Process for treating pork cuts with PSE pork and composition thereof

Pale, soft and exudative pork (PSE pork) is particulated, an aqueous suspension of the particulated pork is prepared, and the suspension is impregnated into a cut of normal pork.

BACKGROUND OF THE INVENTION 
The present invention relates to impregnation treatment of meat, 
particularly pork, and to impregnation of pork with an aqueous medium, 
such as a solution medium containing brine salt and/or a curing agent, 
with or without a solubilizing agent and/or a cure accelerator, and/or 
other food and food-acceptable substances, and in particular, the present 
invention relates to utilization of pale, soft and exudative pork. 
In view of changing consumer attitudes and preferences over the past 
thirty-some years, pork producers have bred and fed pigs to reduce fat 
content and increase lean meat yield. As reported by Wirth, in his article 
"The Technology of Processing Meat Not of Standard Quality", 
Fleischwirtsch, 66 (8), 1986, pp. 1255-60, the lean meat:fat ratio of pigs 
has been altered over the years from about 1:1 to about 2:1. However, as 
also reported by Wirth, increased yield of lean meat has been achieved at 
the expense of quality since, as is accepted in the art, a significant 
percentage of lean-bred pigs, when alive, react adversely to stress, 
including stress induced by pre-slaughter procedures, which produces 
effects deleterious to the post-mortem meat. In fact, as reported by 
Topel, et al., "Porcine Stress Syndrome", Mod. Vet. Proct. 49:40, 1968, 
the stress not only may affect the quality of the meat, but also may lead 
to sudden death. 
One result of porcine stress syndrome is a rapid post-mortem glycolysis 
reaction in muscle tissue which effects production and accumulation of 
lactic acid in the muscle tissue and which effects protein denaturation 
and cellular damage. Such pork is whitish, or pale, in color, and in an 
uncooked condition, it has a soft, dry and mushy texture. These 
characteristics have lent the meat to be characterized in the pork 
industry and in the art as pale, soft and exudative pork (hereinafter 
"PSE" pork). PSE pork has what is considered in the pork industry and 
characterized in the art as poor functionality, including poor 
water-binding/retention characteristics and poor cure-color 
characteristics. 
One objective indicium for identifying what is characterized in the pork 
industry and in the art as PSE pork is that in less than 1 hr post-mortem, 
a glycolysis reaction produces lactic acid which effects a significant 
drop in the pH of the meat. In general, within that time period, the pH of 
the meat drops to at least less than about 5.8, and generally, PSE pork 
will acquire a pH of about 5.3 to about 5.4 within about 3 hrs 
post-mortem. It is also not uncommon for PSE pork to acquire a pH of less 
than about 5.3 upon complete rigor mortis. In addition, PSE pork may be 
identified because of the denaturation of proteins, which include 
denaturation of creatine kinase and, in particular, myosin and actomyosin, 
the denaturation occurring particularly during the first hour post-mortem. 
(Cf., Penny, Protein denaturation and water-holding capacity in pork 
muscle, J.Fd. Technol. (1969) 4, 269-273). 
In comparison, post-mortem glycolysis in what is considered as "normal", 
and hence desirable, pork results in a pH drop which is much more gradual 
and thus, not particularly detrimental to proteins and to cellular 
structure, in that the pH drops only to about 5.9 to about 6 in about 1 hr 
to about 3 hrs post-mortem. Moreover, upon complete rigor mortis, i.e., 
within about 8 hrs to about 12 hrs, normal pork has a pH above about 5.3, 
and generally from about 5.4 to about 5.8 and more particularly about 5.5 
to about 5.8. 
Because the extent of protein denaturation and cellular damage 
post-slaughter are primary variables which affect the texture and meat 
fluid-/water binding/ holding/retention capacity (hereinafter solely 
"water-holding" capacity) of pork products, normal pork sets the standard 
for the water-holding capacity and texture which consumers have come to 
expect and prefer and which is therefore sought as a standard in the pork 
industry. That, therefore, likewise sets the standard of high-quality, 
high value use and hence, the price standard for the commodity. 
