U.S. patent application number 09/840372 was filed with the patent office on 2001-08-16 for corn processing.
This patent application is currently assigned to Cargill, Incorporated a Delaware corporation. Invention is credited to Anderson, Stephan C., Ulrich, James F..
Application Number | 20010014750 09/840372 |
Document ID | / |
Family ID | 22942787 |
Filed Date | 2001-08-16 |
United States Patent
Application |
20010014750 |
Kind Code |
A1 |
Ulrich, James F. ; et
al. |
August 16, 2001 |
Corn processing
Abstract
A commercial-scale method for processing corn grain includes the
steps of flaking corn grain having a total oil content of at least
about 8% and extracting a corn oil from the flaked corn grain. Such
a method can be effectuated by processing the high oil corn grain
using methods and equipment typically used to process soybeans and
other similar oilseed types. In this way, processing plants that
flake oilseeds can be used to extract corn oil from corn.
Inventors: |
Ulrich, James F.; (Plymouth,
MN) ; Anderson, Stephan C.; (Minneapolis,
MN) |
Correspondence
Address: |
NANCY A. JOHNSON, PH.D
Fish & Richardson P.C., P.A.
Suite 3300
60 South Sixth Street
Minneapolis
MN
55402
US
|
Assignee: |
Cargill, Incorporated a Delaware
corporation
|
Family ID: |
22942787 |
Appl. No.: |
09/840372 |
Filed: |
April 23, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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09840372 |
Apr 23, 2001 |
|
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09249280 |
Feb 11, 1999 |
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Current U.S.
Class: |
554/14 ; 554/12;
554/13; 554/20; 554/21; 554/8; 554/9 |
Current CPC
Class: |
A23K 10/26 20160501;
C11B 1/10 20130101; C11B 1/06 20130101; A23K 10/24 20160501; A23K
10/20 20160501; A23J 1/144 20130101; C11B 1/104 20130101; C11B 1/04
20130101; B07C 2501/009 20130101 |
Class at
Publication: |
554/14 ; 554/8;
554/9; 554/12; 554/13; 554/20; 554/21 |
International
Class: |
C11B 001/00 |
Claims
What is claimed is:
1. A method for processing corn grain comprising the steps of: a)
flaking corn grain; and b) extracting an oil from said flaked corn
grain, said corn grain having a total oil content of at least about
8%.
2. The method of claim 1 wherein said corn grain is whole corn
grain.
3. The method of claim 2 wherein said corn grain is a cracked corn
grain.
4. The method of claim 1 wherein said corn grain has a total oil
content of at least about 14%.
5. The method of claim 1 wherein said corn grain has a total oil
content of at least about 12%.
6. The method of claim 1 wherein said corn grain has a total oil
content of at least about 10%.
7. The method of claim 1 wherein said corn grain has a total oil
content from about 12% to about 30%.
8. The method of claim 1 wherein said extracting step comprises
pressing said flaked corn grain.
9. The method of claim 1 wherein said extracting step comprises
solvent-based oil extraction of said flaked corn grain.
10. The method of claim 9 wherein said solvent is selected from the
group consisting of hexane, n-hexane, isopropyl alcohol, and
supercritical carbon dioxide.
11. The method of claim 9 wherein said solvent comprises
n-hexane.
12. The method of claim 9 wherein said extracting step produces a
miscella and a corn meal.
13. The method of claim 12 wherein said corn meal comprises a fiber
content of about 3%, a starch content of about 65%, and a protein
content of about 14%, at a moisture content of about 10%.
14. The method of claim 12 wherein said corn meal comprises a fiber
content of about 3%, and a protein content of about 14%, at a
moisture content of about 10%.
15. The method of claim 12 wherein said corn meal comprises a fiber
content of at least about 3%, at a moisture content of about
10%.
16. The method of claim 12 further comprising the step of
desolventizing said miscella to produce a corn oil.
17. The method of claim 16 wherein said corn oil has a phosphorous
content of less than about 500 parts per million.
18. The method of claim 16 wherein said corn oil has a free fatty
acid content of less than about 0.3%.
