Preparation of non-soy oilseed protein products ("*810")

Abstract

The present invention is directed to non-soy oilseed protein products, very low in, or free of, beany, green, vegetable or similar flavour notes and useful for the fortification of food and beverage products and prepared without the use of salt in the process. The non-soy oilseed protein products of the present invention are obtained by extracting non-soy oilseed protein source with water to form an aqueous non-soy oilseed protein solution, at least partially separating the aqueous non-soy oilseed protein solution from residual non-soy oilseed protein source, adjusting the pH of the aqueous non-soy oilseed protein solution to a pH between about 1.5 and a value about 1 pH unit lower than the typical pH of isoelectric precipitation to solubilize the bulk of the protein and form an acidified non-soy oilseed protein solution then separating the acidified non-soy oilseed protein solution from the acid insoluble solid material. The acidified non-soy oilseed protein solution may be dried following optional concentration and diafiltration to form a non-soy oilseed protein product, which may be an isolate. The acid insoluble solid material may be washed with acidified water and then dried to form another non-soy oilseed protein product. These products may be dried at the acidic pH at which they were prepared or may be adjusted in pH before drying.

What we claim is: 
     
         1 . A process of producing a sunflower protein product having a protein content selected from the group consisting of at least about 60, at least about 65, at least about 70, at least about 75, at least about 80, at least about 85 or at least about 90 wt % (N×6.25) on a dry weight basis, which process comprises:
 (a) extracting a sunflower protein source with water to cause solubilization of protein from the sunflower protein source and to form an aqueous protein solution and a residual sunflower protein source, 
 (b) at least partially separating the aqueous sunflower protein solution from the residual sunflower protein source, 
 (c) adjusting the pH of the aqueous sunflower protein solution to a pH of about 1.5 to about 3.5 to produce an acidified sunflower protein solution, 
 (d) separating the acid insoluble solid material from the acidified sunflower protein solution, 
 (e) optionally concentrating the acidified sunflower protein solution by a selective membrane technique, 
 (f) optionally diafiltering the optionally concentrated sunflower protein solution, and 
 (g) optionally drying the optionally concentrated and optionally diafiltered sunflower protein solution. 
 
     
     
         2 . The process of  claim 1 , wherein said acid insoluble solid material is optionally diluted then optionally dried to form a sunflower protein product having a protein content of at least about 60, at least about 65, at least about 70, at least about 75 or at least about 80 wt % (N×6.25) on a dry weight basis. 
     
     
         3 . The process of  claim 2 , wherein the pH of the optionally diluted acid insoluble solid material is raised to a value selected from the group consisting of less than about 8.0, about 6.0 to about 8.0 and about 6.5 to about 7.5, prior to the optional drying step. 
     
     
         4 . The process of  claim 2 , wherein said acid insoluble solid material is washed by mixing with a quantity of water selected from the group consisting of about 1 to about 20 volumes of water and about 1 to about 10 volumes of water, having a pH selected from the group consisting of about 1.5 to about 3.5 and about the same as the pH of the acid insoluble material, then is separated from the wash solution prior to optional dilution then optional drying steps to obtain a sunflower protein product having a protein content of at least about 60, at least about 65, at least about 70, at least about 75, at least about 80, at least about 85 or at least about 90 wt % (N×6.25) on a dry weight basis. 
     
     
         5 . The process of  claim 4 , wherein the pH of the optionally diluted washed acid insoluble material is raised to a value selected from the group consisting of less than about 8.0, about 6.0 to about 8.0 and about 6.5 to about 7.5, prior to the optional drying step. 
     
     
         6 . The process of  claim 4  wherein the wash solution is combined with the acidified sunflower protein solution of step (d) and processed as in at least one of steps (e)-(g). 
     
     
         7 . The process of  claim 2 , wherein said acid insoluble solid material is simultaneously washed and adjusted in pH by mixing the acid insoluble solid material with a quantity of water selected from the group consisting of about 1 to about 20 volumes of water and about 1 to about 10 volumes of water, and sufficient food grade alkali to raise the pH to a value selected from the group consisting of less than about 8.0 and between about 5.0 and about 8.0, then is separated from the wash solution by centrifugation, prior to optional dilution then optional drying steps. 
     
