Comparative analyses of the starch quality isolated from a local red potato and a commercial non-pigmented potato cultivar

A local cultivar of red potato vernacularly known as Badami alu with red pigmented tubers is known to be growing in the pockets of North-East India. The commercial value of the tubers has not been explored yet except for being consumed by the local people. In this context, isolation and characterization of starch from the local cultivar could increase its proposition to be used in the food industry. Comparative analysis with a commercially valued cultivar showed that a relatively higher amount of starch could be isolated from Badami alu which also possesses several unique features that could be instrumental in establishing its commercial value. Red potato starch was characterized by smaller granule size, lower amount of protein, free fatty acid, reducing sugar and amylose content. The crude starch also exhibited the presence of a significant amount of phenol which might be responsible for its antioxidative property. Higher water absorption capacity (WAC), oil absorption capacity (OAC), swelling power, solubility, paste clarity and least gelation concentration (LGC) also confers desirable attributes for its use in the food industry. Moreover, higher peak viscosity and breakdown viscosity values of red potato starch indicate better digestibility and improved resistance to external stresses like heating or stirring. All the above-mentioned properties indicated the superior quality of red potato starch over the white potato starch that present the promise of this local cultivar as a source of good quality starch for industrial application.