Dry beans (Phaseolus vulgaris L) are a nutrient dense, low cost food and therefore are an excellent value for consumers (Drewnowski and Rehm, 2013). In spite of this value, long cooking times limit bean consumption. This is true in developing countries where cooking fuel is sometimes scarce and in developed countries where consumers don’t have time to invest in cooking (Brouwer. et al. 1989). Understanding the genetic variability for cooking time in beans would help efficiently breed fast cooking bean varieties. The objective of this study was to evaluate the cooking time of a panel of Andean bean lines from diverse market classes and seed types important in major bean growing and consuming regions of Africa and the Americas.

Modified Mattson-type cooker (left). Technician measuring cooking times (right)

Materials and Methods: A subset of 250 bean lines of the Andean Diversity Panel (ADP) was grown in 2012 at the Montcalm Research Farm in Entrican, MI. Two replications were planted per entry in a randomized complete block design. The cooking time of each entry was then determined using a modified Mattson-type cooker (Mattson 1946) on 25 pre-soaked bean seeds in DI water for 12 hrs. Weight differences between raw and soaked seeds were measured to determine water uptake. The optimum cooking time was recorded as the time it takes for 80% of the plungers to pierce the seeds (Wang, 2005).

Figure1: Range in cooking time of 250 bean genotypes grouped by seed type. Numbers in parentheses represent how many of genotypes in each market class. The black line in each bar indicates the mean cooking time of the samples.

Results and Discussion: Cooking data was collected on 250 bean genotypes representing diverse Andean germplasm from eight major market classes. The cooking time ranged from 17 min to 90 min and the fastest and slowest cooking beans were both cranberry types (Figure 1). As a group, the white beans were the fastest cooking and also had the least amount of diversity for range of cooking time. This diversity analysis will be useful to identify parental materials, to understand the genetics control of cooking time, and to breed fast cooking beans in diverse Andean market classes.

References: Brouwer I. et al. 1989. Nutritional impacts of an increasing fuelwood shortage in rural households in developing countries. Progress Food Nutr. Sci13:349-361.

Drewnowski A, Rehm C. 2013 Vegetable Cost Metrics Show That Potatoes and Beans Provide Most Nutrients Per Penny. PLoS One 8(5): e63277.

Mattson S. 1946. The cookability of yellow peas. Acta Agric Scand 2: 185-191.

Wang, N. and Daun, J. K. 2005. Determination of cooking times of pulses using an automated Mattson cooker apparatus. J. Sci. Food Agric., 85:1631–1635.