Also in comparison, a third classification of pork is known as dark, firm 
and dry pork (hereinafter "DFD" pork). DFD pork has physio-chemical 
characteristics which, on a linear scale, oppose those of PSE pork, e.g., 
dark versus light color and good versus poor water-holding capacity 
characteristics, these characteristics being a result of post-mortem pork 
experiencing even less glycolosis than does normal pork. Upon completion 
of rigor mortis, DFD pork has a pH of above 6 and generally from about 6.2 
to about 7. 
A further indicium of identifying PSE pork is the genetic make-up of the 
pig based upon determination of the character of its halothane genes. In 
general, about 80% of the pig population has two recessive halothane 
genes, and these pigs are not particularly susceptible to porcine stress 
syndrome. However, if these pigs are subjects of unusual pre-slaughter 
environmental activity, they may stress sufficiently such that, all or 
part of their post-mortem meat may exhibit PSE characteristics. 
On the other hand, approximately 1% of pigs have two dominant, i.e., 
homozygous, halothane genes, and about 100% of these pigs provide meat 
which is characterized post-mortem as PSE pork. In addition, about 15-20% 
of the pig population have heterozygous halothane genes, i.e., one 
dominant and one recessive gene, and when these pigs are subjected to the 
usual stress in conventional large-scale slaughtering processes, their 
meat, too, in general, will be characterized post-slaughter as PSE pork. 
Thus, in general, up to about 20%, if not more, of the pig population is 
particularly susceptible to the effects of porcine stress syndrome which 
contributes to production of pork characterized post-slaughter as PSE 
pork. Also, however, in general, although the meat of an entire individual 
pig may be identified post-slaughter as PSE pork, it is found, such as 
with pigs having recessive halothane genes, as referred to above, or with 
pigs having heterozygous halothane genes, that not all cuts of any 
particular pig necessarily will have PSE characteristics. 
Therefore, in commercial packing facilities, whereat, in general, 
post-mortem meat is butchered into loin, ham and bacon cuts, i.e., 
respectively, the part of the sides between the shoulder and pelvis 
(loin), the thigh, hind leg and buttocks (ham), and belly, and remainder 
of the back and sides (bacon), the characteristics of each cut may be 
evaluated separately. Thus, particular cuts of an individual pig may be 
identified as being PSE pork, although other cuts of the same pig may not, 
and these differing cuts generally are segregated during processing. In 
general, for any particular pig, the ham cut will be found to be most 
susceptible to development of PSE characteristics. 
Although it is known that PSE pork takes up sodium chloride and other salts 
well because of its low pH, brine-cured PSE pork cuts present problems 
because of their poor water-holding characteristics, which are not offset 
by water-holding properties effected somewhat by salts. Also because of 
their poor water-holding characteristics, cooking PSE pork cuts for sale 
or consumption results in undesirable fluid losses, and hence, yield 
losses, which further contribute to an undesirable texture and mouth-feel. 
Thus, PSE pork cuts have been considered unsuitable for providing cured or 
cooked, or cured and cooked, or fried and/or smoked products, because of 
fluid losses experienced during cooking, frying and/or smoking, since the 
meat acquires a soft, dry and pithy texture during such processing, which 
is in contradistinction to a mouth-feel and bite consumers have come to 
expect from a quality high-value meat. Moreover, because of lactic acid 
accumulation, PSE pork also may be perceived as having acidic, i.e., sour, 
notes which further may detract from organoleptic appeal. 
In addition, exudate/drip from PSE pork cuts when packaged, particularly if 
such have been impregnated with brine and/or curing solutions, also 
presents an unappealing appearance to consumers. Furthermore, the poor 
water-holding capacity of PSE pork cuts inhibit their usefulness in 
ready-to-eat, pre-cooked and chilled products and in sliced products. 
Usefulness of PSE pork is also inhibited significantly in other so-called 
convenience foods, such as microwaveable products precooked products which 
require significant industrial processing prior to shipment for wholesale 
or retail sale. 
PSE pork, therefore, generally is considered a less than preferable and 
low-value product, and when it is sold itself as a cut, it is marketed 
generally as a non-label or off-label product. Thus, to enhance its value 
and usefulness, it has been proposed that it may be possible to use PSE 
pork for products wherein fluid loss is not of concern or wherein fluid 
loss is intended, i.e., dehydrated meat products. It is also possible to 
particulate the product and mix and preferably, emulsify it with other 
particulated meat products or by-products and/or with fillers and 
extenders to make luncheon meat-type products, such as bologna-type 
products, wherein a soft texture is not undesirable. 
