Starch 56 : 570-575 (2004)

Reversible regulation of the gelatinization behavior of potato starch with poly(lysine) and amino acids

W. Yang, M. Hattori, T. Kawaguchi, and K. Takahashi

Poly(lysine) (PL), lysine (Lys), monosodium glutamate (GluNa), glycine (Gly), alanine (Ala), and leucine (Leu) were used to regulate the characteristic gelatinization behavior of potato starch. PL, Lys, and GluNa with a positive or negative net charge elevated the gelatinization temperature evaluated by differential scanning calorimetry with increasing amount added as compared with the small effect of Gly, Ala, and Leu with zero net charge. The peak viscosity evaluated by a rapid viscoanalyzer was markedly decreased by adding PL, Lys, and Glu, whereas Gly, and Ala had no effect on the peak viscosity. The swelling power was also decreased by added PL, Lys, and GluNa, whereas it was unchanged by added Gly, Ala, and Leu. Potato starch immersed in PL and amino acids solutions released the most retained PL and amino acids by the subsequent washing with water. The increased gelatinization temperature of the PL-treated potato starch returned to the original value by washing with water. It is thus considered that the regulatory effects of PL and amino acids on the gelatinization behavior of potato starch were substantially reversible.