Differences in hollow volumes in cooked rice grains with various amylose contents as determined by NMR micro imaging

The presence of hollows in cooked rice grains found before in the cultivar Koshihikari was confirmed for 4 more cultivars with various amylose content s. The size, shape, and total volume of hollows differed between cultivars. Hollow volumes increased with grain volume and length before 100 degrees C was reached, but subsequently decreased during prolonged boiling. The prev iously proposed mechanism, describing sealing by gelatinized starch of crac ks formed during soaking, seemed accurate for all 5 cultivars. Based on the hypothetical model of their formation, a relationship between amylose cont ent and hollow formation was assumed. However, no correlation existed betwe en final hollow volume and shape on 1 side and individual parameters such a s flour gelatinization and amylose content on the other side.