To address the problems posed by PSE pork, in addition to resting pigs 
prior to slaughter, which generally is not practical in a large-scale 
commercial setting, it has been proposed that the meat be rapidly chilled 
immediately after slaughter to inhibit the conversion of glycogen to 
lactic acid and substantially avoid protein denaturation. That, however, 
as will be appreciated, involves not only a large investment in equipment, 
but also would involve treating pork which is not subject to the PSE 
problems. Moreover, it is not necessarily desirable to so treat all meats, 
and procedures have not yet even been proposed to enable identification of 
PSE meat prior to or immediately after slaughter, which would be required 
if PSE/non-PSE portions of individual pigs are to be segregated 
immediately and subjected to a post-mortem treatment. 
A further proposal to address the problems, which is much more practical 
and applicable to treatment of all meat without discrimination, has been 
advanced by Knipe, etal., "Effects of Stress-Susceptibility of Hogs and 
Processing Treatments on the Quality of Pork Products", Proc. Int. 
Congress of Meat and Sci. and Tech. Vol. 2, p. 662, 1990, wherein studies 
demonstrated that a quality improvement was effected by injecting prerigor 
pork with a curing pickle brine containing sodium 
tripoly-hexametaphosphate. 
However, PSE pork, which constitutes a significant percentage of 
slaughtered pork products, has been considered a problematic product and 
caused significant monetary losses in the industry. Thus, further means to 
address and alleviate the problems long have been desired and sought 
together with, alternatively, means to obtain more economic value from PSE 
pork than is provided by the uses noted above. 
SUMMARY OF INVENTION 
The present invention provides a process for treating pork and provides a 
pork composition which enable, particularly in a commercial context and in 
comparison with prior PSE products, obtaining a high quality and 
particularly a premium, high-value use of PSE pork. The present invention 
also provides for extending pork products, i.e., increasing the weight of 
pork products, without employing non-meat additives, e.g., starches and 
other fillers and extenders, as are known in the art. Hence, a product 
which is extended "naturally" is provided, i.e., a product which does not 
contain non-meat fillers/extenders. 
In the context of this disclosure, PSE pork is considered as being pork 
which has the color and texture characteristics which are identified above 
and recognized throughout the pork industry. It is considered as being 
pork having a genetic make-up including at least one dominant halothane 
gene. In addition, PSE pork is considered as being pork which has 
experienced a pH drop to a pH of below about 5.8 within 1 hour 
post-mortem, and particularly to a pH of from about 5.3 to about 5.6 
within about 3 hours post-mortem, with the attendant protein denaturation 
noted above, and denaturation of creatine kinase and/or more particularly, 
denaturation of myosin and/or actomyosin are further identifying 
indicators. 
Further, the term PSE pork as used herein is intended to include pork 
having a genetic make-up including a dominant RN gene. Although, RN-gene 
pork does not exhibit, in general, the rapid first hour pH drop and extent 
of protein denaturation experienced by PSE pork, it does exhibit a low 
post-mortem/post-rigor pH which impairs its water-holding properties and 
hence, its functionality and usefulness. 
In the context of this invention, "normal" pork is that which has 
characteristics described in the BACKGROUND above and is that which is not 
characterized in and accepted in the industry and art as PSE or DFD pork. 
Thus, normal pork may be characterized by having a pH on the order of from 
about 5.4 to about 6.0 and generally about 5.4 to about 5.8 and more 
particular a pH of from about 5.5 to about 5.8. Further, the term normal 
pork, as meant herein, is not intended to exclude pork which has a 
heterogeneous halothane genetic make-up if such meat has not experienced a 
pH drop of below about 5.8 within about 1 hr of slaughter and/or if such 
pork has a post-rigor mortis pH of from above 5.4 to about 6.0. 
A process of the present invention is characterized in that a cut of normal 
pork is impregnated with an aqueous suspension of particulate PSE pork. 
A composition of the present invention is characterized in that a cut of 
normal pork contains particulated PSE pork impregnated therein. 
