of Ralls, Golden and Fuji, and succinic acid was detected in Mclntosh red at its middle stage of growing but the contents of these organic acids were very low.
3. The content of pectin in the peel was high at the middle growing stage and was slightly low when fully ripened.