Canola Protein Isolate Compositions

Abstract

A new canola protein isolate is provided along with a new canola protein. The new canola protein isolate is obtained from the supernatant from the production of a canola protein micellar mass and contains a predominance of 2S protein. The canola protein isolate derived from PMM contains a predominance of a 7S protein. Compositions of the canola protein isolate are provided.

1 . A canola protein isolate having a protein content of at least about 90 wt % on a dry weight basis and at a Kjeldahl nitrogen conversion of N×6.25 and which exhibits a protein profile which is:
 about 60 to about 95% wt % of 2S protein,   about 5 to about 40 wt % of 7S protein, and   0 to about 5 wt % of 12S protein.   
   
   
       2 . The isolate of  claim 1  which exhibits a protein profile which is:
 about 70 to about 95 wt % of 2S protein,   about 5 to about 30 wt % of 7S protein, and   0 to about 2 wt % of 12S protein.   
   
   
       3 . The isolate of  claim 2  having a protein content of at least about 100 wt %. 
   
   
       4 . A canola protein isolate composition comprising:
 (1) a first canola protein isolate having a protein content of at least about 90 wt % on a dry weight basis and at a Kjeldahl nitrogen conversion of N×625 and which exhibits a protein profile which is:
 about 60 to about 98 wt % of 7S protein, 
 about 1 to about 15 wt % of 12S protein, 
 0 to about 25 wt % of 2S protein, and 
   (2) a second canola protein isolate having a protein content of at least about 90 wt % on a dry weight basis and a Kjeldahl nitrogen conversion of N×6.25 and which exhibits a protein profile which is;
 about 60 to about 95 wt % of 2S protein 
 about 5 to about 40 wt % of 7S protein 
 0 to about 5 wt % of 12S protein. 
   
   
   
       5 . The composition of  claim 4  wherein said first canola protein isolate and said second canola protein isolate are present in said composition in a weight ratio of about 5:95 to about 95:5. 
   
   
       6 . The composition of  claim 5  wherein said first canola protein isolate exhibits a protein profile which is:
 about 88 to about 98 wt % of 7S protein,   about 1 to about 10 wt % of 12S protein, and   0 to about 6 wt % of 2S protein.   
   
   
       7 . The composition of  claim 6  wherein said first canola protein isolate has a protein content of at least about 100 wt %. 
   
   
       8 . The composition of  claim 5  wherein the second canola protein isolate exhibits a protein profile which is:
 about 70 to about 95 wt % of 2S protein,   about 5 to about 30 wt % of 7S protein, and   0 to about 2 wt % of 12S protein.   
   
   
       9 . The composition of  claim 8  wherein the second canola protein isolate has a protein content of at least about 100 wt %. 
   
   
       10 . An isolated and purified 7S protein of canola. 
   
   
       11 . The protein of  claim 10  having a molecular weight, as determined by MALDI-MS, of about 145 kDa. 
   
   
       12 . The protein of  claim 11  which is comprised of three subunits, each sized approximately 413 amino acids. 
   
   
       13 . The protein of  claim 12  having an amino acid analysis substantially as set forth in Table VII or Table VIII. 
   
   
       14 . The protein of  claim 10  which is isolated and purified from a canola protein micellar mass. 
   
   
       15 . The protein of  claim 14  wherein said protein micellar mass is formed by diluting a concentrated saline solution of canola protein extracted from canola oil seed meal under mildly acidic conditions. 
   
   
       16 . A composition, comprising a mixture of an isolated and purified 7S protein of canola protein and at least one additional isolated and purified canola protein extracted from the group consisting of the 2S and 12S canola proteins. 
   
   
       17 . A method of isolating and purifying an individual canola protein from a canola protein isolate containing a mixture of at least two different canola proteins selected from the group consisting of the 2S, 7S and 12S proteins, which comprises:
 providing said canola protein isolate having a protein contents of at least about 90 wt % on a dry weight basis and at a Kjeldahl nitrogen conversion of N×6.25,   solubilizing the canola protein isolate,   subjecting the resulting protein solution to preparative high pressure liquid chromatography or equivalent procedure separating proteins on the basis of molecular size,   collecting fractions of eluant containing the individual selected canola protein,   subjecting the selected fractions to ultrafiltration to reduce the volume of eluant,   dialyzing the concentrated eluant to remove solubilizing material, and drying the dialyzate to recover the individual canola protein.   
   
   
       18 . The method of  claim 17  wherein said canola protein isolate is one which exhibits a protein profile which is:
 about 60 to about 98 wt % of 7S protein,   about 1 to about 15 wt % of 12S protein, and   0 to about 25 wt % of 2S protein.   
   
   
       19 . The method of  claim 18  wherein said canola protein exhibits a protein profile which is:
 about 88 to about 98 wt % of 7S protein,   about 1 to about 10 wt % of 12S protein, and   0 to about 6 wt % of 2S protein.   
   
   
       20 . The method of  claim 18  wherein said canola protein isolate is processed to isolate and purify the 7S and/or 12S proteins. 
   
   
       21 . The method of  claim 17  wherein said canola protein isolate is one which exhibits a protein profile which is:
 about 60 to about 95 wt % of 2S protein, about 5 to about 30 wt % of 7S protein, 0 to about 2 wt % of 12S protein.   
   
   
       22 . The method of  claim 21  wherein said canola protein isolate exhibits a protein profile which is:
 about 70 to about 95 wt % of 2S protein,   about 5 to about 30 wt % of 7S protein,   0 to about 2 wt % of 12S protein.   
   
   
       23 . The method of  claim 21  wherein said canola protein isolate is processed to isolate and purify the 2S protein.