Note: Descriptions are shown in the official language in which they were submitted.
1~77864
LIPID ENROBED FODDER RATIONS
AND MANUFACTURE THEREOF
RELATED APPLICATION
Hydrosyn Systems, Inc. and James P. Cox
International Application No. PC~/US 83/01869, filed
November 29, 1983, in the United States Receiving
Office, for "Lipid Pelletization Methods, Apparatus and
Products~, publi~hed 21 June, 1984 under International
Publication No. WO 84/02255.
BACRGROUND OF THE INVENTION
~echnical Eield
The present invention relates generally to
fodder ration~ used as feedætuffs for husbanded animal6
and the like--e.g., ruminants such as cattle, sheep,
giraffes, deer, camels and swine; zoo animals; horses;
fowl; canine or feline pets; fish; shrimp; birds;
etc.--and, more particularly, to improved feed rations
and methods of manufacture thereof which permit of
distribution of feed particles and/or pellets having
predetermined, and controllable, percentages of
stabilized adry~ lipid~ incorporated therein to such
husbanded animals and the like as a dietary feed
supplement wherein the dry, stabilized lipid content of
the thus treated feed ration may readily range up to,
or even in exce6s of, 20~ by weight of the feed
ingredient per se without danger of rancidity, pellet
or particle agglomeration and/or damage to the
integrity of the feed rations themselves.
More 6pecifical1y, the present invention
relates to the application of controllable amounts of
1~778~4
lipids to a wide range of otherwise conventional and
commercially available animal feedstuffs such, for
example, as grains, alfalfa, and mixtures of feedstuffs
so as to encapsulate the conventional pelletized dry
feedstuff and/or the constituent ingredients thereof in
a lipid emulsion which is allowed to "set" to form dry,
stabilized, edible pelletized feed products wherein
either the pellets or the feed particles sometimes used
to form pellets have protective outer lipid shells that
may constitute any desired and preselected proportion
of the total weight of the overall composite feed
ration ranging, for example, from a few percent of the
total weight of the feed ration to up to 20%, 25~, or
more of the total weight of the feed ration. The
conventional feedstuff may, if desired, be preheated
prior to application of the lipid emulsion so as to
reduce its water of hydration level to a desired point
below equilibrium, thereby permitting the water content
of the emulsion to e~uilibriate with the thus
superheated feedstuff so as to reduce, and in some
cases eliminate, the need for any significant
subsequent drying steps.
Background Art
As pointed out in greater detail in the
aforesaid Related Application, the value of fats, oils
(other than essential oils), and greases (other than
hydrocarbon and/or petroleum-based materials), herein
generically referred to as "lipids~, as a nutritional
feed supplement for virtually the entire gamut of the
animal world--including, for example: ruminants such
as cattle, sheep, girafes, deer, camels and swine; zoo
1'~77#~4
animals; horses; fowl; canine or feline pets; fish;
shrimp; birds; etc.--has long been recognized.
~nfortunately, however, the very nature of such lipids,
which are commonly in liquid form or whlch exude or
bleed liquified oil and/or grease exudates,
particularly at elevated temperatures, has served to
minimize their mass distribution and/or use as a feed
supplement. Thus, the tendency of lipids to become
rancid and spoil when subjected to oxidants serves to
impose severe limitations on the shelf life of dry feed
products incorporating such lipids. Moreover, lipid
materials, when admixed with grain and similar dry feed
products, are not only subject to rancidity but, in
addition, they are temperature sensitive, tend to clump
or otherwise agglomerate, and to disperse non-uniformly
through such conventional feed products; and,
consequently, they create severe packaging and handling
problems.
~evertheless, extensive efforts have
heretofore been made to incorporate lipids in, and/or
apply lipids to, pelletized animal feed products; but,
prior to the advent of the present invention and the
invention disclosed and claimed in the aforesaid
Related Application, such efforts have not met with
commercial success. Thus, not only have the lipid
treated pellets been subject to rancidity and spoilage
unless treated with antioxidants at attendant increased
expense and process complexity but, additionally, the
propensity for such products to weep and bleed lipid
exudates has created an agglomeration and handling
problem that has continued to plague the industry.
Moreover, while dietary considerations will commonly
77864
--4--
mandate the inclusion of a lipid dietary supplement in
husbanded animal feed rations which can range from only
a few percent to percentages on the order of 20~ or
more lipids by weight, conventional pelletized food
products are unable, structurally, to carry more than
about 7~ lipids by weight, at whlch point they lose
their ~tructural integrity and begin to crumble. Thus,
excluding the lipid-carrying capacities of animal feed
rations as disclosed and claimed herein and in the
aforesaid Related Application, the feed industry has
generally found that the lipid content of commercially
available dry feed products must be limited to only a
few percent lipids by weight, since dry feed
ingredients having higher percentages are subject to
the formation of lipid exudates which: i) seriously
detract from the free flowability of the dry feed
product; ii) promote rapid rancidity and spoilage in
the absence of antioxidants; and iii), cause pelletized
feedstuffs to rapidly disintegrate as the lipid content
approaches and exceeds on the order of 7~ lipids by
weight.
One approach that has heretofore been
attempted has involved the use of "spaghetti-type"
extrusion equipment to form kibble-type animal feed
rations--rations which desirably will include a lipid
dietary supplement. Efforts to add the lipids in any
significant quantities to the ingredients fed into the
extrusion equipment have proven unsuccessful for a
number of reasons. Thus, the heat generated in the
extrusion process tends to liquify the lipid which is,
therefore, in effect, expressed from the ~dry" feed
ingredients in the extrusion process itself. To the
1~77864
extent that some proportion of the lipid is extruded
with the feed ingredients to form a kibble, the lipid
content thereof tends to form a liquid lipid exudate
which is highly undesirable--particularly in those
instances where the feed product is bagged and a
plurality of bags are stacked one upon the other--that
iB, the very weight of the feed product tends to
express the lipids from the lowermost kibbles. To
eliminate the problem of expressing the lipid from the
feed ingredients in the extrusion process, attempts
have been made to spray the lipid materials onto the
exterior surfaces of the kibble-type ration following
extrusion. In either case, however, the lipid
constituent remains unbound; and, therefore, tends to
coat the surface of the kibble ration with an oily or
greasy surface film. Such films are not only subject
to rancidity and spoilage, severely limiting the
product's useful shelf life; but, additionally, the
lipid surface films cause the extruded kibbles to
agglomerate, interfering with their free-~lowability at
the point of consumption, and they tend to impregnate
the bags and/or other packaging materials employed,
rendering them unsightly, damaging their integrity, and
producing other undesirable handling and health
conditions including, but not limited to, attractin~
rodents, vermin and the like.
