Characterization of Starch from Two Andean Potatoes: Ccompis (Solanum tuberosum spp. andigena) and Huayro (Solanum x chaucha)

Starches from two Andean potatoes, Ccompis (Solanum tuberosum spp. andigena) and Huayro (Solanum x chaucha), are characterized and compared to commercial starches by scanning electron microscopy (SEM), measurement of amylose content, rotational viscometry (2% starch solution), Rapid Visco Analyzer (RVA) (5% starch paste), and texture analysis (8% starch gel). Ccompis and Huayro starch granules are similar in appearance to commercial potato, while the apparent amylose content is higher in Ccompis (32%), followed by commercial potato (27%), Huayro, and corn (24%). The rheological properties of Huayro starch and that of commercial potato are similar, as measured by three rheological techniques. However, Huayro does not show any significant peak viscosity in RVA analysis but has a higher final (setback) viscosity. On the other hand, Ccompis starch solutions consistently exhibit lower viscosities and form weaker gels compared to commercial potato starch. All potato starch (2%) solutions show dramatic viscosity breakdown when subjected to the various treatments including acidification, high temperature, and shear.