Canola protein product with low phytic acid content ("c702")

Abstract

Canola protein products having a protein content of at least about 60 wt % (N×6.25) d.b., preferably at least about 90 wt %, more preferably at lease about 100 wt %, and low phytic acid content, are produced by extracting canola seeds or canola oil seed meal with an aqueous calcium salt solution, preferably calcium chloride solution, to cause solubilization of canola protein from the seeds or meal.

What we claim is: 
     
         1 . A method of preparing a canola protein product having a protein content of at least about 60 wt % (N×6.25) dry weight basis (d.b.), which comprises:
 (a) extracting canola protein from canola seeds or canola oil seed meal using an aqueous calcium salt solution to provide an aqueous canola protein solution, 
 (b) separating the aqueous canola protein solution from spent canola oil seed meal or residual seed material and oil if the extraction was performed on canola seeds, 
 (c) optionally concentrating the separated aqueous canola protein solution, 
 (d) optionally diafiltering the concentrated canola protein solution, and 
 (e) optionally drying the concentrated and diafiltered canola protein solution to provide a canola protein product having a protein content of at least about 60 wt % (N×6.25) d.b. 
 
     
     
         2 . The method of  claim 1  wherein the aqueous calcium salt solution is aqueous calcium chloride solution. 
     
     
         3 . The method of  claim 1  wherein the concentration of the aqueous calcium salt solution is less than about 1.0 M, preferably about 0.1 to about 0.15 M. 
     
     
         4 . The method of  claim 1  wherein said extraction step is effected of a temperature of about 1° to about 100° C., preferably about 15° to about 75° C., more preferably about 15° to about 35° C. 
     
     
         5 . The method of  claim 1  wherein the extraction step is effected in a pH of about 3 to about 11, preferably about 4.5 to about 7.0. 
     
     
         6 . The method of  claim 1  wherein the aqueous calcium salt solution contains an antioxidant. 
     
     
         7 . The method of  claim 6  wherein the concentration of antioxidant in the aqueous calcium salt solution is about 0.01 to about 1 wt %, preferably about 0.05 wt %. 
     
     
         8 . The method of  claim 1  wherein the aqueous protein solution resulting from the extraction step has a protein concentration of about 5 to about 50 g/L, preferably 10 to about 50 g/L. 
     
     
         9 . The method of  claim 1  wherein fat present in the aqueous canola protein solution after separation from residual canola protein source is at least partially removed. 
     
     
         10 . The method of  claim 1  wherein oil and residual canola source material are simultaneously removed from the aqueous canola protein solution. 
     
     
         11 . The method of  claim 1  wherein the aqueous canola protein solution resulting from the separation step is treated with an adsorbent to remove colour and/or odour compounds. 
     
     
         12 . The method of  claim 1  wherein the concentration step is effected to provide a concentrated canola protein solution having a protein concentration of at least about 50 g/L, preferably at least about 200 g/L. 
     
     
         13 . The method of  claim 1  wherein said concentration step is effected by ultrafiltration utilizing a membrane having a molecular weight cut-off of about 3,000 to about 1,000,000 Daltons, preferably about 5,000 to about 100,000 Daltons. 
     
     
         14 . The method of  claim 1  wherein said diafiltration step is effected using about 1 to about 40 volumes of diafiltration solution, preferably about 2 to about 25 volumes of diafiltration solution, optionally in the presence of an antioxidant for at least a portion of the step. 
     
     
         15 . The method of  claim 14  wherein the diafiltration step is effected using a membrane having a molecular weight cut-off of about 3,000 to about 1,000,000 Daltons, preferably about 5,000 to about 100,000 Daltons. 
     
     
         16 . The method of  claim 14  wherein diafiltration is effected prior to the concentration step, on partially concentrated canola protein solution or on fully concentrated canola protein solution. 
     
     
         17 . The method of  claim 12  and  claim 14  wherein the concentration step and/or the diafiltration step are effected at a temperature of about 2° to about 60° C., preferably about 20° to about 35° C. 
     
     
         18 . The method of  claim 1  wherein the optionally concentrated and optionally diafiltered canola protein solution is polished to remove residual particulates. 
     
     
         19 . The method of  claim 1  wherein the optionally concentrated and optionally diafiltered canola protein solution is treated with an adsorbent to remove colour and/or odour compounds. 
     
     
         20 . The method of  claim 1  wherein the optionally concentrated and optionally diafiltered canola protein solution is pasteurized by heating at a temperature of about 55° to about 70° C. for about 30 seconds to about 60 minutes, preferably about 60° to about 65° C. for about 10 to about 15 minutes. 
     
     
         21 . The method of  claim 1  wherein the optionally concentrated and optionally diafiltered canola protein solution is dried to provide a canola protein product having a protein content of at least about 90 wt % (N×6.25), preferably at least about 100 wt % (N×6.25). 
     
     
         22 . A canola protein product produced by the method of  claim 1 . 
     
     
         23 . The canola protein product of  claim 22  having a phytic acid content of less than about 1.5 wt %, preferably less than about 0.5 wt %.