19. The method of claim 1 wherein said corn oil has a neutral oil
loss of less than about 2%.
20. The method of claim 1 wherein said corn oil has a light yellow
color.
21. The method of claim 16 wherein said corn oil has a yellow color
value ranging from about 60 to about 70 and a red color value
ranging from about 7 to about 10, as determined by American Oil and
Chemical Society method Cc 13b-93.
22. The method of claim 1 wherein said method is effective for
processing at least about 100 tons of corn per day.
23. The method of claim 1 wherein said method is effective for
processing from about 100 tons of corn per day to about 3,000 tons
of corn per day.
24. A method of selling corn seed comprising the steps of: a)
offering corn seed for sale, said corn seed effective for producing
corn grain having a total oil content of at least about 8%; and b)
advertising that said corn grain may be processed by flaking said
corn grain.
25. The method of claim 24 wherein step (b) further comprises
advertising that said flaking of said corn grain is effective for
producing a corn oil.
26. An article of manufacture comprising packaging material a label
accompanying said packaging material and seed corn contained within
said packaging material, wherein said seed corn is effective for
producing grain having a total oil content of at least about 8% and
wherein said label indicates that said grain can be processed by
flaking said grain and extracting an oil therefrom.
Description
FIELD OF THE INVENTION
[0001] The invention relates to processing corn. In particular, the
invention relates to processing corn to produce a corn oil and/or a
meal product.
BACKGROUND OF THE INVENTION
[0002] Corn, Zea mays L., is grown for many reasons including its
use in food and industrial applications. Corn oil is one of many
useful products derived from corn. Commercial processing plants
utilizing conventional methods for extracting corn oil typically
separate the corn seed into its component parts, e.g., endosperm,
germ, tipcap, and pericarp, and then extract corn oil from the corn
germ fraction.
[0003] Although the precise processing steps and types of equipment
vary somewhat from plant to plant, commercial corn processing can
be classified as either a wet milling or dry milling process.
Overall, wet milling is a sophisticated process involving many
steps. When isolating the corn oil fraction, corn seed is first
steeped in a water/sulfur dioxide (SO.sub.2) mixture at an elevated
temperature and then passed through degerminating mills to separate
out the corn germ. The wet milled germ contains about 50% oil,
which is then washed and dried.
[0004] Dry milling physically separates the germ and pericarp from
the rest of the corn seed. Dry milling can include tempering the
seed by adding water followed by drying, cooling, grinding, sifting
and aspirating the seed. Degermination is accomplished using a
Beall degerminator (TM), impact mills, granulators or other similar
degerminating equipment. The oil content of dry milled germ ranges
from about 18% to about 27% oil.
[0005] Corn oil is extracted from wet milled or dry milled germ
using physical expellers, solvent extractors, or a combination of
both. Wet milled germ typically undergoes a two-step extraction
because complete oil extraction is often unattainable using a
single extraction.
[0006] It is also conventional practice to condition corn germ
before oil extraction by adding moisture and heating the germ to
about 100.degree. C. Conditioning facilitates complete oil
extraction. Heating corn seed or germ before or during the
extraction, however, can detrimentally affect oil quality.
[0007] Corn oil extracted using wet milling methods has a dark
color and requires additional processing to achieve a useful oil.
Dry milling methods tend to produce a better quality oil.
Nevertheless, both dry and wet milling processes have drawbacks
that include high energy costs, expensive equipment, high
maintenance costs, and variable oil quality. Other corn oil
recovery methods have been attempted, but most have not proven to
be commercially feasible. Thus, there exists a need for improved
methods that alleviate one or more of the drawbacks associated with
conventional corn oil recovery methods.
SUMMARY OF THE INVENTION
[0008] In one aspect, the invention features a commercial-scale
method for processing corn grain that includes the steps of flaking
corn grain, and extracting an oil from the flaked corn grain. The
corn grain should have an elevated total oil content of at least
about 8%. The corn processing method may be effective for producing
corn oil and corn meals having defined characteristics.
