Preparation of canola protein isolate and use in aquaculture
A canola protein isolate useful in aquaculture is formed by a procedure in which canola oil seed meal is extracted to cause solubilization of protein in the canola oil seed meal to form an aqueous protein solution having a protein content of about 5 to about 40 g/L and a pH of about 5 to about 6.8. After separation of the aqueous protein solution from the residual canola oil seed meal, the protein concentration is increased to at least about 50 g/L while maintaining the ionic strength substantially constant by using a selective membrane technique. The concentrated protein solution is dried to provide a canola protein isolate having a protein content of at least about 90 wt % (N×6.25) d.b.
1. A feed composition for aquaculture comprising a canola protein isolate having a protein content of at least about 90 wt % (N×6.25) on a dry weight basis and having a canola protein profile which is about 40 to about 50 wt % of 2S canola protein, about 50 to about 60 wt % of 7S canola protein and about 1 to about 5 wt % of 12S canola protein.
2. The feed composition of claim 1 wherein said canola protein isolate has a protein content of at least about 100 wt % (N ×6.25).