~ umerous prior art efforts to provi~e an
effective, commercially viable, animal feed product
having a lipid feed dietary supplement contained
therein are described in the aforesaid ~elated
Application; but, each such approach has proven
unsuccessful from a commercial standpoint either
1~77864
because it has not proven cost-effective, the lipid
content of the feed product was too limited, and/or the
lipid material tended to weep, causing product
agglomeration seriously detracting from handling
characteristics, and/or caused spoilage due to
rancidity. Such problems, however, have been overcome
by adopting the processes disclosed in such Related
Application for forming dry, integral feed pellets
wherein the lipid material constitutes an integral,
generally homogeneous, constituent of the feed pellet
ingredients both prior to and after pelletization.
Nevertheless, there has continued to be a need for a
simple, cost-effective process for adding a lipid
dietary supplement in useful ranges of percentage
lipids by weight to existing dry feed pellets and/or
particles in sùch a manner as to meet the variou6
dietary requirements of a wide range of husbanded
animals; yet, at the same time, in a manner which does
not interfere with the free flowability and/or ease of
han~ling of such commercially available dry pellets
and/or particles and which does not subject such
rations to spoilage.
As indicated above, prior to the advent of
the invention disclosed and claimed in the aforesaid
Related Application, the foregoing problems had
continued to plague the industry despite extensive
expenditures of time and money in attempts to resolve
the problems and to provide a system suitable for
widespread mass distribution of lipid-type food
supplements. Research directed to attempts to provide
solutions to the problems has been conducted and/or
sponsored by a wide range of institutions including,
~778~i~
for example, the Fats And Proteins Research Foundation,
Inc. of Des Plains, Illinois, as well as at innumerable
university-based research facilities, principally in
the agricultural fields. For example, it has been
5 known for years that lipids can be absorbed in a wide
variety of edible absorbant host carriers or support
matrices such as rice, puffed rice or wheat, wheat
middlings, wheat bran, beet pulp, alfal~a meal, corn
cobs, bees wings, edible clays or earths, etc. See,
10 for example: Robison, U.S. Pat. No. 1,997,083 (oil
treated bird seeds and other cereal products); Clayton,
U.S. Pat. No. 2,991,178 (oil treated beans and seeds);
Lewis, U.S. Pat. No. 3,257,209 (soybean oil meal);
Pruckner et al, U.S. Pat. No. 3,340,065 (fat containing
15 edible bleaching earth); and, Hoffman, U.S. Pat.
No. 3,620,755 (soybean meal impregnated with edible
oleaginous materials and cooked in boiling water).
Unfortunately, tbe foregoing approaches, and
many similar approaches contemplating the impregnation
20 of an edible host carrier, have not met with acceptance
or widespread con~nercial usage for a wide variety of
reasons. For example, the host carrier itself renders
the product suitable for use on a highly limited
species-specific basis. The problems of stability,
25 rancidity, temperature sensitivity, and mess in
handling resulting from exudates, remain. The carrier
itself often ca~nprises substantially in excess of 50%
of the weight and bulk of the thus treated feed
product, not only limiting the amount of nutritional
30 lipid values that can be fed to various types of
animals but, also, significantly increasing the cost of
distribution. The resulting impregnated carriers often
1~77864
--8--
have wet or oily surface coatings and are generally not
free-flowing. Moreover, many of such carriers--for
example, rice--are simply too expensive to permit
widespread usage as animal feeds.
Another approach has involved relatively
expensive and highly complex processes for converting
fat or similar lipids to powdered dry form. Typical of
this approach are the systems disclosed in Campbell,
Jr. et al, U.S. Pat. No. 3,514,297, Grolitsch, U.S.
Pat. ~o. 3,892,880, and Nappen, U.S. Pat.
No. 4,232,052. However, such powdered lipid products
are prohibitively expensive for use as an animal food
supplement.
In the mid-1970's, the widespread research
and experimentation then underway led to the purported
"solution" disclosed in Scott et al, U.S. Pat.
No. 3,925,560 and in Rawlings et al, U.S. Pat.
No. 4,042,718. Thus, in these patents, the patentees
disclose systems wherein lipids are encapsulated in
protective protein-aldehyde complex coatings to produce
concentrated high fat, dried, particulate, free-flowing
compositions. While the efforts of Scott et al and
Rawlings et al, for the first and only time prior to
the advent of the invention disclosed and claimed in
the aforesaid Related Application, produced "dry
pellets" or particles characterized by a high lipid
content which were contemplated as having utility for
animal feed products, unfortunately the systems have
met with no commercial acceptance because, if for no
other reason, the aldehyde constituent was, and is, a
known carcinogen and, consequently, the resulting
product was not, and cannot be, approved for use as an
animal ~eed supplement.
1~77~64
In U.S. Pat. No. 4,216,234, Rawlings et al
disclose a particulate composition formed by a
dispersion or emulsion of globules of nutrient lipids
within an aqueous albumin-containing medium which is
thereafter formed into a gel and dried to form the
composition--an arrangement characterized by a
relatively low percentage of lipid content within the
particulate product. In U.S. Pat. No. 4,217,370,
Rawlings et al disclose a process for making
lipid-containing foodstuffs comprising solublizing
particulate proteinaceous matter, admixing a lipid
material so as to form an emulsion, and contacting the
emulsion with an effective amount of a pH adjusting
agent to lower the pH to its isolectric point, thereby
aggregating the protein and simultaneously
microencapsulating the lipid. Again, the fat content
of the resulting product tends to be relatively low.
Moreover, both approaches are technically complex from
a production standpoint, prohibitively expensive,
present severe potential bacterial problems and,
indeed, can result in products having carcinogenic
properties.
Many prior art patents can be found whi~h
relate in general to the fonmation of gelatinous food
products by the interaction of alginates with various
metal salts and, particularly, with salts of calcium
such as calcium carbonate. Typical of these patents
are: Steiner, U.S. Pat. No. 2,441,729; Gi~sen, U.S.
Pat. No. 2,918,375; Freedman, U.S. Pat. No. 3,349,079;
and, Miller et al, U.S. Pat. No. 3,455,701. In
general, these patents disclose relatively slow
gelation processes which generally require on the order
1~778~4
--10--
of ten minutes for the calcium solution to cause the
alginate to form a soft gel. A similar disclosure
appears in an article authored by T. R. Andrew and
W. C. MacLeod, ~pplication And Control Of The
5 Algin-Calcium Reaction, FOOD PRODUCT DEVELOPMENT,
August-September 1970, at pp. 99, 101, 102 and 104. In
this article, the authors discuss the fonmation of
various types of artificial food products using a
sodium alginate solution which can be slowly gelled by
dispersion in an aqueous calcium salt solution or which
can be instantaneously gelled by dispersion into a 10%
solution of calcium chloride. It is stated that a
mixture of an algin syrup with sugar, colorings,
flavors, etc., can be deposited in a calcium chloride
bath "...to form spheres which look like fruit or
vegetable pieces...~ or "...caviar...~ (p. 104). None
of the foregoing relate, however, to systems intended
for or capable of pelletizing lipids per se and/or
binding lipids with a coagulant to render such lipids
"dry~, stable and essentially temperature insensitive.
