Deshpande and Damodaran (1990) also affirms that during cooking of whole beans heat convection may further facilitates cell separation and the development of the uniform, smooth texture in fully cooked beans (Reyes-Moreno & Paredes-Lopéz, 1993). AG characteristics were the same of the FG for Test 2 and Test 3 (slightly undercooked grains), but not for Test 4, which has been

classified as slightly overcooked, due to the longer cooking time applied in its process. As grain hardness is a response to the time adopted in the cooking step and the system conditions, it is necessary to set the same cooking time for all samples and to standardize Roxadustat supplier the cooking system to allow analyses to be repeated and compared. When the CT was standardized at 30, 45 and 60 min on the

hotplate with the covered beaker (Table 3), the hardness of beans reduced as the cooking time increased and those with longer storage time (AG) presented harder grains than FG. CT of 30 min generated grains slightly undercooked, with similar hardness between freshly and buy CX-5461 aged beans (3.5 ± 0.6 and 3.7 ± 0.2 N, respectively), demonstrating not to be a good method to differentiate recently harvested grains from those with long storage period. CT of 45 min could well distinguish fresh from aged grains, with the FG presenting cooked and the AG slightly undercooked characteristics. However, hardness of AG was not significantly different for those cooked at 30 and 45 min. Extending the CT to 60 min, AG became cooked and FG slightly overcooked. Earlier research (Revilla & Vivar-Quintana, 2008) also indicated that the longer time used in the cooking step (60 min) improved the grain softness. Furthermore, Bressani and Gómez-Brenes (1985) developed a simple equipment that measures objectively the hardness of individual grains, and demonstrated that the first 30 min

of cooking in boiling water differentiates hardness of Thymidine kinase freshly and aged black bean grains. Besides the harvest time, 60 min of cooking also differentiates the temperature at which the grains were stored. The hardness of FG and AG was tested after cooking at an autoclave using different conditions of process (Table 3), to simulate the traditional cooking procedure used by consumer to prepare bean grains. It was observed that the binomial time × temperature and also the pressure of the cooking system affected the final hardness of bean grains. Test 8 presented the milder condition of cooking (105 °C/10 min, 117.7 kPa) and generated grains slightly undercooked, independent of the storage time. On the other hand, Test 10, which presented the more severe condition of cooking (115 °C/20 min, 166.7 kPa), generated grains overcooked, with very soft cotyledon and tegument and low grain integrity. Therefore, the moderate condition of 110 °C/15 min, 137.