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Cooking time is an important trait in the breeding of common beans (Phaseolus vulgaris L.), especially in Mexico where 96% of beans consumed are prepared in the household. Because of the characteristics of the cooking time trait, a method of indirect selection would increase selection efficiency. The objective of this study was to identify random amplified polymorphic DNA (RAPD) markers associated with the trait and estimate genetic parameters of cooking time. For that purpose, 104 recombinant inbred lines (RILs), derived from contrasting cooking time bean cultivars were evaluated for three consecutive generations (F5 to F8). In each generation, cooking time was determined and plants in the F7 generation were genotyped. One marker was associated with cooking time. The polymorphic UNAM‐16 of 310 base pairs (bp) explained 23% of the variation in cooking time of the lines studied. Narrow sense heritability (h2) was estimated for cooking time, as was the number of genes involved in the trait. A high value of h2 (0.74) was estimated for cooking time. Also, it was estimated that two genes control the cooking time trait.

Pectic cell wall enzymes are responsible for the changes in rhamnogalacturonan I and polygalacturonan induced during soaking and constitute the biochemical factors that give bean cell walls new polysaccharide arrangements. Rhamnogalacturonan I is dispersed throughout the entire cell wall and interacts with cellulose and hemicellulose fibres, resulting in a higher rate of pectic polysaccharide thermosolubility and, therefore, a shorter cooking time.

The present results suggest the use of spoiled bean seeds, e.g. anthracnose-damaged beans, as an alternative for the isolation of ACE-I-inhibitory peptides to be further introduced as active ingredients in functional foods.