In Peschardt, U.S. Pat. No. 2,403,547, the
paten~ee proposes forming a viscous solution comprising
100 parts by weight of water, 20 parts by weight of
glucose, and sodium alginate comprising from 1% to 2%
by weight of the final solution, to which any desired
optional colorings or flavorings may be added. To make
spheroidal-shaped objects such as ~cherries~, the
patentee proposes extrusion of the foregoing basic
stock as ~detached blobs" from extrusion nozzleæ into
an aqueous solution of calcium chloride which is stated
can ran~e from "...as little as 1% or 3% or as much as
10% or more calcium chloride in the setting bath...~
1~77864
tCol. 2, 11. 44-46). Peschardt further suggests that
shapes and forms other than spheroidal can be obtained
by charging the basic alginate stock into mold
recesses, and then depositing the pre-molded shapes of
viscous stock into the setting bath. There is no
teaching in Peschardt of the use of lipid ingredients.
Although the use sf algin-like coagulant~ to
form dry, stable, discrete, solid pellets or particles
containing high concentrations of lipids had not, prior
to the advent of the invention disclosed in the
aforesaid Related Application, been contemplated, it
has long been recognized that algins are suitable for
use as barrier layer6 in forming gel-like lipid
emulsions that can be utilized as a part of a complex
overall mixed ingredient system in a wide range of food
analogs. Such systems are disclosed in, for example,
Hawley, U.S. Pat. No. 3,658,550 wherein an artificial
adipose tissue is produced by reacting an aqueous
solution of an alkali salt of alginic acid and a
retarding agent with a fat dispersion of an alkaline
earth metal salt to form an alginate gel matrix with
the liquid fat entrapped therein in small discrete
droplets or globules which are then slowly released by
rupture of the walls enclosing the droplets during
cooking to baste a simulated analog meat product--i.e.,
the alginate/meat matrix comprises a honeycomb-like
structure containing liquid fat entrapped in the
interstices of the honeycomb-like matrix.
Similarly, Feldbrugge et al, U.S. Pat.
No. 3,919,435 discloses a meat analog formed from a
vegetable protein gel precursor that has incorporated
therein animal fatty tissue and/or vegetable oil with a
,~77864
--12--
thermostable, polymeric carbohydrate gel. In this
disclosure, as in ~awley, supra, fat is employed simply
as one ingredient in an overall meat analog system;
and, there is no disclosure for, nor intention of,
forming integral, discrete, dry, solid, lipid particles
or pellets per se and/or lipid enrobed particles or
pellets per se. Algin, in effect, simply forms a
barrier between protein and fat fractions in a meat
analog containing on the order of only 5~ to 30~ by
weight of fat and/or vegetable oil.
Other similar disclosures are found in:
Kofsky et al, U.S. Pat. No. 3,862,336 which discloses
an animal food product comprising a dried proteinaceous
food substance, an aqueous matrix including a water
soluble colloidal binding and gelling agent, and a
water soluble, low molecular weight, solid, liquid, or
mixture thereof, and which can contain relatively low
concentrations of fat; and, Baugher, U.S. Pat.
No. 4,098,913 which contemplates the formation of
regularly shaped gelled fat particles made by admixing
a triglyceride fat or Oil and a gelling agent which is
then heated and cooled while being agitated to form
gelled particles that can be incorporated into meat
analogs.
Other patents of general interest include:
Strums et al, U.S. Pat. No. 3,991,224 (a whipped food
product and process for forming the same); Goryaev et
al, U.S. Pat. No. 4,007,248 (a dried fat emulsion
concentrate); Schroeder et al, U.S. Pat. No. 4,027,043
~an animal feed supplement in solid, range block form
and said to contain fats); British Pat. No. 586,157 (a
process for forming simulated fruit and the like from
1~77~;4
--13--
alginates); French Pat. No. 874,977 (an alginate based
gel emulsion to form spreadable food analogs); and,
French Pat. No. 2,087,852 lan alginate based fruit skin
analog and an encapsulated oil-in-water emulsion--i.e.,
a liquid emulsion within an outer capsule formed of
algin--suitable when ruptured for basting meat).
Still other patents of miscellaneous interest
pertaining to alginate based compositions and processes
for making food products and the like, but which do not
contemplate any significant, if any, lipid content,
include: U.S. Pat. Nos. 2,809,893-Poarch et al;
2,965,498-~artwig et al; 2,973,274-Langmaack;
3,060,032-Glicksman; 3,362,831-Szezesniak; and,
3,650,766-Smadar.
In general, it has been found that despite
the efforts of a large number of researchers over a
prolonged period of time, as exemplified by the
foregoing publication and patents, prior to the advent
of the present invention and the invention disclosed
and claimed in the æ oresaid Related Application, no
simple, economical system had been developed for
delivering a lipid, per se, or high lipid concentration
particles, in integral, dry, solid, highly concentrated
and stable form to points of use where the lipid can be
admixed uniformly in any desired proportion with
virtually any type of animal feed product, or where it
can be incorporated in otherwise conventional
pelletized feed rations containing grain or the like,
or where it can be fed to animals by itself, all so as
to meet the nutritive requirements of the particular
animals in question. Indeed, except for the
encapsulated protein/lipid/aldehyde disclosures in
1'~778~4
Scott et al, U.S. Pat. No. 3,925,560 and Rawlings et
al, ~.S. Pat. No. 4,042,718, neither of which is
suitable nor approved for use as an animal feed
supplement because the aldehydes employed therein are
known carcinogens, none of the prior art approaches
have dealt specifically with the need to develop a
highly concentrated, integral, solid, dry, lipid and/or
lipid enrobed pellet or particle per se, enabling
lipids to be delivered to a point of use in stable, dry
form on a cost-effective basis. Thuæ, despite all of
the foregoing efforts, the ~state-of-the-art~ as it
existed at the time the aforesaid Related Application
wa~ filed is perhaps best described in the DIRECTOR'S
DIGEST, a publication issued by J. D. Schroder,
Technical Director, for the Fats And Proteins Research
Foundation, Inc. (~FPRFn) in Des Plaines, Illinois, the
September 1982 issue, No. 152, wherein it i8 stated:
"... m us far, there have been no breakthroughs in
the development of a low-cost, dry fat product. We
have followed up on the work that Dr. Boehme did in
identifying suitable carriers and have obtained cost
figures which will be helpful in considering a
product or product~ to manufacture.
