Antinutrients and digestibility (in vitro) of soaked, dehulled and germinated cowpeas

Phytic acid, polyphenols, protein and starch digestibility (in vitro) in two varieties, namely CS-46 and CS-88, of soaked, dehulled and germinated cowpeas were determined. Soaking for 12 hours, dehulling of soaked seeds and germination for different time periods (24, 36 and 48 h) contributed significantly in reducing the phytic acid and polyphenol content of cowpeas. Removal of seed coat (dehulling) of soaked cowpeas reduced the polyphenols by 70-71%. Soaking (12 h) brought about an improvement in protein and starch digestibility which further increased after dehulling. Progressive increase in digestibility (protein and starch) was noticed, with an increase in germination period. Dehulling of soaked seeds was most effective in reducing the polyphenolic content, and germination in enhancing protein and starch digestibility.