Temperature Dependence of the Cooking Rate of Dry Legumes

It is well known that high temperatures reduce the cooking time of dry beans and peas. However, little quantitative information on the temperature dependence of the cooking time can be found in the literature. The temperature dependence of the cooking rate was obtained by cooking samples of dry legumes for various times at 98, 116, and 127°C and measuring the maximum force on a Kramer TP‐1 shear press with a CS‐1 cell containing 100g samples. The time‐temperature combinations which gave the same texture were plotted to obtain z‐values for softening of the beans. The following z‐values for softening due to cooking were found: Black beans: 19°C; brown beans: 18°C; soybeans: 16°C; and Alaska dried peas: 16°C. The results reported can be used for more adequate design of cooking processes of beans with special regards to energy savings since beans are frequently cooked for 5 hr at 100°C.