US4011137A
Expired / Lapsed
US
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Process for producing dextrose using mixed immobilized enzymes
Assignee: Stabra AG
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Filing: 1974-08-26
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Granted: 1977-03-08
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Expires: 1994-08-26
Abstract
Abstract Process for converting starch to dextrose wherein a partially hydrolyzed starch solution containing at least 10 percent hydrolyzed starch is contacted with an enzyme system under conditions whereby substantially complete conversion of the starch to dextrose is achieved. The enzyme system comprises immobilized glucoamylase and alpha-amylase selected from the group consisting of soluble alpha-amylase, immobilized alpha-amylase and mixtures thereof.
Inventors
- 👤 Kenneth N. Thompson
- 👤 Richard A. Johnson
- 👤 Norman E. Lloyd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:05
CPC Classifications
C; C12; C12P; C12P19/00; C12P19/20; C12N; C12N11/00; C12N11/02; C12N11/10; C12N11/14; C12N11/18; C13; C13K; C13K1/00; C13K1/06; Y; Y10; Y10S; Y10S435/00; Y10S435/813; Y10S435/8215; Y10S435/822; Y10S435/832; Y10S435/839; Y10S435/911; Y10S435/913; Y10S435/918
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
104 words
A process for converting starch to dextrose comprising treating starch with alpha-amylase to obtain a partially hydrolyzed starch solution containing at least 10 percent hydrolyzed starch and then treating the partially hydrolyzed starch solution with an enzyme system comprising immobilized glucoamylase selected from the group consisting of glucoamylase covalently bonded to an insoluble carrier and glucoamylase adsorbed on an insoluble carrier and immobilized alpha-amylase selected from the group consisting of alpha-amylase covalently bonded to an insoluble carrier and alpha-amylase adsorbed on an insoluble carrier under conditions whereby a hydrolysate containing at least about 92 percent dextrose on an ash free, dry basis is produced.
Claim 2
Dependent Claim
104 words
A process for converting starch to dextrose comprising treating starch with alpha-amylase to obtain a partially hydrolyzed starch solution containing at least 10 percent hydrolyzed starch and then treating the partially hydrolyzed starch solution with an enzyme system comprising immobilized glucoamylase selected from the group consisting of glucoamylase covalently bonded to an insoluble carrier and glucoamylase adsorbed on an insoluble carrier and immobilized alpha-amylase selected from the group consisting of alpha-amylase covalently bonded to an insoluble carrier and alpha-amylase adsorbed on an insoluble carrier under conditions whereby a hydrolysate containing at least about 92 percent dextrose on an ash free, dry basis is produced.
Claim 3
Dependent Claim
45 words
A process for converting starch to dextrose as defined in claim 1, wherein the amount of immobilized glucoamylase and the amount of immobilized alpha-amylase are such as to provide a ratio of dextrinizing activity to glucoamylase activity of at least 0.2 liquefons per glucoamylase unit.
Claim 4
Dependent Claim
45 words
A process for converting starch to dextrose as defined in claim 1, wherein the amount of immobilized glucoamylase and the amount of immobilized alpha-amylase are such as to provide a ratio of dextrinizing activity to glucoamylase activity of at least 1 liquefon per glucoamylase unit.
Claim 5
Dependent Claim
45 words
A process for converting starch to dextrose as defined in claim 1, wherein the amount of immobilized glucoamylase and the amount of immobilized alpha-amylase are such as to provide a ratio of dextrinizing activity to glucoamylase activity of at least 3 liquefons per glucoamylase unit.
Claim 6
Dependent Claim
32 words
A process for converting starch to dextrose as defined in claim 1, wherein the immobilized alpha-amylase is prepared from a soluble alpha-amylase preparation having a S/L value of at least about 3.
Claim 7
Dependent Claim
32 words
A process for converting starch to dextrose as defined in claim 1, wherein the immobilized alpha-amylase is prepared from a soluble alpha-amylase preparation having a S/L value of at least about 50.
Claim 8
Dependent Claim
32 words
A process for converting starch to dextrose as defined in claim 1, wherein the immobilized alpha-amylase is prepared from a soluble alpha-amylase preparation having a S/L value of at least about 100.
Claim 9
Dependent Claim
28 words
A process for converting starch to dextrose as defined in claim 1, wherein the partially hydrolyzed starch is contacted with a mixture of immobilized glucoamylase and immobilized alpha-amylase.
Claim 10
Dependent Claim
26 words
A process for converting starch to dextrose as defined in claim 1, wherein the alpha-amylase and the glucoamylase are immobilized on or within the same carrier.
Claim 11
Dependent Claim
31 words
A process for converting starch to dextrose as defined in claim 8, wherein the partially hydrolyzed starch solution is contacted, sequentially, with immobilized glucoamylase, with immobilized alpha-amylase and with immobilized glucoamylase.
Claim 12
Dependent Claim
34 words
A process for converting starch to dextrose as defined in claim 1, wherein the partially hydrolyzed starch solution is prepared by an enzyme treatment and has a D.E. from about 10 to about 60.
Claim 13
Dependent Claim
35 words
A process for converting starch to dextrose as defined in claim 1, wherein the temperature of the partially hydrolyzed starch solution being contacted with the enzyme system is from about 30° to about 65° C.
Claim 14
Dependent Claim
34 words
A process for converting starch to dextrose as defined in claim 12, wherein the pH of the partially hydrolyzed starch solution being contacted with the enzyme system is from about 3.5 to about 6.
Claim 15
Dependent Claim
20 words
A process for converting starch to dextrose as defined in claim 1, wherein the enzyme system includes an immobilized alpha-1,6-glucosidase.
Claim 16
Dependent Claim
19 words
A process for converting starch to dextrose as defined in claim 14, wherein the immobilized alpha-1,6-glucosidase is immobilized pullulanase.
Claim 17
Dependent Claim
22 words
A process for converting starch to dextrose as defined in claim 15, wherein the pullulanase is covalently bonded to an inert carrier.
Claim 18
Dependent Claim
21 words
A process for converting starch to dextrose as defined in claim 1, wherein the glucoamylase is adsorbed on a cellulose derivative.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-07 | 1980-09-06 | 1981-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-07 | 1984-09-06 | 1985-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-07 | 1988-09-06 | 1989-03-08 | $7700.00 | Window Closed / Lapsed |