[0009] In one embodiment, the corn grain has a total oil content of
at least about 14%. In alternative embodiments, the corn grain has
a total oil content of at least about 12%, at least about 10%, or
from about 12% to about 30%.
[0010] In another embodiment, the corn grain being flaked is whole
corn grain. In another embodiment, the corn grain is cracked corn
grain.
[0011] In another embodiment, the method of processing corn
includes an extracting step wherein the flaked corn grain is
pressed to extract an oil. Alternatively, the extraction step
exposes the flaked corn grain to solvent-based oil extraction.
Solvents used to extract miscible or soluble substances from the
flaked grain include hexane, n-hexane, isopropyl alcohol, and
supercritical carbon dioxide. Extracting steps can produce a
miscella and a corn meal.
[0012] In another embodiment, the corn meal resulting from corn
processing has a fiber content of about 3%, a starch content of
about 65%, and a protein content of about 14%, at a moisture
content of about 10%. In alternative embodiments, a subset of the
fiber content, starch content, and protein content are measured in
the resulting meal. For example, a corn meal may have a fiber
content of about 3%, and a protein content of about 14%, at a
moisture content of about 10%.
[0013] In another embodiment, miscella is desolventized to produce
a corn oil. The corn oil may be further refined. The corn oil may
have a phosphorous content of less than about 500 parts per
million, a free fatty acid content of less than about 0.3%, and/or
a neutral oil loss of less than about 2%.
[0014] In another embodiment, the corn oil has a light yellow
color. The color of the corn oil may have yellow and red colors.
The yellow color values may range from about 60 to about 70 and red
color values may range from about 7 to about 10, as determined by
American Oil and Chemical Society method Cc 13b-93.
[0015] In another embodiment, the corn processing method is
effective for processing at least about 100 tons of corn per day or
for processing from about 100 tons of corn per day to about 3,000
tons of corn per day.
[0016] In another aspect, the invention features a method of
selling corn seed that includes the offering corn seed for sale, or
actually selling corn seed, wherein the corn seed can produce corn
grain having a total oil content of at least about 8% and
advertising that the corn grain may be processed by flaking the
corn grain. In one embodiment, the method includes advertising that
the flaking of the corn grain is effective for producing a corn
oil.
[0017] In another aspect, the invention features a method for
marketing corn seed that includes making, using, selling offering
for sale, or otherwise providing corn seed wherein the corn seed
can produce corn grain having a total oil content of at least about
8% and advertising that the corn grain may be processed by flaking
the corn grain. In one embodiment, the method includes advertising
that the flaking of the corn grain is effective for producing a
corn oil.
[0018] In another aspect, a novel method of doing business
comprises the steps of buying, purchasing, or offering to buy corn
grain having a high oil content for the purpose of processing the
purchased grain by flaking the grain and extracting an oil
therefrom. In one embodiment, the method includes advertising that
a facility flakes high oil corn grain.
[0019] In another aspect, the invention features an article of
manufacture that includes packaging material, a label accompanying
the packaging material and seed corn contained within the packaging
material. The packaged seed corn is effective for producing grain
having a total oil content of at least about 8%. Labels associated
with the article of manufacture indicate that the grain produced by
the corn seed can be processed by flaking the grain and extracting
an oil therefrom.
[0020] Advantages of the invention include commercially feasible
methods for extracting an oil from corn without having to steep the
corn or heat the corn to elevated temperatures. Corn oil can be
extracted from whole corn grain without having to separate the corn
grain into its component parts. The corn oil produced can be of a
better quality than the oil produced by known wet-milling methods,
which currently process about 50,000,000 tons of corn grain per
year world wide. Dry milling, on the other hand, accounts for about
3,000,000 tons of corn grain per year. The crude oil can require
fewer processing steps. Oil loss during the oil processing can be
minimized. Products other than corn oil can still be obtained.
Processing equipment used for other seed types, such as soybeans,
can be utilized for multiple grains.
