Filtration method for producing value added products from rice bran

Abstract

A process for treating rice bran utilizing a shear pump to circulate a solution comprising an enzyme, an acid and water with rice bran in a mixing tank, then after a first predetermined period transferring a portion of the solution to a feed tank, and then over a second predetermined period filtering the solution in the feed tank through multiple filtration units each having a pre-selected pore size to obtain pre-determined value-added by-products from the rice bran.

Claims

1. A process for extracting a value-added product from rice bran comprising: a. Circulating a solution comprising an enzyme, an acid, water, and rice bran in a tank; b. after a first predetermined period, filtering the solution over a second predetermined period to produce a permeate stream and a retentate stream; and c. drying the permeate stream to remove substantially all of the water in the permeate stream to produce a high-fat fiber value-added product.

2. The process according to claim 1 wherein the filtering step is performed using an MWCO filter.

3. The process according to claim 2 wherein the MWCO filter is selected from the group consisting of 500,000; 100,000; 30,000; 1000; and 100 MWCO filters.

4. The process according to claim 1 further comprising filtering the solution a plurality of times to create a plurality of permeate streams.

5. The process according to claim 4 wherein the plurality of filtering steps are performed using a plurality of MWCO filters.

6. The process according to claim 5 wherein the plurality of MWCO filters are selected from the group consisting of 500,000; 100,000; 30,000; 1000; and 100 MWCO filters.

7. The process according to claim 5 wherein each of the plurality of MWCO filters used in the plurality of filtering steps have a different molecular weight cut-off.

8. The process of claim 1 wherein the solution is comprised of about 0.1% by weight enzyme; about 0.2% by weight acid; about 15.3% by weight rice bran; and about 84.4% by weight of water.

9. The process of claim 8 wherein the enzyme is selected from the group consisting of amylase, amyloglucosidase, pentosanase, hexosanase, or and combinations thereof.

10. The process of claim 8 wherein the acid is selected from the group consisting of organic acids and mineral acids and wherein the solution has a pH range of 4.0 to 9.0.

11. The process of claim 1, wherein the first predetermined period is about 1.5-4.0 hours.

12. The process of claim 1, wherein the second predetermined period is about 0.5-1.5 hours.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1 is a flow diagram illustrating the process steps of the invention utilizing a 500,000 MWCO ultrafilter to produce a high-fat fiber product useful in human or animal feed.

(2) FIG. 2 is a preferred flow diagram utilizing a 100,000 MWCO ultrafilter to produce milk or egg replacer product from the permeate from the 500,000 MWCO ultrafilter in FIG. 1.

(3) FIG. 3 is a preferred flow diagram utilizing a 30,000 MWCO ultrafilter to produce a rice bran protein isolate product from the permeate from the 100,000 MWCO ultrafilter in FIG. 2.

(4) FIG. 4 is a preferred flow diagram utilizing a 1,000 MWCO nanofilter to produce a nutraceutical product from the permeate from the 30,000 MWCO ultrafilter in FIG. 3.

(5) FIG. 5 is a preferred flow diagram utilizing a 100 MWCO reverse osmosis filter to produce non-heavy metal, low molecular weight products such as amino acids, fatty acids and sugars, and a permeate of reverse osmosis pure water from the permeate from the 1,000 MWCO nanofilter in FIG. 4.

(6) FIG. 6 is a process time schedule of the products through the various steps of a preferred process embodiment, as illustrated in FIGS. 1-5.

PREFERRED EMBODIMENTS OF THE INVENTION

(7) A typical rice bran comprising about 13% proteins by weight, about 18% fat by weight, about 25% by weight carbohydrates and about 14% by weight minerals can be used to form a slurry 1A by adding enzymes, acid and water having the following weight content ratios: about 7 pounds of enzyme:about 13 pounds of acid:about 1000 pounds of rice bran:about 5,500 pounds of water.

(8) As illustrated in FIG. 1, slurry 1A is then introduced through line 2 into a first mixing tank 3 and is mixed utilizing shear pump 4 that draws slurry 1 through intake line 5 and then through shear pump 4, and then into outflow line 6 to circulate slurry 1 back to tank 2. This circulation of slurry 1A is continued for a predetermined time to achieve a uniform acid level of about a pH level of 5.5 in the mixture, as well as better ensure the enzymes have been uniformly mixed in slurry 1A. This formation and circulation of slurry 1A preferably takes about four hours. If desired second similar slurry 1B can be introduced through line 7 into a second mixing tank 8. Then as with first slurry 1, a shear pump 9 draws slurry 1B through intake line 10 into shear pump 9 and into outflow line 11 to circulate slurry 1B back to tank 2. This formation and circulation of slurry 1B preferably also takes about four hours. If desired the circulation of slurry 1A and slurry 1B can be done simultaneously. After slurry 1A and slurry, 1B have completed their circulation cycle, the flow control valves (not shown) of shear pumps 4 and 9 can be activated to direct slurry flow from mix tanks 3 and 8 through lines 12 and 13, respectively, and into feed tank 14.

(9) The slurries 1A and 1B are then feed through the first ultrafiltration unit 15. It is preferred that unit 15 be a 500,000 MWCO unit. To ensure that slurries 1A and 1B do not blind unit 15 as they pass through unit 15, it is preferred that an appropriate amount of diafiltration water be combined with the slurries 1A and 1B before the combination is passed through the ultrafilter. The amount of diafiltration water needed to prevent blinding of unit 15 is about 20,000 pounds/hour.

