Isolation and Characterization of Non‐Conventional and Underutilized Starch from Water Lily (Nymphaea lotus): Functional, Rheological, and Thermal Properties

Abstract

In this study, starch is isolated from Nymphaea lotus and its functional, rheological, and thermal properties are compared with potatoes, rice, and maize starches. The swelling power and solubility of all starches increased as the temperature increased. After 5 days of storage at +4 °C, syneresis increased, but paste clarity is decreased. The Herschel–Bulkley model well described the flow behavior, as evidenced by the upward and downward curves’ R2 values are higher than 0.95. Storage modulus and loss modulus increased as frequency increased, and the loss factors is less than unity for all starches. Differentially scanning calorimeter thermograms show the onset, peak, and conclusion temperature ranged from 58.5 to 68.01 °C, 68.94–73.97 °C, and 79.6–88.77 °C, respectively. The gelatinization temperature range and enthalpy of gelatinization ranged from 14.0 to 21.1 °C and 9.40–13.35 J g−1, respectively. Starch from N. lotus rhizome and seed exhibited a higher gelatinization temperature than potato starch, whereas their enthalpy of gelatinization is lower. Overall, the present finding will promote the utilization of starches isolated from the rhizome and seed of N. lotus for food and non‐food industries.