[0021] Unless otherwise defined, all technical and scientific terms
and abbreviations used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which this
invention pertains. Although methods and materials similar or
equivalent to those described herein can be used in the practice or
testing of the present invention, suitable methods and materials
are described below. All patents, publications and official
analytical methods referred to herein are incorporated by reference
in their entirety. Additional features and advantages of the
invention will be apparent from the following description of
illustrative embodiments of the invention and from the claims.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] It has been discovered that corn oil can be rapidly and
efficiently extracted on a commercial-scale from corn grain having
increased oil content by flaking the corn grain and extracting a
corn oil. Useful corn grain for the novel flaking oil processing
method has a total oil content greater than about 8%. Increases in
the oil content of corn grain may increase flaking efficiency
during processing. Suitable flaking equipment and methods include
conventional flaking equipment and methods used for flaking soybean
and other similar oilseed types. Suitable extracting equipment and
methods may include conventional methods used for extracting oil
from soybean flakes and other similar oilseed types.
[0023] Oil extraction methods for seeds or grain other than corn,
such as soybeans, sunflowers, rapeseed, and canola, exclude some of
the conventional corn oil processing steps. For example,
preprocessing of soybeans for oil extraction includes drying,
cracking, and aspirating the soybeans to separate the meats from
the seed hulls. The meats are then crushed into thin flakes by
passing the meats through flaking rollers without removing the germ
or embryo. Oil is then extracted from the flaked meats using
physical or chemical extraction methods.
[0024] Corn seed or "grain" harvested from many types of corn
plants are useful in the invention. Such corn plants may be
hybrids, inbreds, or a population. Useful grain types include, for
example, flint corn, popcorn, flour corn, dent corn, white corn,
and sweet corn. The grain can be in any form including whole corn,
cracked corn, or other processed corn or parts thereof that are
amenable to flaking.
[0025] Commercial-scale methods and equipment are sufficient for
extracting corn oil from at least about 100 tons of corn per day.
In some embodiments, the capacity of commercial-scale operations
ranges from about 100 tons of corn per day to about 3000 tons of
corn per day, or the capacity ranges from about 700 tons of corn
per day to about 1700 tons of corn per day. Commercial-scale
operations that process greater than about 3000 tons of corn per
day are also sufficient.
[0026] Useful corn grain has a total oil content greater than about
8%, which is greater than the total oil content of current
commodity grade number 2 yellow dent corn, which has an oil content
of about 3% to about 5%. Additionally, the total oil content of
corn grain suitable for the invention can be, for example, grain
having an oil content of at least about 9%, at least about 11%, at
least about 12%, at least about 14%, at least about 18%, at least
about 20%, from about 8% to about 20% oil, from about 10% to about
30% oil, or from about 14% to about 30%, and values therebetween.
Although the oil content can be determined at any moisture content,
it is acceptable to normalize the oil content to a moisture content
of about 15.5%.
[0027] Corn grain having an increased total oil content can be
identified and obtained using any method. For example, corn ears
can be selected using a near infrared (NIR) oil detector to select
corn ears having corn kernels with elevated oil levels or
individual corn kernels can be selected using a NIR detector.
Selecting individual ears and/or kernels having an elevated oil
content may not be cost effective. Preferably, corn seed producing
corn plants that yield grain having elevated total oil
concentrations can be planted and harvested using known farming
methods. Methods for developing corn inbreds, hybrids, and
populations that generate corn plants producing grain having
elevated oil concentrations are known.
[0028] The moisture content of the corn grain can affect the
flaking process. It may be necessary to adjust the moisture content
of the corn grain to about 10% before flaking the seed. Optimizing
the grain moisture content to facilitate efficient processing is
within the knowledge of those of ordinary skill in the art.
[0029] The oil content of grain, including the fat content of a
meal extracted from the grain, can be determined using American Oil
and Chemical Society Official Method, 5th edition, March 1998,
("AOCS method") Ba 3-38. AOCS method Ba 3-38 quantitates substances
that are extracted by petroleum ether under conditions of the test.
The oil content or concentration is the weight percentage of the
oil with respect to the total weight of the seed sample. Oil
content may be normalized and reported at any desired moisture
basis.