~The number of suitable carrieræ for fat is quite
limited since absorbability characteristics are not
the same as for water-based materials such as
molasses. To complicate the situation, some
products may be suitable for certain markets, while
unsuitable for other markets.
1~778~4
-15-
"The potential fat carriers, which we have worked
with or are familiar with, can be classified as
either nutritional or non-nutritional. They are
listed below in terms of fat-carrying capacity,
s price and applicable markets.
FAT
F. O. B. CARRYING
"~C~ PRICE/CWT. $ ~E~ MARKET
~
Puffed rice or
wheat $50.00 75-80%All Species
Wheat middlings 4.5030-35% All Specie~ ex-
cept broilers
PAT
F.O.B.CARRYING
~IN~eDIENT ~RICE/CWT. $ CAPACIT~ ~B~E~
~Lt~G~7b31
Wheat Bran 4.5040% Cattle ~ Sows
Beet Pulp 6.5030-40% Cattle
Alfalfa Meal$4.00-7.5030% (est.) All Species ex-
cept broilers
~Non-Nutritional
Verxite
(expanded mica) $21.0070% Cattle
Corn-cob flour 5.50 50% Cattle &
perhaps swine
Bentonite 2.50 20~ Cattle.... n
1~77864
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The foregoing FPRF publication goes on to
point out many of the disadvantage~ in terms of
transportation costs, low fat content, excessively high
costs for higher fat content carriers, and
species-specific applicationæ for their use. Thus,
despite all of the efforts and expenditures in time and
money during the past two decades or more, the
"state-of-the-art~ in November of 19~3 for delivery of
lipid food supplements for animals contemplated the
impregnation of a host carrier that may or may not have
nutritional value and which significantly contributed
to the bulk, weight and delivery costs of the feed.
And, at the same time, problems of rancidity and
difficulty in handling persisted.
Faced with the fcregoing long-standing
problems and the unæucceæsful effortæ of reæearchers to
solve the æame, the inventor/applicant herein developed
improved lipid pelletization methods, apparatus and
products aæ disclosed and claimed in the aforesaid
Related Application. More specifically, and as
disclosed therein, solid lipid pellets containing 65%
to 95%, or higher, lipid concentrations suitable for
uæe in or aæ animal food supplements and/or feed
rations were provided wherein: a mixture containing at
least water and an edible algin/like coagulant ifi
formed in a mixing chamber; a liquified lipid i8 added
to form a gel-like lipid/coagulant/water emulæion; and,
the emulsion iæ depoæited in diæcrete quantitier into a
metal ion bath causing the emulsion to "set~ in a lipid
3~ pellet integral and solid throughout its entire
ætructure. The lipid pellets may be packaged for
delivery to pointæ of consumption and/or ad~ixed with
1,~77864
other feed materials to form nutritive animal feed
rations. Small amounts of ammonia and/or bentonite may
be added to the aqueous mixture to increase the lipid
absorptive capacity thereof. Various exemplary systems
are described in such Related Application for forming
such solid, integral lipid pellets.
SUMMARY OF T~E INVENTION
The present invention differs from that
disclosed in the aforesaid Related Application in that
the gel-like lipid/coagulant/water emulsion, rather
than heing ~set" in the form of integral, generally
homogeneous, lipid pellets either before or after
admixture with the ingredients comprising the dry
animal feed ration, is used to coat the outer surface
of conventional, commercially available, ~dry~ animal
feedstuffs and/or feed pellets and to thus form a
"dryn, stable, bound lipid/coagulant film or coating
encapsulating or enrobing the dry animal feed ration
wherein some proportion of the lipid may migrate into
the structure of the dry feed ingredients and/or
pellets and wherein the quantity of lipid added to the
dry feed ration may vary from a few percent lipids by
weight to virtually any desired percentage by weight,
commonly including percentages by weight ranging up to
on the order of 20% or 25% lipids by weight, or more.
In one of its preferred forms, the invention
contemplates the preheating of the conventional,
commercially available, dry, animal feed rations so as
to reduce the water of hydration level thereof below
the normal equili~rium level--which is generally in the
1~77864
-18-
range of from 10% to 13% water of hydration--prior
to application of the lipid/coagulant/water
emulsion. As a consequence of this arrangement, as
the emulsion "sets", the water content thereof and
5 the water content of the dry animal feed ration tend
to equilibrate, thereby rendering the product "self-
drying". Indeed, the moisture level of the
superheated, dry animal feed ration and the
percentage water by weight in the emulsion may, in
10 some instances, be selected such that the total
moisture content of the composite product will
equilibrate in the range between 10~ and 13% water
by weight--i.e., at or about the normal water of
hydration level for the composite product. In these
15 instances, no further drying is required or
desirable. In other instances where the moisture
content of the finished composite pellets exceeds
13%, the pellets may be subjected to further drying
if desired.
According to one aspect of the invention,
there is disclosed the method of synthesizing a
concentrated dry, lipid enriched composite feed
product comprising the steps of:
a) forming a lipid/coagulant/water emulsion
25 containing from about 0.25 to about 7.0% by weight
of an algin-like coagulant and from about 35 to 75%
by weight lipid, said emulsion being formed by
dissolving said coagulant in water and dispersing
said lipid therein:
b) applying the lipid/coagulant/water
emulsion formed in step (a) to external surfaces of
the food product; and
~ .'.
1~7'78~i4
--19--
c) so setting the lipid/coagulant/water
emulsion as to bind the lipid and coagulant
constituents thereof into a stable, essentially dry,
edible, bound lipid/coagulant coating on the food
products; and
d) the lipid comprising at least about
seven percent by weiqht of the total weight of the
food product.
Another, and more detailed, object of the
invention is the provision of a method of the
foregoing character wherein the "dry" animal feed
materials may optionally be preheated either prior
to or subsequent to pelletization so as to reduce
their moisture content to a level below the normal
water of hydration level thereof, thus enabling the
superdried particles or pellets formed to
equilibrate with the moisture content of the
lipid/coagulant/water emulsion so as to render the
composite lipid/feed rations essentially "self-
drying. In this connection, it is an object of theinvention to provide a lipid enrobement procedure
for dry animal fèed pellets which also takes
advantage of the heat generated in the pellets
during a conventional pelletizing process to assist
in drying the resultant product.
Yet another of the important objectives of
the invention is to provide lipid enrobed animal feed
rations in particulate and/or pelletized form which are
1~77864
--20--
essentially temperature insensitive and where the bound
lipid/coagulant ingredients will not exude liquid lipid
when subjected to pressure and/or elevated temperatures
as commonly encountered during times of storage and/or
transportation.
