Compositional, morphological, structural and physicochemical properties of starches from seven naked barley cultivars grown in China

- Properties of starch granules from seven naked barley cultivars have been investigated.
- Similar granule shapes and crystalline structure of various starches have been observed.
- Significant differences in properties among various starches have been found.
- The results provide a basement on the applications of naked barley starches.

Starches from seven naked barley cultivars in China were isolated and investigated for their compositional, structural and physicochemical properties. The range of starch purity, lipid, protein, amylose and amylopectin contents and the amylose/amylopectin ratio for different varieties were 90.58% to 97.95%, 0.01% to 0.02%, 0.31% to 0.45%, 22.72% to 27.49%, 65.89% to 72.64% and 0.31 to 0.39, respectively. The starches from all naked barley cultivars exhibited A-type crystalline packing arrangements and similar granule shapes. The rapid visco analyzer (RVA) results showed the peak viscosity, trough viscosity, breakdown, final viscosity, setback, peak time and pasting temperature of starches ranged from 2977 to 3641 cP, 2253 to 2844 cP, 474 to 876 cP, 3094 to 4320 cP, and 729 to 1476 cP, 5.53 to 6.80 min and 50.25 to 84.35 °C, respectively. The transition temperatures (To, Tp and Tc), gelatinization temperature range (ΔTr) and enthalpies of gelatinization (ΔH) measured using a differential scanning calorimeter analyzer (DSC) ranged from 54.07 to 58.47 °C, 57.51 to 61.54 °C, 65.49 to 72.74 °C, and 10.46 to 16.58 °C and 7.74 to 9.82 J/g, respectively. The various structural and physicochemical properties demonstrated by naked barley starch suggest their broader potential applications of this novel cereal.