Starch Characteristics, Sugars and Thermal Properties of Processing Potato ( Solanum tuberosum L.) Cultivars Developed in Korea

Seven processing potato ( Solanum tuberosum L.) cultivars were evaluated for biochemical properties, starch morphology, crystallinity and thermal properties. One-way ANOVA results indicated a significant difference in those quality properties of individual potato cultivar. Dry-matter, total starch, and reducing sugar contents were ranged in 21.34 ~ 24.88%, 15.6 ~ 18.3%, and 0.24 ~ 1.09%, respectively. Glucose and fructose contents were ranged in 1.03 ~ 5.28% and 0.59 ~ 3.69 mg/g DW, respectively. Saebong, a round-oval shape with white-fleshed potato cultivar, was higher in dry-matter and total starch contents. The cultivars of Atlantic, Jinseon, and Saebong showed lower reducing sugar contents ranged in 0.24 ~ 0.27 mg/g DW. The extracted potato starches showed a similar morphology, which was round, oval or elliptical shape with mixed sizes of large, medium and small starch granules and glossy surface with regular pattern. The X-ray diffraction patterns were a typical B-type, which was generally observed in root plants. The major crystallinity peaks were at 5.5°, 14°, 17°, 19°, and 22° in 2 Ɵ . There was a positive correlation between the onset temperature (To) with dry-matter and total contents, but a negative correlation with reducing sugar, glucose and fructose contents. The variations in physicochemical and starch properties of different potato cultivars could be directly related to the use of potato, which make them useful for industrial application.