Physiochemical, Pasting, and Thermal Properties of Starch Isolated from Different Barley Cultivars

Starches from eight different barley cultivars were isolated and evaluated for their physiochemical, thermal, and pasting properties. The amylose content varied significantly among cultivars and ranged from 21.0 to 28.3%. The majority of the starch granules were of the B-type (20 to 40 μm) in size and accounted for 50.5 to 61.6% of the total granules. The starch gel from RD-2052 showed the highest firmness (0.55 N). The pasting behavior of starch varied significantly; the PL-172 cultivar showed the highest peak viscosity (2622 cP) while it was lowest for RD-2035 (1913cP). The time to peak of pasting properties exhibited a significant (p ≤ 0.05) negative correlation with water solubility index (r = −0.74). The pasting temperature showed a significant (p ≤ 0.05) positive correlation with water binding capacity (r = 0.73) and significant negative correlation with water solubility index (r = −0.82). The highest enthalpy of gelatinization (ΔH) was exhibited by DWR-28 cultivar (4.9 J/g). Amylose content showed a significant (p ≤ 0.01) negative correlation with ΔH (r = −0.90). A significant (p ≤ 0.01) positive correlation was observed between gelatinization temperature range and water binding capacity of starch (r = 0.85).