     
         8 . The process of  claim 7 , wherein the optionally diluted simultaneously washed and pH adjusted acid insoluble solid material is further raised in pH as to a value selected from the group of less than about 8.0, between about 6.0 and about 8.0 and between about 6.5 and about 7.5, prior to the optional drying step. 
     
     
         9 . The process of  claim 1 , wherein following step b) said separated residual sunflower protein source is re-extracted to recover residual protein. 
     
     
         10 . The process of  claim 2 , wherein said optionally diluted acid insoluble solid material is pasteurized prior to drying, optionally at a temperature and for a time selected from the group consisting of about 55° to about 85° C. for about 10 seconds to about 60 minutes, about 60° to about 70° C. for about 10 minutes to about 60 minutes and about 70° C. to about 85° C. for about 10 seconds to about 60 seconds. 
     
     
         11 . The process of  claim 3  wherein said optionally diluted and pH adjusted acid insoluble solid material is pasteurized prior to drying, optionally at a temperature and for a time selected from the group consisting of about 55° to about 85° C. for about 10 seconds to about 60 minutes, about 60° to about 70° C. for about 10 minutes to about 60 minutes and about 70° C. to about 85° C. for about 10 seconds to about 60 seconds. 
     
     
         12 . The process of  claim 4  wherein said optionally diluted washed acid insoluble solid material is pasteurized prior to drying, optionally at a temperature and for a time selected from the group consisting of about 55° to about 85° C. for about 10 seconds to about 60 minutes, about 60° to about 70° C. for about 10 minutes to about 60 minutes and about 70° C. to about 85° C. for about 10 seconds to about 60 seconds. 
     
     
         13 . The process of  claim 5  wherein said optionally diluted washed and pH adjusted acid insoluble solid material is pasteurized prior to drying, optionally at a temperature and for a time selected from the group consisting of about 55° to about 85° C. for about 10 seconds to about 60 minutes, about 60° to about 70° C. for about 10 minutes to about 60 minutes and about 70° C. to about 85° C. for about 10 seconds to about 60 seconds. 
     
     
         14 . The process of  claim 7  wherein said optionally diluted simultaneously washed and pH adjusted acid insoluble solid material is pasteurized prior to drying, optionally at a temperature and for a time selected from the group consisting of about 55° to about 85° C. for about 10 seconds to about 60 minutes, about 60° to about 70° C. for about 10 minutes to about 60 minutes and about 70° C. to about 85° C. for about 10 seconds to about 60 seconds. 
     
     
         15 . The process of  claim 8  wherein said optionally diluted simultaneously washed and pH adjusted and further pH adjusted acid insoluble solid material is pasteurized prior to drying, optionally at a temperature and for a time selected from the group consisting of about 55° to about 85° C. for about 10 seconds to about 60 minutes, about 60° to about 70° C. for about 10 minutes to about 60 minutes and about 70° C. to about 85° C. for about 10 seconds to about 60 seconds. 
     
     
         16 . The process of  claim 1 , wherein the extraction step a) comprises a counter-current extract procedure. 
     
     
         17 . The process of  claim 1  wherein said extraction step (a) is effected at a temperature selected from the group consisting of about 1° to about 100° C., about 15° to about 65° C., and about 50° to about 60° C. 
     
     
         18 . The process of  claim 1  wherein said water used for the extraction contains a pH adjusting agent so that the extraction is conducted at a pH selected from the group consisting of about 6 to 11 and about 7 to about 8.5. 
     
     
         19 . The process of  claim 18  wherein the pH adjusting agent is selected from sodium hydroxide, potassium hydroxide and combinations thereof. 
     
     
         20 . The process of  claim 1  wherein said aqueous sunflower protein solution has a protein concentration selected from the group consisting of about 5 to about 50 g/L and about 10 to about 50 g/L. 
     
     
         21 . The process of  claim 1  wherein said water for extraction contains an antioxidant. 
     
     
         22 . The process of  claim 1  wherein said aqueous sunflower protein solution, after the separation step (b) and prior to the acidification step (c) is adjusted in temperature to a value selected from the group consisting of about 1 to about 35° C. and about 15 to about 35° C. 
     
     
         23 . The process of  claim 1  wherein the pH of said aqueous sunflower protein solution is adjusted in step (c) to value selected from the group consisting of about 2.0 to about 2.5. 
     
