Changes in the physico chemical properties of peach fruit pectin during on tree ripening and storage英文电子书.pdfVIP

J. AMER . Soc. HORT . SCI. 118(3):343-349. 1993. Changes in the Physico-chemical Properties of Peach Fruit Pectin during On-tree Ripening and Storage 1 2 3 M.L. Fishman , B. Levaj , and D. Gillespie U.S. Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, 600 East Mermaid Lane, Philadelphia, PA 19118 R. Scorza4 U.S. Department of Agriculture, Agricultural Research Service, Appalachian Fruit Research Station, 45 Whitshire Road, Kearneysville, WV 25430 Additional index words. Prunus persica, intrinsic viscosity, molecular weight, radius of gyration, high performance size exclusion chromatography, cell walls Abstract. Radius of gyration (size), intrinsic viscosity, molecular weight, percentage of galacturonate, and percentage of neutral sugars were measured for chelate-soluble (CSP) and alkaline-soluble (ASP) pectins extracted from the cell walls of melting flesh (MF) and nonmelting flesh (NMF) peach [Prunus persica (L.) Batsch]. Weight percentage of cell walls, pectin content, and firmness were measured also. Peaches were extracted at 20, 21, and 22 weeks after flowering (WAF) and after various lengths of shelf storage at 25 ± 2C for the peaches picked at 21 WAF. Weight percentage of cell walls and firmness decreased markedly between the 21st and 22nd WAF; and between the 3rd and 6th day of storage for MF peaches as compared to NMF peaches. During these same periods, there were marked drops in the pectin content and the uronide content for M