[0030] Unlike conventional oilseed flaking processing in which the
hull component of the seed is removed before flaking, pericarp
components of corn grain need not be removed before flaking, i.e.,
whole corn or cracked corn can be flaked. Corn grain is flaked to
any useful size. For example, corn grain is flaked in one or more
passes through flaking rollers to produce flakes having a final
thickness of about 0.01 inches (0.25 mm), although other
thicknesses may also be used. Useful flake thicknesses may depend
on external limiting parameters such as the oil content of the
corn, the moisture content, the corn type, e.g., dent or flint, and
the oil extractor type.
[0031] Commercial-scale oilseed flaking and oil extraction methods
as well as commercial-scale processing plants are known. In
particular, suitable flaking and oil extraction methods include the
methods and plants used for processing soybeans and similar oilseed
types. Useful commercial-scale oilseed flakers can be obtained from
French Oil Mill Machinery Company, Piqua, Ohio USA 45456-0920, ph.
(937)-773-3420; Roskamp Champion, Waterloo, Iowa; Buhler, based in
Switzerland and having offices in Plymouth, Minn. USA;
Bauermeister, Inc., Germany; and Consolidated Process Machinery
Roskamp Company, on the world wide web at
http://www.cpmroskamp.com.
[0032] Corn oil is extracted from flaked grain in one or more
extraction steps using any extraction method. Preferably,
substantially all the oil is extracted in a single extraction step.
Useful extraction methods include solvent extraction, hydraulic
pressing, and expeller pressing. Useful solvents for solvent
extraction can include hexane, n-hexane, isopropyl alcohol,
supercritical carbon dioxide, and other similar solvents. For
example, corn oil can be extracted from flaked grain using an
n-hexane solvent extractor. Solvent extractors can include both
percolation and immersion type extractors.
[0033] Substances exiting solvent-based extractors are referred to
as wet flakes and miscella. Miscella is a mixture of extracted oil
and solvent. The wet flakes are the material that remains after
some or all of the solvent-soluble material has been extracted. Wet
flakes also contain a quantity of solvent. Solvent is reclaimed
from both miscella and wet flakes using known methods. For example,
heat is applied to the wet flakes or miscella under a vacuum.
Desolventized miscella is referred to as a crude oil that may be
stored and/or undergo further processing. Crude oil obtained
according to the invention may be refined to produce a final oil
product. Methods for refining crude oil to obtain a final oil
product are known to those of ordinary skill in the art. Crude oil
isolated using the flaking methods described herein is of a high
quality and requires fewer processing steps than is typically used
in wet milling methods for processing corn grain to obtain corn
oil.
[0034] Wet flakes are desolventized, dried and sized for storage
and/or sale as a corn meal using methods known to those of ordinary
skill in the art. The corn meal may also be mixed with other meal
types or feedstuffs to create a complete feed or other meal or feed
types.
[0035] Corn oil or meal quality is determined by evaluating one or
more quality parameters such as the oil yield, phosphorous content,
free fatty acid percentage, the neutral oil loss percentage, color,
meal fat, fiber percentage, starch percentage, protein content, and
moisture content. Any method can be used to calculate one or more
of the quality parameters for evaluating the oil or meal
quality.
[0036] The phosphorous concentration of crude oil can be determined
using AOCS method Ca 12-55. AOCS method Ca 12-55 identifies the
phosphorous or the equivalent phosphatide content of an oil by
ashing an oil sample in the presence of zinc oxide, followed by the
spectrophotometric measurement of phosphorous as a blue
phosphomolybdic acid complex. AOCS method Ca 12-55 is applicable to
crude, degummed and refined vegetable oils. The phosphorous
concentration is converted to phospholipid concentration, i.e., gum
concentration, by multiplying the phosphorous concentration by
30.
[0037] The free fatty acid percentage of an oil can be determined
using AOCS method Ca 5a-40. AOCS method Ca 5a-40 identifies the
free fatty acids existing in the oil sample. AOCS method Ca 5a-40
is applicable to all crude and refined vegetable oils, marine oils
and animal fats. The neutral oil loss during processing is
determined by adding the gum percentage and the free fatty acid
percentage together.