In the context of the present invention, the normal pork cut into which the 
PSE pork is impregnated is meant to be whole pieces of pork and is to be 
distinguished from masses of comminuted meats and/or otherwise 
particulated meats. A "cut" is intended to mean an entire loin, ham, or 
bacon of a pig and further sub-divided cuts thereof, and generally 
premium, high-value cuts will be trimmed. 
Also in the context of the present invention, the PSE pork which is 
employed is raw, as is the normal pork. 
The present invention is characterized further in that although the aqueous 
medium of the suspension could be water alone, such preferably is a brine 
medium, and as is conventional in the art, a brine medium is meant herein 
to be an aqueous medium which includes sodium chloride, although 
employment of potassium chloride or other substitutable food-acceptable 
salt is not precluded. 
Further, the aqueous medium or the brine may be a curing solution, as is 
known in the art, and therefore, the aqueous medium includes at least one 
curing agent, such as nitrite and/or nitrate salts, particularly the 
sodium salts thereof. In addition such curing solution mediums also 
preferably include at least one solubilizing agent, such as an alkaline 
phosphate salt, including in particular tripoly-hexametaphosphate, and/or 
a cure accelerator/antioxidant, such as ascorbic acid and/or its isomers 
and salts thereof, particularly sodium erythorbate. 
Further, in the context of the foregoing, the present invention also 
includes a composition of an aqueous suspension of particulated PSE pork 
wherein the aqueous suspension medium is water alone or a brine or a 
curing solution, including a brine curing solution. The present invention 
also includes a cured normal pork cut having particulate PSE pork and a 
brine or a curing solution, including a brine curing solution, impregnated 
therein. 
The process of the present invention is characterized further in that 
impregnation is effected by injecting the suspension into the normal pork. 
For best results, the injected meat is tumbled after injection to effect 
uniformity of suspension distribution, and preferably, the meat is 
subjected to a tumbling/resting/ tumbling sequence, as is known in the 
art. 
In addition, the invention is characterized further in that the impregnated 
pork is treated to prepare a "pre-cooked" composition, which is meant 
herein to include smoking procedures to prepare a smoked composition. In 
the context of the present invention, as used herein, pre-cooking is 
intended to include any cooking procedure, particularly cooking procedures 
carried out prior to retail or wholesale, and in particular, any heating 
procedure which subjects the product to conditions which are suitable for 
preserving or preparing the meat for consumption. In the context of the 
present invention, the heating need not be carried out such that the cut 
is cooked suitably for consumption and thus, such pre-cooking heating is 
intended to mean any heating sufficient to pasteurize or otherwise render 
the meat microbiologically stable for storage for subsequent sale or use, 
including a sous vide process, or otherwise to cook the food at least 
partially. 
Further, therefore, the present invention also includes a pasteurized or 
otherwise at least partially cooked PSE-impregnated pork composition. In 
particular, the present invention includes a process and the product 
obtained by employing a normal pork cut suitable for preparing 
Canadian-style bacon, as defined by the U.S. Department of Agriculture, 
impregnating it and processing it to obtain a Canadian-style bacon. 
DETAILED DESCRIPTION OF THE INVENTION 
In the context of the present invention, the term "aqueous suspension" is 
used in its conventional manner and thus, is intended to mean a 
non-colloidal dispersion of solid particles in an amount of water. 
The aqueous suspension is characterized and distinguished from what is 
known in the art as a meat emulsion in that the suspension of the present 
invention has a lesser solids content than do emulsions which are also 
known in the art as batters. For example, emulsions generally have a meat 
content in excess of 50% by weight and in general, in excess of at least 
75% by weight, based upon the weight of the emulsion. Emulsions, 
therefore, generally have a pasty-type consistency. The suspension 
employed in the present invention has a thinner consistency, and although 
suspensions of the present invention may have a PSE meat content of up to 
about 30% by weight based upon the weight of the suspension, in general, 
the suspensions may have a PSE meat content of up to about 25% by weight 
but preferably, only up to about 20% by weight and more preferably, from 
about 5% by weight to about 15% by weight, each weight being based upon a 
weight of the suspension and the weight of the meat including its fluid 
content. 
