Effects of varieties, curing of tubers and extraction methods on functional characteristics of potato starch

The investigation was conducted to study the effects of variations in quality and functional properties of starch isolated from fresh and cured tubers of potato, different varieties and extraction methods. The starch was extracted from four white flesh varieties (Kufri Chipsona-4, Kufri Badshah, Kufri Pushkar, Kufri Bahar) and one pink flesh variety (Kufri Sindhuri). Among the different starch extraction methods tried, the results have been reported for water extraction method (control) and combined method (extraction with ambient water 30 degrees C + 0.25% NaOH + 2% SDS-ME + 5.25% NaOCl + 0.15% cellulase enzyme). The starch extracted was analysed for its quality and functional characteristics. Starch extracted from potato variety Kufri Chipsona-4 showed higher water absorption capacity (258%), swelling power (38.4 g/g), solubility (35.8%) and light transmittance (22.7%) as compared to other varieties. Syneresis was minimum in the starch of Kufri Pushkar (20.3%) followed by Kufri Bahar (22.5%), Kufri Sindhuri (35.6%), Kufri Badshah (41.7%) and it was maximum in Kufri Chipsona-4 (47.8%). For all the varieties, curing of tubers resulted in lower yield, amylose content, swelling power and solubility; but higher amylopectin, phosphorus, WAC and light transmittance of extracted starch. The combined method of starch extraction was found better than control, as the starch extracted had higher yield, amylopectin content, water absorption capacity, swelling power, solubility and light transmittance.