An improved technique for plant protein extraction

Studies on the extractability of plant protein showed that solubilisation of protein from plants harvested at different stages of growth before flowering depended on the water content of the macerated plant material and the level of alkalinity. Solubilisation increased as the pH value was raised from 6.2 to 11.00 by addition of NaOH solution and as the dry matter content decreased from 90 to 37.5 g/kg of mixture by water dilution. A dry matter concentration of 45 g/kg and pH 11 were adopted as most suitable extraction conditions which allowed 82‐86% nitrogen yield from the five plant species tested. Ageing of plants had an adverse effect on nitrogen extractability. Of the total extractable nitrogen, the true protein nitrogen content increased with age up to commencement of flowering but once flowering had commenced the content was lower