DESCRIPTIO~ OF THE DRAWING
The6e and other objects and advantages of the
present invention will become more readily apparent
upon reading the following detailed description and
upon reference to the attached drawing, in which:
FIGURE 1 i8 a highly diagrammatic, partially
block-and-line, flow diagram, here illustrating an
exemplary system for enrobing ~dry~ pelletized animal
feed product6 in a lipid/coagulant/water emulsion which
is thereafter "~et" 80 as to form an essentially ~dry~,
composite, lipid/feed pellet having an inner structure
defined by the ingredients of the dry feed pellets and
an outer coating of bound lipid/coagulant which is
essentially ~dry~, devoid of an oily surface, and
characterized by its lack of a propensity to exude
lipids, to agglomerate, and/or to become rancid and
spoil.
While the invention is susceptible of various
modifications and alternative fonms, specific
embodiment6 thereof have been shown by way of example
in the drawing and will herein be described in detail.
It should be understood, however, that it is not
intended to limit the invention to the particular form
disclosed but, on the contrary, the intention is to
cover all modifications, equivalents and alternatives
~778~i4
--21--
falling within the spirit and scope of the invention as
expressed in the appended claims.
1,~77864
DETAILEI) DESCRIPTION
En~-LLQnm~n~ of the Invention
Before turning to a description of the
features of the present invention, it may be well to
define what is meant by certain of the terms used
herein and in the appended claims. Thus:
The terms ~feedstuff~, "feed productn, and/or
~feed rationn, are herein used interchangeably to
connote any desired edible material having nutritive
value when fed to husbanded animals including: for
example, ruminants such as cattle, sheep, giraffes,
deer, camels and swine; zoo animals; horses; fowl;
canine or feline pets; fish; shrimp; birds; etc.; and
which may, merely by way of example, include such
materials as grains, alfalfa, corn and soymeal,
cottonseed meal, minerals, vitamins, and the like,
and/or mixtures thereof;
~he terms ~pelletsn, "pelletized~ and/or
~pelletizing~ are not intended to connote any
particular sized and/or shaped object; but, rather, are
used in their broadest sense to connote objects of
diverse sizes and/or shapes--e.g., pill-like, rod-like,
oblate, spherical, capsule-shaped, regular shaped,
irregular shaped, etc.--where the nutritive feed
ingredients have been compacted into discrete integral
forms, generally through the application of pressure
generating internal heat, by means of any suitable and
completely conventional and well-known extrusion-type
equipment, pellet mill or the like;
1~77864
-23-
The term "lipid" is used in its broadest
sense to include fats, oils ~other than essential
oils), and greases (other than hydrocarbon and/or
petroleum-based materials);
The term "algin-like coagulant~ is intended
to include extracts of seaweed such, for example, as
algin and/or ~holdfast" including not only
low-viscosity algins--e.g., an algin having a viscosity
on the order of about one hundred ~100) centipoise
(~cp~)-- but, also, high-viscosity algins having
viscosities up to on the order of one thousand (1000)
cp or more, as well as other materials having coagulant
properties capable of forming a gel-like emulsion when
mixed with water and lipids such, for example, as
extracts of okra or aloe vera, pectins, chitosan ~a
coagulant derived from the shells from shellfish such
as shrimp6, crabs or the like, or as formed on fungal
spore~ and the like). Thus, each of the foregoing
materials can be dissolved in a liquid; and, when so
dissolved, becomes calcium (or other suitable metal
ion) active in the same manner as algin, thereby
permitting cross-bonding of calcium (or other metal
ion) and algin (or other coagulant), generally 80 as to
render the coagulant--which theretofore had been water
2s soluble--water insoluble;
The term ~setting agent" is intended to
include metal compounds containing edible metals which,
when dis~olved in water, release metal ions that are
available to cross-bond with an algin-like coagulant,
generally so as to render the coagulant water
insoluble--and, may include various calcium compounds
such, merely by way of example, as calcium chloride,
,~778~i4
--24--
calcium bydroxide, calcium lactate, calcium phospbate,
calcium citrate, etc.; as well as compounds of other
edible metals such as iron, aluminum (which must be
used judiciously dependent upon the animal 6pecies to
5 be fed since, for example, some birds are sensitive to
aluminum content in their diet), or copper (whlch again
must be used judiciously since many animals are
sensitive to high concentrations of copper); and, in
the case of fish baits, borax which has been found
particularly advantageous since, while boron ions will
interact to ~setn the algin-like coagulant, the
coagulant will remain water soluble and, consequently,
the lipid/coagulant in or on the bait product will
function as a time-release agent, permitting the bait
to slowly dissolve as it is trailed through the water
so as to gradually release food particles and lipids
which serve as fish attractants; and,
The terms ~enrobement" and/or ~encapsulateD
are herein used interchangeably and are intended to
connote a lipid/pelletized or lipid/particulate dry
feed system wherein the pelletized or particulate dry
feed is preferably, but not necessarily, uniformly
coated over at least a substantial portion of its
external surface with a lipid/coagulant/water emulsion;
albeit that some portions of the eml~lsion are free to
migrate internally into the dry feed pellet or other
particulate dry feed ingredient.
Turning now to the drawing, and having in
mind the intended meanings of the foregoing terms as
used herein, there has been illustrated in FIG. 1 an
exemplary pelletized dry feed lipid enrobement system,
generally indicated in highly simplified diagrammatic
~ ,~778~;4
form at 10, embodying features of the present
invention. As here shown, "dry~ feed ingredients (not
shown) are delivered either directly to a conventional
pellet mill 11 as indicated by the solid line feed path
indicated at 12 or, optionally, via the broken line
feed path indicated at 14 through an oven or other
suitable and conventional heat source 15 and, from
there, to the pellet-forming e~uiement. AS the ensuing
description proceeds, those skilled in the art will
appreciate that the term "dry~ as here used means a
feed ingredient which inherently has a normal water of
hydration level ranging from about 10% moisture by
weight to about 13% moisture by weight. The pellet
mill 11 is, as indicated above, completely conventional
and forms no part of the present invention since the
particular equipment employed to form the compacted dry
feed pellets may vary widely from any conventional,
commercially available, pellet mill to extrusion
equipment (including spaghetti-type extruders or the
like), molds, etc.
