부산대학교 도서관

The root and tuber crops contain pectin substances and parenchyma cells (PC). Starch granules are surrounded by intact PC. When food make with PC, it plays a barrier roll and a resistant starch for low GI level foods to prevent heart diseases and diabetes. Although potato and sweet potato flours have been well-studied, physicochemical properties of PC have not been extensively studied. The objectives of the present study were to understand the physico-chemical properties of PC and to compare potato and sweet potato flours for future use in food industry. The moisture content of sweet potato parenchyma cell (SPC) was lower than potato parenchyma cell (PPC). PPC (13.16%) showed higher non-starch polysaccharide contents than SPC (11.03%). Both SPC and PPC showed lower ash, crude protein and crude fat contents than those of flours because when samples were washed away during the isolation of PC. Starch granules and PC of potato were bigger than those of sweet potato. Starch granules existed in PC intact, while they were leaked out in flour from PC due to disintegration of PC. In DSC, amylopectin melting enthalpy of PPC (12.56 J/g) was higher than SPC (9.84 J/g). Solubility of PPC and SPC did not differ significantly, but those of flours were much lower than PC. Moreover, PC inhibits pasting of starch granules. These results indicate that PC plays a barrier roll to prevent the water absorption and heat penetration. In the result, in vitro digestibility parenchyma cell can not help reduce GI level. Consequently, PC of potato and sweet potato could be used in food industry as a low GI ingredients.