Effect of Thermal Processing on Lima Bean Vitamin B-6 Availability

Unit operations in lima bean processing were evaluated by their effects on the availability of vitamin B-6. Blanching of rehydrated lima beans resulted in the loss of about 20% of the pyridoxine. In the enzymic digests of the heat processed samples, pyridoxal and pyridoxal-5′-phosphate were not found in appreciable quantities. This was interpreted as a loss in availability, because the acid hydrolysates of both the processed and blanched samples showed a difference of only 15% in the pyridoxal content. This showed that although vitamin B-6 was destroyed only to a small extent during thermal processing, its availability was reduced by almost 50%.