Microstructural and biochemical changes in raw and germinated cowpea seeds upon high-pressure treatment

Raw and germinated cowpea seeds ( Vigna sinensis) were subjected to high-pressure treatment at 300-500 MPa for 15 min. Standard analyses, i.e., determination of protein and starch content, protein solubility, starch availability as well as microscopic observation (SEM) were used in order to study biochemical and microstructural changes in treated seeds. In opposite to germination process, the high-pressure treatment of seeds did not evoke significant changes in starch content (total and available). However, both the processes used significantly affected protein content (total and soluble). Pressurization of raw and germinated seeds evoked diversified effect on the total protein content. Whereas, the germinated seeds and/or these high pressure-treated ones demonstrated significantly higher content of soluble protein compared to raw material. The most distinct changes in microstructure of germinated seeds treated with pressure (500 MPa/15 min) were observed, and they mostly were related to the alteration in protein structure. (c) 2006 Elsevier Ltd. All rights reserved.