STARCH CHARACTERISTICS AND CANNING QUALITY OF 4 SELECTED NAVY BEAN (PHASEOLUS-VULGARIS) CULTIVARS

Starch of selected navy beans (C-20, Seafarer, Fleetwood and Breeding line 84004) was isolated and studied for its physico-chemical properti es. SEM was used to follow the morphological changes of starch granule s cooked at various temperatures (70,80,90-degrees-C). Among studied b eans, Seafarer starch exhibited weaker granule integrity. Upon heating , its granule remnants (mainly amylopectin) showed a greater degree of self-disintegration and capability to form matrix with the leached ou t materials (mainly amylose); hence resulting in more viscous paste an d firmer gel formation. Variations observed among bean starches cannot fully explain their differential canned bean texture and drained weig ht. Other structural/compositional components may play a greater role than starch in regulating these canned bean quality traits.