As will be appreciated, the maximum amount of PSE meat suspension 
impregnated in a normal cut will depend, of course, upon the character of 
the normal pork cut being treated, including, for example, the 
water-holding capacity of the normal pork, and such may range up to an 
amount of about 25% PSE meat by weight, including its fluid content, based 
upon the weight of the combined PSE/normal meat composition. Generally, 
however, it will be found that amounts of PSE meat on the order of from 
about 5% to about 15% by weight, based upon the weight of combined 
PSE/normal composition, may be incorporated readily into the normal pork. 
In the present invention, the PSE pork employed may include what are known 
in the industry as trimmings, but particularly for premium, high value 
products, the trimmings and some connective tissue may be removed prior to 
processing the PSE pork in accordance with the invention. The PSE pork 
employed is size-reduced to a particulate form which has a particle size 
which is suitable for being impregnated into the normal pork, and such may 
be effected by equipment known in the art and available commercially. 
Preferably, the PSE pork is particulated to have a particle size so that 
it is suitable for being injected into the normal pork by injection 
equipment known in the art and available commercially. 
Depending upon the size of the cut of the PSE pork being employed, 
chipping, grinding/comminution and flaking and bowl chopping equipment 
known in the art may be used for size-reduction. The PSE pork is 
size-reduced best in a frozen condition and under refrigerated conditions 
which, as one skilled in the art will appreciate, facilitates 
particulation efficiency and operates to reduce deleterious effects to the 
character of meat, and although not required, tempering procedures known 
in the art may be employed. Thus, in carrying out the size-reducing 
operation, procedures desirably are employed for cooling the equipment by 
circulation of refrigerant fluids in the size-reduction equipment and/or 
introducing cooled gaseous or liquid N.sub.2 to cool the pork and 
equipment, as are known in the art. In general, the PSE pork which is 
size-reduced should have a temperature of less than about 0.degree. C., 
and the PSE pork may have a temperature on the order of from about 
-25.degree. C. to about 0.degree. C., and preferably from about 
-20.degree. C. to about -4.degree. C., and more preferably from about - 
10.degree. C. to about -4.degree. C. 
The particulate PSE pork employed for preparing the suspension desirably 
has a powder-like character, and as will be appreciated in view of the 
discussion below, the fiber of the particles generally are fibrous in 
nature and generally will extend lengthwise. For example, the particles 
may extend for a length of up to about 5 mm, but preferably, the pork is 
size-reduced so that such fibers extend in length for only up to about 3 
mm, such as particularly, from about 1 mm to about 3 mm. The powder-like 
character desired is gained by size-reducing the pork so that these 
particles have, in general, a thickness on the order of from about 100 
.mu. to about 1000 .mu. and generally, on the order of from about 400 .mu. 
to about 800 .mu.. 
The particulate PSE pork may be obtained, for example, by size-reducing the 
PSE pork in two stages such as by first treating PSE cuts with a flaker 
device and then with a bowl chopper device, as are known in the art. One 
may employ a flaker device such as a BUTCHER BOY flaker, which may be 
obtained from Lasar Manufacturing Company (U.S.A.), or a HYDRAU-FLAKER 
flaker, which may be obtained from General Manufacturing Corporation 
(U.S.A.). As is known, the meat processed by such flaker machines will 
provide flake-like particles having dimensions generally ranging from 
about 2 mm to about 30 mm. The flakes then are further size-reduced with 
such as Kramer & Grebe GmbH cutter-mixer (Germany) and like bowl chopper 
devices known in the art and commercially available. 
Subsequent to the size-reduction steps above, the powder is added to the 
aqueous medium for suspension formation. The formation of the suspension 
is carried out under conditions so that the temperature of the pork and 
the mechanical action on the pork, in particular, are such that 
deleterious effects, particularly extraction of proteins by water and/or 
solubilization of proteins, are minimized and preferably, substantially 
avoided. For suspension formation, milling equipment known in the art may 
be employed. However, although employment of what is known in the art as 
emulsion mills generally is not preferred, such may be employed, if 
necessary, under conditions, particularly of temperature, which minimize 
and preferably, substantially avoid extraction and/or solubilizing of 
proteins. Preferably, prior to suspension formation, and to facilitate the 
same, the aqueous medium and powder are mechanically mixed such as by 
stirring to achieve uniformity of the aqueous medium and powder. 
