CA1277864C - Lipid enrobed fodder rations and manufacture thereof - Google Patents

Abstract

LIPID ENROBED FODDER RATIONS
AND MANUFACTURE THEREOF

ABSTRACT OF THE DISCLOSURE
Lipid enrobed animal feed rations in the form of discrete feed particles or pellets (16) formed from nutritive feed ingredients and enrobed in a lipid/coagulant/water emulsion wherein the lipid enrobed rations are coated with an aqueous setting solution containing a source of metal ions to cross-bind the metal ions and coagulant, generally rendering the latter water insoluble and binding the lipid and coagulant in a stable, dry condition; and, where the resulting lipid enrobed ration comprises:
i) a dry core of nutritive feed ingredients; ii) an external coating of bound lipid/coagulant in dry, stable form comprising up to, or in excess of, 20% of the overall feed ration by weight; and iii), a total moisture content which can be readily reduced to a range of from about 10% to about 13% of the total weight of the feed ration--i.e., a total moisture content which is in substantial equilibrium with the normal water of hydration level for such feed rations.
The lipid enrobed particles produced are dry, stable, do not exude liquified lipids, are not prone to rancidity and/or spoilage, are free-flowing, and will not agglomerate. Processes are disclosed wherein a lipid/coagulant/water emulsion is sprayed onto the surfaces of the particles, followed by spraying of an aqueous setting solution, in either a batch or a continuous production line; and, wherein the product is dried by the application of heat which can be, at least in part, generated in the pellet compaction process and/or by preheating either the pellets or the dry feed ingredients therefore so as to render the lipid enrobed rations, at least in part, self-drying.

Description

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 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 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 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 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 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 "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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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~.

Claims (18)

1. The method of synthesizing a concentrated dry, lipid enriched composite feed product comprising the steps of:
a) forming a lipid/coagulant/water emulsion containing from about 0.25 to about 7.0% by weight of an algin-like coagulant and from about 35 to about 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 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 weight of the total weight of the food product.

2. The method as claimed in claim 1, wherein the food product is an animal feed ration composed of a plurality of discrete, dry, feed ration particles.

3. The method as claimed in claim 2, including the further step of pelletizing the lipid coated feed particles.

4. The method as claimed in claim 2 wherein the feed ration particles are feed ration pellets.

5. The method as claimed in claim 4, in which the feed ration pellets are formed by pelletizing dry nutritive feed ingredients.

6. The method as claimed in claim 4 or 5 wherein the feed pellets are suitable for use as fish baits and the lipid/coagulant/water emulsion is set by the application thereto of an aqueous solution containing borax in an amount which is effective to cross-bond the boron ions in the solution with the coagulant, thus binding the lipid and coagulant into a dry, stable, water soluble form and thereby permitting time release of feed particles and lipids as the feed ration is trailed through a fish containing, aqueous environment.

7. The method as claimed in any of the preceding claims 1, 2 or 3 wherein substantially all of the external food product surfaces are exposed to said lipid/coagulant/water emulsion.

8. The method as claimed in any of the preceding claims 1, 2 or 3 wherein the lipid/coagulant/water emulsion is set by applying thereof a setting agent comprising an aqueous metal ion solution, for instance calcium ions, in a range or about 0.1 to about 30% by weight of the solution so as to cross-bind the metal ions released in the solution with the coagulant, thereby rendering the coagulant water insoluble and binding the lipid and insoluble coagulant together in a dry, stable form.

9. The method as claimed in any of the preceding claims 1, 2 or 3 wherein the ingredients of the lipid/coagulant/water emulsion are present in the following percentages by weight:
a) lipid - 35% to 75%
b) coagulant - 0.25% to 7.0%, and c) water - balance, the water constituting not less than about 25 and not more than about 65% by weight of the emulsion.

10. The method as claimed in any of the preceding claims 1, 2 or 3 wherein the food product is heated prior to application of the emulsion and the heated ingredients serve to evaporate moisture in the emulsion so as to render the coated food product self-drying.

11. The method as claimed in any of the preceding claims 1, 2 or 3 wherein the food product is preheated to reduce the water of hydration level thereof below the equilibrium level by such an amount that the moisture content of the emulsion applied to the food product and that of the food product tend to equilibrate at or near the equilibrium level of the water of hydration for the coated food product.

12. The method as claimed in any of the preceding claims 1, 2 or 3 wherein the coated food product include lipids, dry food product, and total moisture in the following ranges:
a) a lipid content of the order of 20% lipids, or more, by weight:
b) dry food product in a range of from about 60% to about 85% by weight; and c) total moisture in the range of from about 10% to about 13% by weight.

13. A food product as it may be produced according to a method as claimed in preceding claim 1.

14. A food product as claimed in claim 13 which is an animal feed ration.

15. An animal feed ration as claimed in claim 13, for animals including ruminants such as cattle, sheep, giraffes, dear, camels and swine; zoo animals; horses; fowl; canine or feline pets; fish;
shrimp; birds; and the like comprising, in combination:
a) nutritional dry feed ingredients in the form of discrete, edible feed particles; and b) a dry, stable, edible, bound lipid/coagulant coating applied to said particles and at least partially enrobing same: said lipid/coagulant coating: i) containing sufficient lipid material that the lipid comprises at least about seven percent by weight of the total weight of the feed ration; and ii) being set by application of a setting agent comprising an aqueous metal ion solution, so as to comprise the ability to maintain said lipid in bound relation with said coagulant for prolonged periods of time at a wide range of temperature extremes without tending to exude liquified lipids, and in a state devoid of the propensity to rancidify.

16. An animal feed ration as claimed in claim 15, wherein said discrete, edible feed particles comprise feed pellets, and/or pelletized dry nutritive feed ingredients.

17. An animal feed ration as claimed in any of the preceding claims 14, 15, or 16 with a total moisture content in the range of from about 10% to about 13%.

18. An animal feed ration as claimed in any of the preceding claims 14, 15 or 16 wherein the ingredients of said feed ration comprise:
a) lipid material in a dry, stable bound form and comprising at least about seven percent of the total feed ration weight:
b) moisture in the range of from about 10%
to about 13% of the total feed ration weight; and c) bound coagulant on the order of from about 0.25% to about 7.0% of the total weight of the feed ration; and d) wherein the balance of said feed ration comprises dry nutritive feed ingredients.