     
         24 . The process of  claim 1  wherein said acidified aqueous sunflower protein solution is dried to provide a sunflower protein product having a protein content of at least about 60 or at least about 65 wt % (N×6.25) d.b. 
     
     
         25 . The process of  claim 1  wherein said acidified aqueous sunflower protein solution is subjected to concentrating step (e) to produce a concentrated acidified sunflower protein solution having a protein concentration selected from the group consisting of about 50 to about 300 g/L, about 100 to about 200 g/L and about 50 to about 200 g/L. 
     
     
         26 . The process of  claim 25  wherein said concentration step (e) is effected by ultrafiltration using a membrane having a molecular weight cut-off selected from the group consisting of about 1,000 to about 1,000,000 daltons and about 1,000 to about 100,000 daltons. 
     
     
         27 . The process of  claim 1  wherein the acidified sunflower protein solution, partially concentrated acidified sunflower protein solution or concentrated acidified sunflower protein solution is subjected to diafiltering step (f). 
     
     
         28 . The process of  claim 27  wherein said diafiltration step (f) is effected using a diafiltration solution of water or acidified water, optionally using volumes of diafiltration solution selected from the group consisting of about 1 to about 40 volumes, and about 2 to about 25 volumes. 
     
     
         29 . The process of  claim 27  wherein said diafiltration step (f) is effected until no significant further quantities of contaminants or visible colour are present in the permeate. 
     
     
         30 . The process of  claim 27  wherein said diafiltration step (f) is effected until the retentate has been sufficiently purified so as to provide a sunflower protein isolate with a protein content of at least about 90 wt % (N×6.25) d.b. 
     
     
         31 . The process of  claim 27  wherein said diafiltration step (f) is effected using a membrane having a molecular weight cut-off selected from the group consisting of about 1,000 to about 1,000,000 daltons and about 1,000 to about 100,000 daltons. 
     
     
         32 . The process of  claim 27  wherein an antioxidant is present in the diafiltration medium during at least part of the diafiltration step (f). 
     
     
         33 . The process of  claim 25  wherein said concentration step (e) is carried out at a temperature selected from the group consisting of about 2° to about 65° C. and about 50° to about 60° C. 
     
     
         34 . The process of  claim 27  wherein said diafiltration step (f) is carried out at a temperature selected from the group consisting of about 2° to about 65° C. and about 50° to about 60° C. 
     
     
         35 . The process of  claim 1  wherein step e) and/or step f) are carried out and said concentrated and/or diafiltered acidified protein solution is pasteurized prior to drying. 
     
     
         36 . The process of  claim 35  wherein said pasteurization step is effected at a temperature and for a time selected from the group consisting of about 55° to about 85° C. for about 10 seconds to about 60 minutes, about 60° to about 70° C. for about 10 minutes to about 60 minutes and about 70° C. to about 85° C. for about 10 seconds to about 60 seconds. 
     
     
         37 . The process of  claim 27  wherein said concentrated and diafiltered acidified sunflower protein solution is subjected to drying step (g) to provide a sunflower protein isolate having a protein content of at least about 90 wt % (N×6.25) d.b. 
     
     
         38 . The process of  claim 1  wherein the pH of the optionally concentrated and optionally diafiltered acidified sunflower protein solution is raised to a value selected from the group consisting of less than about 8.0, about 6.0 to about 8.0 and about 6.5 to about 7.5, to produce a pH adjusted sunflower protein solution, prior to drying step (g). 
     
     
         39 . The process of  claim 1 , wherein the sunflower protein source is in partially or fully defatted form. 
     
     
         40 . A sunflower protein product having a protein content of at least about 60, at least about 65, at least about 70, at least about 75, at least about 80, at least about 85 or at least about 90 wt % (N×6.25) d.b. and which:
 is prepared without a process step involving the direct addition of salt; and 
 wherein the sunflower protein product has a substantially clean flavour, which comprises little or no beany, green or vegetable flavour or off flavour. 
 
     
     
         41 . The sunflower protein product of claim  58  which is derived from a partially or fully defatted sunflower protein source. 
     
     
         42 . A food product formulated to contain the sunflower protein product of  claim 40 . 
     
     
         43 . The food product of  claim 42 , which is a beverage.