Mill apparati which will be found to be effective to obtain a suspension 
which may be impregnated readily into normal pork include equipment 
manufactured by Cozzini, Inc. (U.S.A.), and in particular, Cozzini 
machines having the designations AR-701 and AR-901 are employed usefully. 
In addition, process conditions disclosed in Cozzini et al. U.S. Pat. No. 
4,960,599 may be employed, and such are incorporated herein by reference 
as if fully set forth. 
In addition to merely employing water or brine, aqueous media which may be 
employed to prepare the suspension include those conventionally employed 
in the brine, curing, smoking and/or cooking arts, and thus, such are 
prepared with a view to the end product sought to be produced. In 
particular, however, alkaline phosphates preferably are employed, 
particularly tripolyphosphate salts, since such tend to result in 
enhancing water-holding capacity of the composition of the invention. It 
also is preferred to employ a hexametaphosphate salt in an amount 
generally from about 5% to about 15% by weight based upon the total weight 
of phosphate salts employed, this salt being employed for its 
water-softening, solubilizing effect, as is known in the art. 
In carrying out suspension formation and any prior mixing, temperatures on 
the order of less than about 5.degree. C. and preferably below about 
0.degree. C. are employed, more preferably, temperatures in the order of 
from about -15.degree. C. to -5.degree. C. are employed. Thus, the aqueous 
medium, be it a brine, curing solution, or brine curing solution, may be 
made with ice addition, or the mixing of the aqueous medium and powder may 
be carried out in chilled equipment, such as heat-exchangers known in the 
art, to effect such temperatures. 
Although, if the PSE pork is finely enough particulated, one might tumble 
and/or use pressure or vacuum to effect impregnation, more practically, 
the suspension is impregnated into the normal pork by injection, the 
criterion of significance being that the needles have a conduit and outlet 
aperture(s) of sizes suitable for passing the particulate pork 
therethrough. Injection may be carried out multiple times to achieve any 
of various injection levels, as is known in the art. 
Any of various commercially available injection apparati may be employed 
and include such as BELAM injection apparati by Wolfking Danmark 
Corporation (Denmark) or injection apparati by Mepsco, Inc. (U.S.A). In 
general, injection needles having an internal diameter on the order of 
from about 2.5 mm to about 3.5 mm and an exit opening on the order of 
about 2 mm to about 3 mm will be found suitable, and injection pressures 
on the order of from about 1.5 to about 4 bar, and preferably from about 
2.7 bar to about 3.5 bar, may be employed. In addition, although the 
normal pork which is injected may have a temperature of up to about 
10.degree. C., preferably it has a temperature of less than about 
4.degree. C. and more preferably from about 2.degree. C. to about 
4.degree. C. 
As referred to above, after injection, it is preferred, as is common in the 
art, at least to tumble the impregnated cut and more preferably, to 
perform a tumbling and resting sequence, as is conventional in the art, 
again under refrigerated conditions on the order of from about -5.degree. 
C. to about 10.degree. C. and preferably from about 2.degree. C. to about 
4.degree. C. 
Subsequent to impregnation and dispersal of the suspension, the impregnated 
cuts may be placed in casings which are substantially fluid-, i.e., 
water-, impermeable, such as fibrous or plastic casings, as are known and 
used in the art for shaping and molding meat. As will be appreciated, the 
casings not only shape and mold a plurality of impregnated cuts, but also 
urge the fluids to be retained within the meat while it is being 
manipulated such as by cooking or curing and/or curing and cooking, as 
also is well-known in the art. However, encasing the impregnated cuts 
should not be deemed as a requirement for practice of the present 
invention. 
Whether or not placed in casings, pre-cooking of the impregnated meat may 
be carried out by any of known cooking methods, and since the invention is 
directed to pork products, the aqueous impregnation medium and heating 
methods for preservation/cooking methods may be any of those known in the 
art including procedures for smoking, such procedures including those 
generally discussed in Ashbrook, BUTCHERING, PROCESSING AND PRESERVATION 
OF MEAT, 1955, Van Nostrand Reinhold Company, NY, N.Y., and in Dubbs, et 
al., THE EASY ART OF SMOKING FOOD, 1977, Winchester Press, NY, N.Y. 
