Process for enhancing solubility of plant protein compositions
The present disclosure discloses methods for preparing plant-based protein compositions, such as a pea protein isolate, comprising alkaline phosphate salts, wherein the compositions exhibit greatly improved solubility. The high solubility of these plant-based protein isolate compositions greatly facilitates the manufacture of food and beverage products containing plant-based protein.
1. A method for producing a pea protein composition comprising:
(a) adding an alkaline phosphate salt composition to an aqueous solution of a pea protein isolate having a protein content of 5-20%, wherein the added alkaline phosphate salt composition to protein content on a dry weight basis is 3-98%, 3-45%, 4-20%, or 10-95%, wherein the added alkaline phosphate salt composition comprises a salt of an orthophosphate ion;
(b) pasteurizing the solution of step (a) to a temperature of 73-86° C. for at least 30-70 seconds; and
(c) drying the solution of step (b) to form a pea protein composition having a protein content of at least 70%.
2. The method of claim 1 , wherein the added alkaline phosphate salt composition comprises trisodium phosphate and/or tripotassium phosphate; optionally, in an amount of 5-100 wt %.
3. The method of claim 2 , wherein the added alkaline phosphate salt composition to protein content on a dry weight basis is 3-45%, or 4-20%.
4. The method of claim 2 , wherein the added alkaline phosphate salt composition further comprises hexametaphosphate sodium salt and/or hexametaphosphate potassium salt; optionally, in an amount of 5-95 wt. %.
5. The method of claim 4 , wherein the added alkaline phosphate salt composition to protein content on a dry weight basis is 10-95%.
6. The method of claim 1 , wherein the aqueous solution of plant protein isolate is pH 5-10.
7. The method of claim 1 , wherein the pea protein isolate is:
(a) a base-extracted pea protein isolate; or
(b) a neutral-extracted pea protein isolate.
8. The method of claim 1 , wherein step (c) comprises spray-drying the solution to form a powder pea protein composition.
9. The method of claim 1 , wherein the pea protein composition exhibits an aqueous solubility at pH 7 of at least 20%, at least 25%, at least 30%, at least 40%, at least 50%, or at least 60%.
10. The method of claim 1 , wherein the aqueous solubility at pH 7 of the pea protein composition relative to the aqueous solubility at pH 7 of a pea protein composition prepared without adding an alkaline phosphate salt composition comprising a salt of an orthophosphate ion to an aqueous solution of pea protein isolate having a protein content of 5-20% is increased by at least 2-fold, at least 3-fold, at least 4-fold, at least 5-fold, or more.
11. A pea protein composition prepared according to the method of claim 1 .
12. A food or beverage product comprising a pea protein composition prepared according to the method of claim 1 .
13. A pea protein composition comprising a dried pea protein isolate comprising at least 70 wt. % protein content and an added alkaline phosphate salt composition to protein content on a dry weight basis of 3-98%, 3-45%, 4-20%, or 10-95%, wherein the alkaline phosphate salt composition comprises a salt of an orthophosphate ion.
14. The composition of claim 13 , wherein the alkaline phosphate salt composition comprises trisodium phosphate and/or tripotassium phosphate; optionally, in an amount of 5-100 wt. %, 70-100 wt. %, 80-100 wt. %, or 90-100 wt. %.
15. The composition of claim 14 , wherein the added alkaline phosphate salt composition to protein content on a dry weight basis is 3-45%, or 4-20%.
16. The composition of claim 13 , wherein the alkaline phosphate salt further comprises hexametaphosphate sodium salt and/or hexametaphosphate potassium salt; optionally, in an amount of 5-95 wt. %, 50-80%, 70-95 wt. %, 80-95 wt. %, or 90-95 wt. %.
17. The composition of claim 16 , wherein the added alkaline phosphate salt composition to protein content on a dry weight basis is 10-95%.
18. The composition of claim 13 , wherein the composition has an aqueous solubility at pH 7 of at least 20%, at least 25%, at least 30%, at least 40%, at least 50%, or at least 60%.
19. The composition of claim 13 , wherein the aqueous solubility at pH 7 of the composition relative to the aqueous solubility at pH 7 of a pea protein composition without the alkaline phosphate salt is increased by at least 2-fold, at least 3-fold, at least 4-fold, at least 5-fold, or more.
20. The composition of claim 13 , wherein the plant protein isolate is a base-extracted plant protein isolate; optionally, a base-extracted plant protein isolate prepared by extraction of a plant protein concentrate solution with 10-100 mM NaOH.
21. The composition of claim 13 , wherein the plant protein isolate is a neutral-extracted plant protein isolate; optionally, a neutral-extracted plant protein isolate is prepared by extraction of a plant protein concentrate solution with hot water.
22. A food or beverage product comprising a pea protein composition according to claim 13 .