Starch properties of native proso millet (Panicum miliaceum L.).

Abstract

Proso millet (Panicum miliaceum L.) starches extracted from three varieties ('Andongjaerae', 'Danyangjaerae' and 'Andong 48ho') have been studied. Amylose content ranged between 1.2 and 21.5%. Starch content was from 84.4 to 85.67%. The onset temperature (To) of all starches ranged from 73.1 to 76.4 °C, peak temperature (Tp) ranged 78.0 to 81.5 °C, and their gelatinization enthalpy varied from -0.81 to -4.48 J g -1 , respectively. The highest peak, highest breakdown, very high final viscosity, and very low setback were noted in 'Danyangjaerae'. X-ray diffraction angles showed in all starch granules possessing a typical A- type crystallinity, exhibiting strong deflections at about 15° 2θ, an unresolved double at 17°, 18° 2θ and separated angle 23° 2θ. The degree of crystallinity was higher in 'Andong 48ho' than in 'Andongjaerae' and 'Danyangjaerae'. A highly negative correlation was obtained between setback viscosity and relative crystallinity (r = 0.987, p < 0.01) with the amylose content and relative crystallinity (r = 0.964, p < 0.01). Positive correlation was observed between amylose content and setback viscosity (r = 0.869, p < 0.01).