[0038] Oil color can be determined using AOCS method Cc 13b-45.
AOCS method Cc 13b-45 identifies the color of an oil sample by
comparing the oil sample with known color characteristics. AOCS
method Cc 13b-45 is applicable to fats and oils provided no
turbidity is present in the sample. Color values are quantitated by
determining a red color value and a yellow color value using the
AOCS method Cc 13b-45. Typically, crude corn oil isolated using wet
milling methods has a red color value ranging from about 15 to
about 20 and a yellow color value ranging from about 70 to about
80. Typically, crude corn oil isolated using dry milling methods
has a red color value ranging from about 7 to about 10 and a yellow
color value ranging from about 60 to about 70.
[0039] Color values are evaluated qualitatively by visual
inspection of an oil. Typically, visual inspection results in an
oil being classified as a light oil or a dark oil compared to a
known oil color. For example, it is typical for crude oils isolated
using wet milling techniques to be considered dark brown by visual
inspection whereas oils isolated using dry milling techniques are
considered lighter yellow. Corn oils isolated using flaking methods
described herein have oil colors that are qualitatively considered
light and quantitatively similar to crude corn oil color values for
corn oils isolated using dry milling techniques.
[0040] Corn meal isolated using flaking methods as described herein
can be a low fat corn meal. Several important quality parameters
for oilseed meals include the fat, starch, protein, and moisture
content of the resulting meal. Methods for evaluating quality
parameters of oilseed meals, including corn meals, are known.
[0041] Corn meals derived using different methods or isolated at
different times are compared by normalizing the meals to a common
moisture content. The moisture content of an oilseed protein
concentrate, such as a corn meal or whole corn, is determined using
AOCS method Ba 2b-82. The crude fiber content of corn meal is
determined using AOCS method Ba 6-84. AOCS method Ba 6-84 is useful
for grains, meals, flours, feeds and all fiber bearing material
from which the fat can be extracted leaving a workable residue.
Crude protein content of corn meal is determined using AOCS method
Ba 4e-93. The starch content of corn meal is determined using the
Standard Analytical Methods of the Member Companies of the Corn
Refiners Association Incorporated, 2d Edition, Apr. 15, 1986,
method A-20 ("Corn Refiner's method A-20").
[0042] It is to be understood that the analytical methods provided
herein are illustrative examples of useful methods for computing
various quality parameters for the oils and meals described herein.
Other suitable methods are known and may be used to compute the
quality parameters disclosed and claimed herein.
[0043] Novel methods for processing corn described herein
facilitate a novel method for doing business, which can include the
following steps. Corn seed that is effective for developing into a
corn plant that produces corn grain having a total oil content of
at least about 8% is made, used, sold or offered for sale.
Advertisements, marketing strategies, or other suitable promotions
concerning the corn seed are disseminated to the relevant audience.
The advertisements indicate that corn grain harvested after
planting the corn seed can be processed using flaking techniques or
methods. The advertisements can further indicate that the flaking
methods facilitate extracting a corn oil or can indicate that
suitable flaking methods include methods that are used for
processing oilseeds such as soybeans. Such a method is useful for
marketing or selling corn seed to consumers in regions where
oilseed processing plants that utilize flaking methods are
physically located. The relevant audience includes farmers, seed
corn dealers, oilseed processors, and other persons involved in the
oilseed industry. Suitable advertisements include radio and
television advertisements, labels or other indicia present on
packages of corn seed, promotional meetings, random or directed
mailings, hand bills, and any other form of communication directed
to the relevant audience.
[0044] In another aspect, a novel method of doing business
comprises the steps of buying, purchasing, or offering to buy corn
grain having a high oil content for the purpose of processing the
purchased grain by flaking the grain and extracting an oil
therefrom. In so doing, a business may advertise that it is a
facility that flakes high oil corn grain. In particular, the
facility may flake corn for extracting corn oil and/or producing
corn meal.
