Effect of long-term storage on cell wall neutral sugars and galacturonic acid of two sweetpotato cultivars.
William M. Walter, Jr. and Cheryl S. Palma
Journal of agricultural and food chemistry. Volume 44, Number 1, Jan 1996. Pages 278-281.
1996
บทคัดย่อ
Jewel and Beauregard sweetpotatoes were sampled at harvest and after 49, 119, and 217 days of storage. At each sampling date for each cultivar, the concentrations of galacturonic acid (GA), galacturonic methyl esters, and cell wall neutral sugars were determined for both water-soluble and water-insoluble cell wall substances. For both cultivars, the GA content of water-soluble materials increased during storage, but the GA content of water-insoluble substances decreased, reflecting decreases in pectin size. The percent methyl ester content did not change for either cultivar. Cell wall neutral sugar concentrations declined in the order glucose much greater than galactose > xylose > rhamnose > mannose > arabinose > fucose. Changes in cell wall neutral sugars were minimal and were not observed in both cultivars. For both cultivars, the few cell wall sugar changes that occurred over time were best fit to a quadratic model. Thus, the only observed change in cell wall components that is known to affect firmness was the decrease in water-insoluble pectic substances and concurrent increase in water-soluble pectic substances.