US4863613A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Soy protein isolation process using swellable poly(N-isopropylacrylamide) gels
Assignee: University of Minnesota System
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Filing: 1988-10-13
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Granted: 1989-09-05
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Expires: 2008-10-13
Abstract
Abstract A method is provided for the purification and concentration of soy protein comprising mixing an aqueous solution including soy protein along with other water soluble moieties including sugars, salts, and phytins with a solid crosslinked polymer gel selected from the group consisting of N-substituted polyacrylamides and copolymers of N-substituted polyacrylamides; swelling the gel to absorb a portion of the water and other water soluble moieties including sugars, salts, and phytins from the aqueous solution by substantially maintaining the temperature of the gel at a preselected temperature below the lower critical solution temperature of the gel, to yield a concentrated soy protein solution; and separating the concentrated soy protein solution from the swollen gel. The concentrated soy protein solution may be repeatedly subjected to the gel treatment depending on the desired purity of the protein and the desired solids concentration.
Inventors
- 👤 Dale W. Johnson
- 👤 Edward L. Cussler
- 👤 Steven J. Trank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:58
CPC Classifications
A; A23; A23J; A23J3/00; A23J3/14; A23J3/16; A23J1/00; A23J1/14; B; B01; B01D; B01D15/00; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/903; Y10S210/905
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
139 words
A method for the purification and concentration of soy protein comprising: (a) mixing an aqueous solution comprising soy protein and phytin with a solid crosslinked polymer gel selected from the group consisting of N-substituted polyacrylamides and copolymers of N-substituted polyacrylamides; (b) swelling said gel to absorb a portion of the water and of said phytin from said aqueous solution by substantially maintaining the temperature of said gel at a preselected temperature below the lower critical solution temperature of said gel, to yield a concentrated soy protein solution as a retentate; (c) separating said concentrated soy protein solution from said swollen gel; and (d) washing said swollen gel with water having a temperature at or below said preselected temperature, to yield a wash solution which is combined with said concentrated soy protein solution to yield a concentrated soy protein dispersion.
Claim 2
Independent Claim
139 words
A method for the purification and concentration of soy protein comprising: (a) mixing an aqueous solution comprising soy protein and phytin with a solid crosslinked polymer gel selected from the group consisting of N-substituted polyacrylamides and copolymers of N-substituted polyacrylamides; (b) swelling said gel to absorb a portion of the water and of said phytin from said aqueous solution by substantially maintaining the temperature of said gel at a preselected temperature below the lower critical solution temperature of said gel, to yield a concentrated soy protein solution as a retentate; (c) separating said concentrated soy protein solution from said swollen gel; and (d) washing said swollen gel with water having a temperature at or below said preselected temperature, to yield a wash solution which is combined with said concentrated soy protein solution to yield a concentrated soy protein dispersion.
Claim 3
Dependent Claim
21 words
The method of claim 1 further comprising: (e) drying the concentrated soy protein dispersion to yield a concentrated soy protein isolate.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein said crosslinked polymer gel is in particulate form.
Claim 5
Dependent Claim
19 words
The method of claim 1 wherein said crosslinked polymer gel swells to at least 5 times its initial volume.
Claim 6
Dependent Claim
20 words
The method of claim 1 wherein said crosslinked polymer gel is swollen and collapsed over an about 5° C. range.
Claim 7
Dependent Claim
14 words
The method of claim 1 wherein said crosslnked polymer gel is a poly(N-isopropylacrylamide) gel.
Claim 8
Dependent Claim
22 words
The method of claim 6 wherein said crosslinked polymer igel is apoly(N-isopropylacrylamide) crosslinked with N,N-methylenebisacrylamide and is swollen at about 25°-32° C.
Claim 9
Dependent Claim
23 words
The method of claim 1 wherein the soy protein concentration in said aqueous solution comprising soy prctein and phytin is about 10-20 wt-%.
Claim 10
Dependent Claim
17 words
The method of claim 1 wherein said gel of step (b) is swollen at about 4°-10° C.
Claim 11
Dependent Claim
28 words
The method of claim 1 wherein said crosslinked polymer gel is a copolymer of poly(N,N-diethylacrylamide) and sodium methacrylate crosslinked with N,N-methylenebisacrylamide, and is swollen at about 25°-55° C.
Claim 12
Dependent Claim
69 words
The method of claim 1, further comprising: (e) warming said swollen gel of step (c) to a temperature above said lower critical solution temperature of said gel, so that said gel undergoes a phase change and shrinks to a reduced volume, to release a major portion of said absorbed water and said absorbed phytin; and (f) separating said released water and said released phytin from said reduced volume gel.
Claim 13
Dependent Claim
23 words
The method of claim 11 wherein the volume of said reduced volume gel is about 5-20% of the volume of said swollen gel.
Claim 14
Dependent Claim
14 words
The method of claim 11 wherein said crosslinked polymer gel is a poly(N-isopropylacrylamide) gel.
Claim 15
Dependent Claim
81 words
The method of claim 1, further comprising: (e) mixing said combined solution of said wash solution and said concentrated soy protein solution with said reduced volume gel and maintaining the mixture at a preselected temperature below said lower critical solution temperature of said gel, to swell said gel and to absorb a further portion of said water by said gel to yield a further concentrated soy protein solution; and (f) separating said further concentrated soy protein solution from said swollen gel.
Claim 16
Dependent Claim
24 words
The method of claim 14, further comprising: (g) drying said separated further concentrated soy protein solution to yield a further concentrated soy protein isolate.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1992-09-04 | 1993-03-06 | 1993-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-04 | 1997-03-06 | 1997-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-04 | 2001-03-06 | 2001-09-05 | $7700.00 | Window Closed / Lapsed |