[0045] An article of manufacture can include packaging material and
seed corn contained within the packaging material. Such seed corn
produces a corn plant that yields corn grain having an oil content
greater than about 8% which may be processed by flaking the corn
grain and extracting an oil. Also included with the packaging
material is a label or package insert that indicates that an oil
can be extracted from the resulting corn grain by flaking the corn
grain and extracting an oil or described herein. Any known
packaging and printing method may be used to prepare the packaging
material of the article of manufacture.
EXAMPLE 1
Processing High Oil Corn Using A Flaking Method
[0046] Shelled kernels of individual ears of yellow dent corn were
screened for a total oil content greater than about 7% oil using a
Perten bulk near infrared (NIR) seed tester (TM) (model 9100-H.F)
Perten Instruments, P.O. Box 7398, Reno, Nev. 89510. Kernels from
the ears having at least a 7% oil content were screened further for
individual kernels having an oil content of at least 13% oil in a
Brimrose seedmeister (TM) single kernel NIR tester (Brimrose Corp.,
Baltimore, Md.). The kernels were stored at a moisture content of
about 13.5%. At the time of processing, the moisture content of the
seed was about 10%.
[0047] A bench scale flaking apparatus containing a two inch
stainless steel rod and plate was used to flake the whole corn
grain. The whole corn grain sample was passed through the rollers
four times to obtain a final flake thickness of about 0.01 inches.
A miscella was extracted from the flaked corn grain using hot
(60-65.degree. C.) n-hexane and a Kimble (TM) model 585050 Soxhlet
extractor. The resulting miscella and corn meal were desolventized.
The miscella was desolventized by heating the miscella to
70.degree. C. under a vacuum of 25 inches mercury. The corn meal
was desolventized according to AOCS method Ba 2a-38.
[0048] The total recovered oil was determined to be 14.74% of the
whole corn grain sample. The phosphorus content of the
desolventized crude oil was determined to be 365 parts per million
(ppm) using AOCS method Ca 12-55. The phospholipid concentration
was determined to be 1.095% (0.0365%* 30). The free fatty acid
content was determined to be 0.2% using AOCS method Ca 5a-40. The
neutral oil loss during processing was determined to be 1.3%
(1.095%+0.2%). Using the same methods, crude oil extracted from
normal, i.e., 3-4% total oil content, corn grain using conventional
wet milling methods can be expected to have a phosphorous content
from about 600 ppm to about 800 ppm, a free fatty acid
concentration from about 0.5% to about 1.0 percent, and a neutral
oil loss during processing ranging from about 3% to about 4%.
[0049] The color of the crude oil was visually evaluated and
determined to be a light yellow color compared to a crude oil
isolated using conventional wet milling methods, which was a dark
brown color.
[0050] The desolventized corn meal was characterized using AOCS
methods Ba 3-38, Ba 2b-82, Ba 6-84, and Ba 4e-93, and Corn
Refiner's Method A-20. When normalized to a 10% moisture content,
the corn meal had a 3.2% fiber content, a 65% starch content, and a
14% protein content. Meal fat was determined to be 1.07% using AOCS
method 3-38. For comparison, corn gluten feed created using
conventional wet milling methods and normalized to a 10% moisture
content can be expected to contain an oil content of about 4%, a
protein content of about 20%, and a fiber and other carbohydrate
content of about 60%. Also for comparison, corn gluten meal created
using conventional wet milling methods and normalized to a 10%
moisture content can be expected to contain an oil content of about
3%, a protein content of about 60%, and a fiber and other
carbohydrate content of about 22%.
[0051] To the extent not already indicated, it also will be
understood by those of ordinary skill in the art that any one of
the various specific embodiments herein described and illustrated
may be further modified to incorporate features shown in other of
the specific embodiments.
[0052] The foregoing detailed description has been provided for a
better understanding of the invention only and no unnecessary
limitation should be understood therefrom as some modification will
be apparent to those skilled in the art without deviating from the
spirit and scope of the appended claims. As such, other aspects,
advantages, and modifications are within the scope of the following
claims.
* * * * *
References