(10) This first phase of the process results in a first permeate stream 16 passing through the ultrafilter and a first retentate stream 17 that does not pass through the ultrafilter unit 15. The composition of these two streams is set forth in Chart 1 below.

(11) TABLE-US-00001 CHART 1-FIRST FILTRATION COMPOSITION MAKEUP FIRST PERMEATE FIRST RETENTATE CONSTITUENTS STREAM STREAM WATER 22,950 #/hour 2,550 #/hour PROTEIN 123 #/hour 7 #/hour FATS 105 #/hour 75 #/hour CARBOHYDRATES 265 #/hour 285 #/hour MINERALS 125 #/hour 15 #/hour TOTAL 23,568 #/hour 2,932 #/hour
The first retentate stream 17 is then transferred to a dryer 18 to remove the water from the stream 17. The resulting dried stream 19 is a high-fat fiber product that can be used as animal feed.

(12) Turning now to FIG. 2, the first permeate stream 16 is transferred by line 20 to ultrafilter unit 21. Unit 21 is preferably a 100,000 MWCO ultrafilter. Because of the size selection of the ultrafilter units, it is not necessary to add any additional diafiltration water. This second filtration process step results in a second permeate stream 22 and a second retentate stream 23. The composition of these two streams is set forth in Chart 2.

(13) TABLE-US-00002 CHART 2-SECOND FILTRATION COMPOSITION MAKEUP SECOND PERMEATE SECOND RETENTATE CONSTITUENTS STREAM STREAM WATER 21,802 #/hour 1,148 #/hour PROTEIN 101 #/hour 22 #/hour FATS 39 #/hour 66 #/hour CARBOHYDRATES 140 #/hour 125 #/hour MINERALS 116 #/hour 7 #/hour TOTAL 22,200 #/hour 1,368 #/hour
The second retentate stream 23 is then transferred to a dryer 24 to remove the water from the stream 23. The resulting dried stream 25 can serve as a milk or egg replacement product.

(14) Referring now to FIG. 3, the second permeate stream 22 is transferred inline 26 to ultrafilter unit 27. Unit 27 is preferably a 30,000 MWCO ultrafilter. Again because of the initial amount of diafiltration water, it is not necessary to add additional diafiltration water to the second permeate stream 22. This third filtration process step results in a third permeate stream 28 and a third retentate stream 29. The composition of these two streams is set forth in Chart 3.

(15) TABLE-US-00003 CHART 3-THIRD FILTRATION COMPOSITION MAKEUP THIRD PERMEATE THIRD RETENTATE CONSTITUENTS STREAM STREAM WATER 21,075 #/hour 727 #/hour PROTEIN 13 #/hour 88 #/hour FATS 36 #/hour 3 #/hour CARBOHYDRATES 137 #/hour 3 #/hour MINERALS 115 #/hour 3 #/hour TOTAL 21,376 #/hour 823 #/hour
The third retentate stream 29 is then transferred to a dryer 30 to remove the water from the stream 29. The resulting dried stream 29 can serve as a rice bran protein isolate.

(16) Referring now to FIG. 4, the third permeate stream is transferred inline 31 to a nanofilter unit 32. Unit 32 is preferably a 1,000 MWCO nanofilter. Again because of the initial amount of diafiltration water, it is not necessary to add additional diafiltration water to the third permeate stream 31. This fourth filtration process step results in a fourth permeate stream 33 and a fourth retentate stream 34. The composition of these two streams is set forth in Chart 4 below.

(17) TABLE-US-00004 CHART 4-FOURTH FILTRATION COMPOSITION MAKEUP FOURTH PERMEATE FOURTH RETENTATE CONSTITUENTS STREAM STREAM WATER 19,065 #/hour 2,010 #/hour PROTEIN 5 #/hour 8 #/hour FATS 4 #/hour 32 #/hour CARBOHYDRATES 63 #/hour 74 #/hour MINERALS 13 #/hour 102 #/hour TOTAL 19,150 #/hour 2,226 #/hour
The fourth retentate stream 33 is then transferred to a dryer 35 to remove the water from the stream 33. The resulting dried stream 36 can serve as neutraceutical product.

(18) Turning now to FIG. 5, the fourth permeate stream 34 is transferred inline 37 to a reverse osmosis unit 38. Unit 38 is preferably a 100 MWCO reverse osmosis filter. Again because of the initial amount of diafiltration water, it is not necessary to add additional diafiltration water to the fourth permeate stream 34. This fifth filtration process step results in a fifth permeate stream 39 of purified water that can then be dumped in a stream or other water body without further filtering or other treatment. A fifth retentate stream 40 is also formed. The composition of these two streams is set forth in Chart 5.

(19) TABLE-US-00005 CHART 5-FIFTH FILTRATION COMPOSITION MAKEUP FIFTH PERMEATE FIFTH RETENTATE CONSTITUENTS STREAM STREAM WATER 17,055 #/hour 2010 #/hour PROTEIN (AMINO & 0 #/hour 5 #/hour FATTY ACID) FATS (SUGARS) 0 #/hour 4 #/hour CARBOHYDRATES 0 #/hour 63 #/hour MINERALS 0 #/hour 13 #/hour TOTAL 17,055 #/hour 2,095 #/hour

(20) The fifth retentate stream 40 can be used as low molecular weight products.

(21) Referring to FIG. 6, the time to take each step in the process is set forth, including cleaning the filters to receive the next batch of rice bran slurry.

(22) Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions, and alterations can be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein maybe utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.