In addition, PSE pork treated in accordance with the Knipe article noted 
above, wherein pre-rigor PSE pork is treated with addition of sodium 
tripolyphosphate, may also be employed in the process of the present 
invention and be incorporated in a composition of the present invention, 
and the disclosure of that article is incorporated herein by reference as 
if fully set forth. 
Although, as also indicated above, it is desired to obtain an entirely 
"naturally" extended meat composition, other substances which are known in 
the art as gel-forming agents, also known as binders, and/or fillers, also 
known as extenders, may be employed in the suspension or also impregnated 
in the normal pork, such substances generally being considered as 
enhancing cooking yields, since they act as water-binders and/or as 
film-forming agents. Such substances include starches and like 
carbohydrate substances and also include milk proteins, particularly whey 
protein concentrates and/or isolates, and/or other meat coaguable proteins 
and protein-containing substances, including egg albumen and gelatin, and 
include also pectin and gums. However, such substances preferably are 
excluded, since these substances will detract from the advantages provided 
by the present invention, i.e., obtaining an impregnated pork which has 
organoleptic characteristics, particularly texture and mouth-feel, which 
are substantially equivalent with that of a normal pork cut which has been 
prepared in the same manner, e.g., such as curing, etc., but without PSE 
pork addition. 
As will be seen from the Examples below, in comparison with normal pork, it 
has been discovered that even though PSE pork has poor functionality, 
particularly because of its poor water-holding capacity, impregnation of 
normal pork with particulate PSE pork does not increase drip loss to an 
extent of significance and does not adversely affect cooking yields to an 
extent of significance, as compared with like normal pork prepared in the 
same manner but without PSE pork addition. 
Moreover, although it has been found that the PSE pork may have an effect 
upon color of the product somewhat, the pH of a PSE/normal pork 
composition of the present invention is substantially the same as that of 
normal pork similarly prepared but without PSE addition, and texture also 
is not affected adversely. Hence, it has been discovered that since the 
PSE pork does not adversely affect the quality and organoleptic 
characteristics of the normal pork, the value of this unfavored low-end 
product is enhanced substantially by being incorporated into a premium 
high-value normal pork. 
Thus, proceeding in accordance with the process of the present invention, 
which provides a composition of the invention, enables PSE pork, which 
would provide premium high-value cuts if not for its inherent character 
due to effects of such as porcine stress syndrome and/or its pH, to be 
used in a premium high-value context. This use with a premium high-value 
product, i.e., normal pork, is accomplished without loss of the premium, 
high-value character of the normal pork since the particulate PSE pork may 
be prepared so it retains significant fibrous character and thereby does 
not detract from the texture and mouthfeel of the normal pork, as do other 
known additives such as gel-forming agents and fillers and also fats. 
Thus, because of this, it is preferred that cuts of PSE pork are 
incorporated into like cuts of normal pork, i.e., loin to loin, etc., 
although such is not required.

EXAMPLES 
The following Examples are set forth to illustrate the present invention 
further, and as was specifically indicated in the foregoing disclosure, 
percentages are set forth by weight. 
EXAMPLE I 
Post-rigor pork loins which are suitable for preparing a Canadian-style 
bacon, but which have been identified as PSE pork and have a pH below 5.3, 
are selected and trimmed of fat and connective tissue. The loins are 
chilled at a temperature of about -20.degree. C. to freeze them. The 
frozen loins are size-reduced with a BUTCHER BOY flaker under chilled 
conditions, which provides flake-like particles, and then the flakes are 
size-reduced further with a Kramer & Grebe bowl cutter under chilled 
conditions, and a powder-like product having a temperature of about 
-6.degree. C. is obtained. 
A brine curing solution is prepared with water and ice having a water to 
ice ratio of about 2:1, and with sodium chloride, dextrose, sodium 
erythorbate and nitrite. Sodium tripolyphosphate and hexametaphosphate, in 
a ratio of about 9:1, also are included in the solution. The particulate 
PSE meat is added to the brine to obtain an admixture containing about 67% 
water, about 1.5% dextrose, about 0.1% erythorbate, about 0.04% nitrite, 
about 0.8% phosphates and the balance PSE meat. The curing brine solution 
and meat are kept chilled at about -6.5.degree. C. and mechanically 
stirred to obtain substantially uniform mixture. 