Moreover, as the ensuing description
proceeds, those skilled in the art will appreciate that
the lipid enrobement process of the preæent invention
will find advantageous use in processing preformed and
prepackaged animal feed pellets formed at an entirely
different site and in a completely independent
operation. Nevertheless, in those ca~es where the
pellets are enrobed with lipids as a part or adjunct of
the pelletizing process per se, pellet mills 11 and/or
extrusion equipment have been found to be particularly
acceptable since they generally form compacted,
relatively dense, feed pellets by the application of
1~77864
--26--
pressure, a technique which inherently generates heat
in the pellet-forming process; and, as indicated in
greater detail below, advantage can be taken of that
inherently generated heat to promote uniformity of
5 lipid coatings and to assist in drying the coated
pellets. In the exemplary system 10 depicted in
FIG. 1, the pellet mill 11 serveæ to discharge discrete
compacted feed pellets, generally indicated at 16,
which are here shown as being gravity discharged to the
10 surface of a conventional conveyor belt 18.
In the exemplary form of the invention
depicted in FIG. 1, and in accordance with the
important aspects of the present invention, the
individual discrete feed pellets 16 are externally
15 coated with any suitable and desirable
lipid/coagulant/water emulsion. While such coatin~ may
be applied in a variety of ways--for example, in a
batch process by dipping the pellets 16 in a
lipid/coagulant/water emulsion contained within a
20 suitable dip tank (not shown)--the illustrative form of
the invention here depicted contemplates the use of a
spray application system, generally indicated at 19,
wherein the emulsion is formed and maintained in a
suitable mixing chamber 20, and metered quantities
25 thereof are withdrawn by means of a pump 21 and sprayed
upon the deæcending pellets 16 by means of one or more
spray nozzles 22. If desired, the æpray nozzleæ 22 may
be oriented to be contra-acting a~ shown and/or they
may be rotated about, or moved relative to, the falling
30 pellets so as to maximize the uniformity of application
of the emulsion to the external surfaces of the
descending pellets.
~77864
-27-
To promote uniform application of the
lipid/coagulant/water emulsion to the pellets 16 and to
enhance drying thereof while preventing agglomeration
of the thus coated pellets, the conveyor belt 18 may
5 typically take the form of a conventional vibratory
conveyor belt which serves to insure that the pellets
deposited thereon are in constant motion. Similarly,
conventional vibratory conveyors other than belt-type
conveyors may also be employed. ~oreover, such
continual pellet motion may be further promoted by
providing air agitation wherein cool or ambient air is
continuously blown up through the upper conveyor flight
18' by means of a perforate air distribution chamber or
agitator, here depicted at 24. Thus, the arrangement
lS i5 such that the moving pellets 16 are exposed to, and
coated by, the lipid/coagulant/water emulsion
distributed from spray nozzles 22, while the heat
inherently created in the pellets 16 during the
compaction process in the pellet mill, extruder, or
20 gimilar e~uipment, together with the continuously
flowing airstreams distributed through the mass of
vibrating pellets by the air agitator 24, serve to
enhance uniform surface coating of the pellets.
In carrying out the invention, provision is
25 made for "setting" the lipid/coagulant/water emulæion
film ormed on the pellets 16 so as to stabilize the
lipid and to provide discrete lipid enrobed or
encap~ulated pellets which are characterized by a
- ~dry", non-oily, external, bound lipid/coagulant shell
30 devoid of the propensity to weep or bleed lipid
exudates. To this end, an aqueous metal ion
solution--for example, a calcium chloride (CaC12)
1'~77864
-28-
solution--maintained within a tank 25 is withdrawn
therefrom by any suitable pump 26 and sprayed on the
continuously moving, vibrating, emulsion coated
pellets 16 by means of one or more suitable spray heads
5 or nozzles 28. Thus, the arrangement is such that
coaction of the vibratory conveyor 18 and air
agitator 24 serves to maintain the
lipid/coagulant/water emul~ion coated pellets 16 in
constant motion as they traverse the metal ion spray
10 application station defined by nozzles 28, thus
insuring that the pellets are uniformly coated with the
aqueous setting solution which serves to release metal
ions that react with the coagulant in the
lipid/coagulant/water emulsion to ~set~ the lipid in a
15 relatively firm, ~dry~, shell-like configuration
enrobing and/or encapsulating the discrete dry feed
pellets 16. That i8, the metal ion/coagulant reaction
serves to cross-bond the metal (for example, calcium in
a calcium chloride solution) and coagulant (e.g.,
~0 algin), rendering the coagulant--which theretofore had
been water soluble--water insoluble (except when using
borax to form water soluble lipid enrobed bait products
where the bound lipid/coagulant remains water soluble),
thus binding the lipid and coagulant so as to stabilize
25 the lipid in an essentially dry state devoid of the
propensity to weep, bleed or otherwise exude lipids in
the form of liquid exudates.
Those skilled in the art will appreciate that
the ~peed of the foregoing cross-bonding reaction
30 between metal ions and coagulant will, in large
measure, be dependent upon the concentration of metal
ion~ in the aqueous solution maintained within
1,~77864
-29-
tank 25. Experience has indicated that when using, for
example, calcium chloride, an aqueous calcium chloride
solution containing aæ little as 0.1% calcium by weight
will generally suffice to "set~ the
5 lipid/coagulant/water emulsion in a matter of a few
minutes, or even seconds, whereas stronger
solutions--e.g., 10~, 15~, 20~, 25~, or more--will
serve to "set" the emulsion virtually instantaneously.
At this point in the process, although the
lipid/coagulant constituents are bonded together, the
pellets 16 generally exhibit a wet external appearance,
principally as a result of the excess water content
within the aqueous calcium chloride (CaC12) or other
metal ion solution. Accordingly, in the practice of
the inve~tion, the discrete lipid enrobed pellets 16
are preferably conveyed on the vibratory conveyor 18,
which maintains them in confitant motion relative to one
another, and are passed over or through a further
drying station which may take the form of an oven (not
shown) or, a~ here depicted, the pellets may be
conveyed in heat exchange relation with a warm air
dryer 29 which serves to direct a multiplicity of
stream6 of warm air through the moving bed of pellets.
Upon completion of the drying cycle, the pellets 16 may
be discharged into suitable storage bins or the like
(not shown) or, alternatively, they may be transferred
to a further conveyor 30 for transport to suitable
automatic, semi-automatic and/or manual packaging or
bagging stations (not shown).
In the exemplary form of the invention
depicted in FIG. 1 and herein de6cribed above, the
pellets 16 are sprayed with the lipid/coagulant/water
~,~77864
--30--
emulsion as they are gravity discharged from the pellet
miil 11 towards the conveyor 18; but, those skilled in
the art will appreciate that the invention is not
limited to this exemplary arrangement. Thus, the
5 pellets 16 can be alternatively and/or additionally
sprayed with the emulsion after deposit on the conveyor
18. And, in some types of conventional pellet mills,
it i6 possible to spray the pellets after they have
been formed but prior to discharge from the mill.
