Physicochemical and Technofunctional Comparison of Starch from Varieties of Native Potato (Solanum Phureja) with Commercial Starches

Abstract

Due to the high genetic variability of the potato, the starch can exhibit different properties of interest to the industry. With the present investigation, it is intended to know these differentiating characteristics in comparison with commercial sources that can be useful in different sectors. Therefore, the objective of this research was to establish a comparison between potato starches extracted from native varieties (Solanum phureja) with commercial potato and corn starches. A physicochemical analysis was carried out, for which characteristics such as amylose content, phosphorus, resistant starch (RS), slow digestibility starch (SDS), rapid digestibility starch (RDS), granule shape, granule size and crystallinity were evaluated. The technofunctional analysis included variables such as amylographic, thermogravimetric and differential scanning calorimetry analysis. The starches of the native varieties exhibited differential characteristics with respect to the commercial starches. Andina variety obtained the highest peak viscosity (8714 cP), followed by Ratona Blanca starch (6148 cP). In addition, these two varieties had the highest content of resistant starch (33.14±0.8) % and (28.9±0.7) % respectively), higher content of amylose (33.9 % and 35.5 % respectively), phosphorus (>0,08 % for both varieties), high crystallinity and higher enthalpy values (> 19 J/g for both varieties), which make them materials of potential use in different industries. The correlations presented between variables such as resistant starch (RS), enthalpy and crystallinity, showed possible differences at the structural level, which highlighted the differential characteristics of each starch.

Keywords

• amylose
• amylographs
• x-ray diffraction
• digestibility
• thermal properties