After stirring, the brine curing solution and PSE meat mixture is fed 
through a Cozzini AR-701 mill so that the mixture is treated at a 
temperature of about -6.5.degree. C., and the mixture is passed through 
the mill three times which results in providing a fine suspension. 
The suspension is maintained at a temperature of about -6.5.degree. C. and 
provided to a BELAM injection apparatus for injection in to normal pork 
loins. The needles having an internal diameter of 3 mm and a 2.5 mm exit 
hole. The normal pork loins have a temperature of about 2.degree. C. and 
are injected twice with the suspension under a pressure which varies from 
about 3 bar to about 3.2 bar to inject an amount of the suspension so that 
an injected composition having about 91% normal pork and about 9% PSE pork 
based upon the weights of the two meats is obtained. 
The injected loins are size-reduced by cutting to obtain pieces having 
dimensions of about 12 cm .times.12 cm .times.10 cm. The injected pieces 
are vacuum tumbled in INJECT STAR tumblers for about 4 hrs at a 
temperature of about 10.degree. C., the tumbled pieces are rested for 
about 16 hrs at about 4.degree. C. and then tumbled again for about 1 hr. 
The tumbled pieces then are stuffed into fibrous casings with a RISCO 
vacuum stuffer. 
The encased products are heated and smoked in a Mauer and Sohne oven for 
preparing Canadian-style bacon for a time to obtain an internal meat core 
temperature of about 68.degree. C. The pre-cooked, smoked products then 
are chilled at a temperature of about 2.degree. C. for about 24 hrs. The 
casing then is removed and the products are vacuum-packed. 
COMISON EXAMPLE 
A brine is prepared with the same components as noted in Example I above 
and injected into normal pork suitable for preparing a Canadian-style 
bacon. The brine curing solution is injected at a level of about 30% of 
the normal meat green (uninjected) weight so that the injected normal 
product has about the same amounts of salt, dextrose, erythorbate, 
nitrite, phosphates and water as the PSE-injected product of EXAMPLE I. 
The injected normal meat is size reduced by cutting it into pieces as in 
EXAMPLE I, and the size-reduced cuts are treated in the same manner as the 
PSE-injected size-reduced cuts of EXAMPLE I. 
pH analysis of the product of the normal loin and the EXAMPLE I PSE-added 
product showed that there is no difference of significance between the 
pH's of the products. 
As may be seen from the Table below, based upon weights taken before and 
after cooking, after chilling and after removing the casing ("peeling"), 
for determining processing yields, it is found that the incorporation of 
the PSE meat increased yields, although not to a degree of significance. 
TABLE I 
______________________________________ 
YIELDS 
Product Cooking(%) Chilling(%) Peeling(%) 
______________________________________ 
EXAMPLE I 92.60 91.04 90.10 
(91% Normal + 
9% PSE) 
100% Normal 91.55 89.78 88.71 
______________________________________ 
Drip loss determinations also are performed on vacuum-packed samples which 
have been stored for 21 days at about 4.degree. C. Based upon the weight 
of the product taken before cooking, it is found that although the EXAMPLE 
I product exuded less drip, the difference is not one of significance. 
Thus, even though PSE pork has poor water-holding or binding capacity, the 
PSE pork of EXAMPLE I does not adversely affect yield losses and drip. 
Analytical evaluations of color indicated that the Hunter L value of the 
EXAMPLE I and normal products differ to a degree of significance (EXAMPLE 
I--54.05; normal--59.07) with the EXAMPLE I product being darker which is 
surprising, since it would be expected to lighten the normal meat, but the 
Hunter a and b values do not differ between the products to a degree of 
significance. Analytical evaluations of texture also indicate that the 
EXAMPLE I and normal products do not differ to any degree of significance. 
As is clear from the foregoing, various modifications of the present 
invention may be made without departure from the spirit and scope of the 
disclosure, and the invention may be embodied suitably in the absence of 
elements, members, constituent composition components and/or process steps 
and/or parameters not specifically disclosed or excluded herein.