Postharvest induced changes in sweet potato quality

Abstract

The effects of storage systems on sweet potato quality were studied. A double-walled plastic greenhouse-like structure with outside air exchange proved to be a very good alternative to large, expensive commerical storage complexes. There were no significant differences noted for intercellular space or specific gravity due to storage treatment. These are important indicators of storage loss. No significant differences were noted for Gardner "L", "a" and "b" color values, ascorbic acid and carotene in the stored sweet potatoes. The protein content of the commercially stored potatoes was significantly lower than those stored in the greenhouse-type structure. Total sugars increased in storage while total starch decreased. The potatoes stored near the top in the greenhouse-like structure exhibited a lower total sugar content. In the canned samples there was a significant loss of firmness throughout the storage period. No differences in firmness were noted between treatments. After canning, there were significant losses in Gardner "L" (lightness) color, "a" (redness) color, ascorbic acid, and protein. Increases were noted for the total solids, "b" (yellowness) color, total sugar, total starch and soluble solids. Sensory panelists preferred the color of sweet potatoes stored in the bottom layer of the greenhouse. No differences were noted for other sensory qualities.