Nutritional composition and cooking characteristics of tepary bean (Phaseolus acutifolius Gray) in comparison with common bean (Phaseolus vulgaris L.)

Abstract

Tepary bean is a highly abiotic stress tolerant orphan crop for which there has been limited research on its nutritional value and cooking characteristics. These are key aspects when considering the potential for broader adoption of tepary bean. Therefore, the goal of this study was to evaluate a large set of seed composition and cooking traits related to human nutrition using both landraces and breeding lines of domesticated tepary bean from replicated field trials and to compare the traits in tepary with those in common bean. Tepary bean showed reduced fat and ash concentration and higher sucrose concentration as compared to common bean. Of the twelve amino acids evaluated, only proline in one of the two trials was statistically different between the two species. There were statistically significant differences between tepary and common bean for the concentration of some elements in this study; however, the elemental concentrations fell within the range of those found for common bean in previous studies. The majority of tepary bean lines showed consistently short cooking times and a high percentage of seeds showed measurable water uptake, while some showed a hardshell trait (low water uptake) and longer cooking times. Principal component analysis on a subset of traits showed a distinct group of common beans and two tepary bean groups that were divided on the basis of several agronomic, cooking, and elemental composition traits. Tepary bean, as with other pulses, is a highly nutritious crop with the range of composition and cooking characteristics similar to those of common bean. The variability for seed composition and cooking traits found within tepary bean can be exploited for its improvement.