Indeed, in its broadest aspects, the
invention permits spraying or other coating of the dry
feed ingredients per se prior to pelletization. Thus,
it i8 within the scope of the invention: i) to spray
or otherwise coat the dry feedstuff particles being fed
15 to the pellet mill 11 via feed path 12 (or feed path 14
after transit through heater 15) with the emulsion,
preferably while agitating the feedstuff particles;
ii) to spray or otherwise coat the emulsion coated
feedstuff particles with an aqueous setting agent such
20 as a calcium chloride solution; and iii), to then
introduce the thus lipid enrobed feedstuff particles
into the pellet mill 11 (or other suitable pellet
forming e~uipment) so as to compact the particles into
relatively dense pelletized form wherein the particles
25 of feedstuff within the pellets are lipid enrobed as
contrasted with the system shown by way of example in
FIG. 1 wherein the pellets 16 are lipid enrobed. And,
of cour~e, in those instances where the invention is
employed to lipid enrobe the feedstuff particles
30 per se, the lipid enrobed particles can be bagged and
distributed without pelletization since the lipid
exists in dry, stable, temperature insensitive form,
1~77864
-31-
bound by the coagulant, and, therefore, can be handled
with ease witbout risk of agglomeration and without
risk of rancidity.
One of the principal advantages of the
5 present invention resides in the ease and flexibility
of the proce~s which is essentially devoid of expensive
capital equipment requirements. Thus, in order to
implement a continuous processing line, there is
relatively little additional equipment required other
10 than a few ~pray nozzles for the emulsion and calcium
chloride application stations, together with some means
for agitating the enrobed feedstuff particles and/or
pellets to enhance uniformity of lipid application and
to prevent agglomeration of the enrobed particles or
15 pellets prior to "setting~ of the lipid/coagulant
coating. The enrobed particles or pellets output from
the system may be carefully controlled to produce
animal feed rations meeting virtually any lipid dietary
reguirement for husbanded animals and the like, ranging
20 from a few percent lipids by weight to 20%, or more,
lipids by weight. For example, in a continuous
enrobing process where ~X~ pounds of "dry~ particles or
pellets are to be lipid enrobed per unit of time to
form feed rations having 10% lipids by weight, the
25 exemplary system 10 depicted in FIG. 1 would be set so
that the lipid content of the lipid/coagulant/water
emulsion in tank 20 and the lipid spray application
system 19 are adjusted such that 0.1X pounds of lipid
are applied to the particle~ or pellets per unit period
30 of time. On the other hand, if the particles or
pellets are to include 15% lipids by weight, such
result would require only that one or more of the
1.,~7~864
--32--
operating speed of the conveyor belt 18, the lipid
content in the emulsion, and/or the quantity of lipid
sprayed per unit of time be adjusted so that .15X
pounds of lipid are applied to X pounds of dry feed
particles or pellets per unit of time. m ereafter, the
lipid enrobed particles or pellets produced may be
sorted and packaged for distribution to consumers in
accordance with the quantity of lipid included in the
finished pelletized or particulate feed ration.
Moreover, those skilled in the art will
appreciate that it is within the scope of the invention
to adjust the process parameter6 such that little, and
in some instances, no additional energy requirements
are needed to effectively dry the lipid enrobed
particles or pellets to a level of from only 10% to 13%
moisture content--i.e., to a level substantially in
equilibrium with the water of hydration level for the
dry feedstuff. For example, if the producer wishe6 to
form discrete, dry feed particles or pellets having 10
lipids by weight, from mixed grain and alfalfa or like
nutritive feedstuffs and, assuming that the
lipid/coagulant/water emulsion contains approximately
66% lipid by weight, 33~ water, and 1~ coagulant, then
it would simply be necessary to preheat the dry feed
ingredients in a heater 15, either prior to, during, or
æ ter pelletization, so as to reduce the water of
hydration level below its normal equilibrium point to
about 8~; and, to then add 15~ emulsion by weight to
85% Rdry" feed ingredients by weight. Thus:
85% dry ingredients at 8% moisture content
emulsion at 33% moisture content
100~; and,
~ ~778~i4
-33-
the resulting rations will comprise approximately: 10%
lipids by weight; 78% dry material by weight; and, 12%
total moisture. That is, the 8% moisture content of
the dry feed ingredients, when added to the 33% moisture
content of the emulsion, will tend to equilibriate to
form lipid enrobed rations having total moisture of
about 12%.
Similarly, if one wished to produce a lipid
enrobed particle or pellet having 15% lipids by weight,
the same dry feed ingredients might be preheated to
reduce the water of hydration level to 6%; and, the
emulsion applied as follow:
77.5% dry ingredients at 6% moisture content
+22.5% emulsion at 33% moisture content
100% and,
the resulting ration would contain approximately:
15.1% lipids by weight; 72.9~ dry material by weight
and, 12% moisture by weight.
As previously indicated, various types of
coagulent can be employed, of which the ones most
familiar to persons skilled in the art are algin. It
has been found that virtually any algin, irrespective
of viscosity and/or purity, will work well; but, where
one desires to employ a spray application system for
the lipid emulsion such as that indicated at 19 in
FIG. 1, products that have proven particularly excellent
include: Kelco Gel LV ~Trademark) and Kelgin LV
(Trademark) refined light viscosity--e.g., approximately
100 cp--algins offered for sale by Kelco Division,
Merck & Co., Inc., Chicago, IL Scotone ITrademark),
a refined light viscosity algin offered for sale by
Scotia Marine Product,Ltd., Princeton, NJ; and,
Protatek BF120 (Trademark), a light to medium
~77864
--34--
viscosity unrefined algin commonly referred to as
"holdfastn, offered for sale by Multi-Rem Corp.,
Ridgefield, NJ.
Desired proportions for the ingredients in
5 the lipid/coagulant/water emulsion have been found to
fall within the following general ranges:
Water 25% - 65~;
Lipid 35% - 75~; and,
Coagulant 0.25% - 7.0~.
10 If necessary, a suitable emulsifier--for example,
ammonium hydroxide ~N~sO) available from numerous
sources such as VWR Scientific, Seattle, WA--may be
added to the mixture in any desired amount ranging up
to about 5% by weight of the overall mix so as to
15 assist in forming and maintaining the desired emulsion.
As to the setting agent--for example, the
calcium chloride (CaC12) solution maintained in
tank 25--such setting agent may comprise an aqueous
solution containing virtually any desired concentration
20 of calcium chloride ranging from 0.1% - 2~ calcium
chloride by weight to 25% - 30%, or more, calcium
chloride by weight with the balance comprising water.
