Changes in some nutritional, bioactive and morpho-physiological properties of common bean depending on cold storage and seed moisture contents

Abstract

Seed moisture content is one of the most important storage parameters affecting the quality of stored common beans. This study was conducted to investigate the changes in some nutritional, bioactive and morpho-physiological properties of common bean stored at three different seed moisture contents (6.4, 11.7 and 17.3%), 4 °C and 65% RH for 12 months. Significant differences were determined in terms of examined properties depending on different seed moisture contents before and after storage. Protein, essential mineral contents, total phenolic content, bulk density, true density and electrical conductivity decreased consistently as seed moisture content increases both before and after storage. On the contrary, dimensional properties, shape index values, thousand grain weight and total flavonoid content increased linearly with increase of seed moisture content both before and after storage. As a result, protein, essential mineral contents (potassium, magnesium, calcium, iron, zinc, manganese), antioxidant activity, total phenolic and total flavonoid content of common bean significantly decreased at the end of 12 months storage compared with before storage, while the contents of heavy metals such as Co, Sn and Pb increased after storage. In addition to, highly significant and positive correlations were determined between L* and WI, b* and C*, Dg and Da, Dg and Sa, Sa and Sv, P and K, P and Ca, ash and pH, Zn and Cu, Se and As. The results of this study clearly indicated that low seed moisture content was the most suitable to maintain the quality of common beans for long-term storage.