Physicochemical properties and enzymatic bean grains dried at different temperatures and stored for 225 days

Beans are an important food in the world and are present on the tables of Brazilians almost daily. The harvest of these grains occurs seasonally during the year, and hence, steps after harvesting are essential to maintain product demand. However, the drying and storage conditions may alter the characteristics of the beans, reducing their economic value and their acceptability to consumers. The objective of this study was to evaluate the impact of storage time on the chemical, technological and enzymatic parameters of black beans dried at three temperatures (30, 45 and 60 °C) and stored for 225 days in conventional woven polypropylene bags. The results show that the increase in storage time leads to a lower protein solubility, and a decreased content of tannins, lipids and proteins; and an increased cooking time, fat acidity, and the enzymatic activity of peroxidase and polyphenol oxidase. These parameters are important in the quality control of beans for consumption and as a raw material for the food industry. The quantity of broken grains and the grain roughness index are only influenced by the drying temperature regardless of the storage time of 225 days.