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); 1mM HCI (pH3.0); 1mM NaOH solution (pH 11.0) and 0.1 per cent (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 per cent; respectively. Total protein content increased by 11 and 13 per cent respectively; for seeds soaked for 72 hr in plain water and 1mM HCI. In contrast; a total protein loss of 12 and 16 per cent; respectively was noted in seeds soaked for 72 hr in 1mM NaOH solution and 0.1 per cent 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 kikh showed significantly lower nutrient retention values compared to the whole seeds mainly due to the higher loss of solids during soaking