THE EFFECT OF SOAKING TIME AND SOAKING SOLUTION ON THE NUTRITIONAL QUALITY OF GRASS PEA SEEDS

Abstract

The effect of soaking time and soaking solution on the nutritional quality of grass pea seeds were studied. The soaking solutions used were:plain water (pH 7.3); ImM HCl (pH 3.0); ImM NaOH solution (pH 11.0) and 0.1% (w/v) wood ash solution (pH 12.0). Mature whole grass pea seeds soaked for 72 hr in the four soak media that were used resulted in total solids loss of 1.3, 1.2, 5.2 and 6.2 percent, respectively. Total protein content increased by 11 and 13 percent, respectively for seeds soaked for 72 hr in plain water and ImM HCl. In contrast, a total protein loss of 12 and 16 percent, respectively was noted in seeds soaked for 72 hr in ImM NaOH solution and 0.1% wood ash solution. The soaking process resulted in the loss of non protein nitrogen, total soluble sugars and reducing sugars. Soaking also influenced the ash and crude fibre contents of the seeds. The pH of the soaking solutions were also altered in accordance to the soaking process. However 'kikn' showed significantly lower nutrient retention values compared to the whole seeds mainly due to the higher loss of solids during soaking