Abstract
It is known that pectic substances are hetero polysaccharides constituted with several kinds of neutral sugars besides galacturonic acid.
For the purpose of obtaining basal information on the suitability for cooking and processing of pectic substances, we examined constituent sugars of pectic substances extracted from 20 kinds of fresh fruits and those of 4 kinds of commercial pectin.
The contents of anhydrogalacturonic acid in the pectic substances from fruits were 26.2% in banana pulp, 36.9% in banana peel, 38.8% in loquat and 39.8% in Japanese persimmon, while those from the other fruits were 50.4 to 74.7%.
The fractionation of neutral sugars by liquid chromatography showed that the amounts of neutral sugars contained in each pectic substances were variable, but their kinds are almost similar. Arabinose or galactose was the largest in amount. The next largest ones were rhamnose and xylose. Mannose was very small in amount and the ribose amount was a trace. No constant result was obtained with glucose.
