Granule residues and 'ghosts' remaining after heating A-type barley-starch granules in water

Slow leaching and prolonged incubation at 50° of undamaged, large (A-type) barley-starch granules resulted in annealing of the residual granules with an increase in the gelatinisation temperature from 61° to 74°, and the residual granules still retained an ordered structure. The insoluble glucan ('ghosts') remaining after the starch granules were heated either slowly or instantaneously to 100° showed no evidence of order, contained mainly amylopectin, and were solubilised by alpha-amylase but not by protease. A comparison was made with the ghost-forming capabilities of starches from other sources. Slow teaching and prolonged incubation at 50° of undamaged, large (A-type) barley-starch granules resulted in annealing of the residual granules with an increase in the gelatinisation temperature from 61° to 74°, and the residual granules still retained an ordered structure. The insoluble glucan ('ghosts') remaining after the starch granules were heated either slowly or instantaneously to 100° showed no evidence of order, contained mainly amylopectin, and were solubilised by alpha-amylase but not by protease. A comparison was made with the ghost-forming capabilities of starches from other sources