However, in those instances where it is deemed
undesirable to spray or bathe the lipid enrobed
25 particles or pellets with a solution containing up to
on the order of 98~ - g9~ excess water, it has been
found acceptable to prepare hiyhly concentrated aqueous
solutions of calcium chloride--e.g., 50% calcium
chloride by weight, or more--solutions (or other
30 soluble metal compounds in a solution capable of
releasing metal ions of an edible metal) where there is
only enough water added to the calcium chloride to free
~77864
the calcium ions; and, to then dilute such highly
concentrated solution by the addition of a liquid
desiccant such as propylene glycol to form a ~setting~
bath comprising, for example, 98% - 99% propylene
glycol and 2% - 1% highly concentrated aqueous calcium
chloride solution. Such an arrangement is also
advantageous in that it not only minimizes the excess
water added to the system but, additionally, in those
instances where the lipid enrobed pellets have a total
moisture content in excess of the normal water of
hydration level--e.g., 10% to 13%--residence in the
concentrated aqueous calcium chloride/propylene glycol
bath serves to remove excess moisture in the formed
pellets by virtue of the fact that propylene glycol
constitutes a desiccan~. me propylene glycol can, in
this type of system, be recirculated, heated to remove
excess moisture withdrawn from the lipid enrobed
pellets, reconstituted by the addition of a highly
concentrated aqueous calcium chloride solution, and
recirculated through the pellet or particle lipid
enrobement system to bind the lipid and coagulant
constituents applied to subsequent batches of pellets.
ExAyoeLE I
In carrying out the present invention on a
laboratory basis 80 as to form discrete, dry, lipid
enrobed pelletized animal feed rations, a supply of
~Complete Hog Finishing Ration" of the type
commercially available from Western Farmers Brand Feed
supplied by Cenex Ag., Inc., Seattle, WA, was heated
for approximately 20 minutes at 20UF. in a preheating
oven until such time that a slight color change
denoting carmelization of the surface of the pellets
~ ~778~i4
was observed. Based upon measurement of the weight of
the pelletized Hog Finishing Ration before and after
heating, and knowing that the unheated ration contained
approximately from 10% to 12% moisture by weight, it
was determined that the heating process served to
decrease the moisture content of the pelletized feed
ration to a range of from about 6% to about 8%. For
completeness, it is noted that the foregoing Complete
~og Finishing Ration~ containæ a guaranteed analysis of
13% minimum protein, 2.5% minimum fat, and 7.5% minimum
fiber; and, contains the following ingredients: Grain
Products; Plant Protein Products; Processed Grain
By-Products; Forage Products; Animal Protein Pro & cts;
Roughage Products; Feeding Cane Molasses; Lignin
Sulfonate; Salt; Magnesium Oxide; Manganous Oxide;
Cobalt Carbonate; Copper Sulfate; Ferrous Sulfate; Zinc
Oxide; Potassium Iodide; Calcium Carbonate; Yitamin A
Acetate; De-activated Animal Sterol (Source Of
Vitamin B-3); di-alpha Tocopherol Acetate (Vitamin E);
Vitamin B-12 Supplement; Riboflavin Supplement; Niacin
Supplement; Calcium Pantothenate; Choline Chloride;
Menadlone Sodium Bisulfite Complex; Pyridoxine
Hydrochloride; Thiamine Mononitrate; Sodium Selenite
(Selenium); d-Biotin; and, Folic Acid.
A lipid/coagulant/water emulsion was prepared
as follow~: 240 grams of 4% acid fat product referred
to as "Yellow Grease~ was melted and maintained at a
temperature of 125F.; 2.2 grams of Relgin LV (low
viscosity) algin was mixed separately in a blender with
120 grams of warm tap water until completely dissolved;
and, the liquified Yellow Grease was added to the
algin/water mix to make a total of 362.2 grams of
~ ,~778G4
lipid/algin/water emulsion which, when thoroughly
mixed, was put into a vibratory actuated spray gun.
me preheated pelletized Hog Finishing Ration
having a moisture content in the range of approximately
696 to 8% was then removed frcm the oven; and, 1000
grams of the superheated pelletized feed ration were
placed in a shallow stainless steel tray. me pellets
were then alternately sprayed until their exposed
surfaces were wet, stirred, sprayed and stirred
repeatedly until all of the 362.2 grams of emulsion had
been applied to the 1000 grams of pellets. At this
point, the pellets were sprayed vith a 10% aqueous
calcium chloride solution while being continuously
~tirred until the pellets exhibited a relatively
uniform wet appearance. Following application of the
calcium chloride solution, the pellets were
continuously stirred while being air cooled by blowing
ambient air across the surface thereof until such time
as the pellets lost their wet appearance.
~he foregoing laboratory experiment resulted
in a batch of lipid enrobed pellets totaling 1,362.2
grams in weight--viz., 1,000 grams of superheated
pelletized feed rations at about 6% to 8% moisture
content, and 362.2 grams of fat/algin/water emulsion at
a moisture content of 33.1308%. Thus, the finished
lipid enrobed pellets comprised: Fat = 240 9. - 1362.2
9. z 17.6%; Dry Matter = ~920 9. of pellets at 8%
moisture or 940 9. of pellets at 6% moisture + 2.2 9.
of alginl - 1362.2 9. = 67.796 to 69.296; and, water =
180 9. (896 water of hydration remaining in pellets
after preheating) or 60 9. at 6% moisture + 120 g.] -
1362.2 9. s 14.7% to 13.2%. The pellets were then
,~778G4
--38--
subjected to further air drying using forced ambient
room air for a period of 2 hours; at whlch point the
weight of the lipid enrobed pellets was 1,312 gram~
indicating removal of approximately 50.2 grams of
s water. Such pellets were stable, comprising
approximately 18.3~ fat by weight, between 70.3~ and
71.8~ dry feed and algin by weight, and between 9.9%
and 11.4% moisture by weight--e.g., a total moisture
content generally within the normal or equilibrium
10 water of hydration range for such products.
The resulting lipid enrobed pellets produced
exhibited a normal appearance; were characterized by
their integeity; and, exhibited little or no breakage.
The pelletg were dry to the touch; did not possess an
15 oily or grea~y surface film were free-flowing; and,
did not tend to agglomerate. The pellets, together
with other lipid enrobed pellets produced in the same
fashion using a variety of different lipids--e.g.,
lards, a variety of oils, restaurant grease (spent
restaurant oils and fats)--were stored in bags and have
exhibited no visible change in appearance, no
unpleasant odor, no rancidity, no tendancy to exude
lipids or oils, and no spoilage of any kind although
some of the pellets have been stored for more than 2~
25 years--this despite the fact that certain of the lipid
enrobed pellets have been subjected to temperature
extremes ranging from 32F. to, in one instance,
storage for a month at temperatures ranging from 120F.
to 130~.
