|
Ed note: this article first appeared in the February, 2000, Goat Rancher magazine. Reprinted with permission of the author.
Preface
Live animal and meat grading/classification systems facilitate the flow
of products through the constrictive link between the broad production base and
the diverse consumption base that collectively is known as the market. The
sorting and information filtering that occurs in the marketplace provides a
common language for determining price differentials and feedback from consumers
to producers. In general, marketing systems for red meats have evolved into
highly complex, organized distribution channels from producers to
slaughterers/processors to institutional firms and retail outlets. Such meats
are traded in sufficient quantities to require common terminology,
specifications, and standards for buying and selling carcasses, primal cuts, or
case-ready retail portions. These market communication and classification
systems are now commonplace with the notable exception of goats and goat meat.
Accordingly, the goal of the research reported below was to develop a similar, practical system for goats and goat meat.
Introduction
The USDA Agricultural Marketing Service Grading and Standardization
Branch has developed Institutional Meat Purchase Specifications (IMPS) for fresh
beef, lamb and mutton, veal and calf, pork and fresh venison. Additionally,
IMPS series for cured, cured and smoked, and full-cooked pork products; cured,
dried, smoked and fully-cooked beef products, variety meats and edible
by-products, and sausage products have been developed to fulfill the need for
standardized terminology and classification systems for these items. The
original IMPS were developed in the late 1950's by USDA in conjunction with
interested procurement agencies and suppliers. They replaced the National
Association of State Purchasing Officials (NASPO) specifications for meat
products. The IMPS are mandatory only when specifically included in procurement
contract provisions and are maintained as voluntary consensus specifications
that reflect both purchaser demand and products that industry can produce. The North American Meat Processors Association has published a color
directory of institutional cuts that are closely aligned with the IMPS cuts.
The IMPS standards facilitate communication within and between market
sectors by providing data to be specified by the purchaser, e.g., weight ranges
of carcasses and cuts, weight and thickness tolerances, cutting instructions,
special material requirements, and specific item descriptions. Development of
quality assurance provisions provide for product examination to determine
defects and quality acceptance of IMPS cuts.
A corollary result of our earlier research on branded goat meat
specifications (McMillin et al., 1997) was a preliminary investigation of IMPS
requirements and fabrication techniques for goat meat carcasses and cuts. Our
current research promotes the development and, hopefully, widespread adoption of
standardized market communication for goats and goat meat which could do much to
bring order and stability to current goat meat marketing channels (now
characterized as being poorly structured, lacking in standardized processing
techniques, and having inadequately developed product identification and
distribution (Pinkerton, 1995).
Commercial utilization of new IMPS standards for goat meat would require
a corollary scheme of live and carcass classification. Live standards that
accurately correlate with carcass traits and meat characteristics have been
successfully implemented for a few of the other livestock species, and
preliminary data (McMillin et al., 1997) have illustrated the feasibility of
developing such classifications for goats, at least for Spanish meat-type kids
over limited weight ranges. Evaluation of additional breed types, ages, weights
and body conformations typical of slaughter goat populations in the U.S. are
needed to more fully develop a useful classification scheme for live goats and
goat meat in marketing channels. Subsequent educational programs for those
market players that would gain from uniform classification systems would promote
the adoption of these systems in industry practice.
Research Objectives
The overall objective of this research was to develop sorting and
classification systems to facilitate live goat marketing and goat meat
purchasing in wholesale and retail channels. More specific research objectives
were to:
1) Sample a variety of Angora, Spanish, dairy and Boer-cross goats to
determine suitable live selection (classification) criteria for use in live goat
marketing channels.
2) Provide data on different IMPS item specifications and primal cuts from
goats of varying weights, sizes, and breed types to develop preliminary IMPS
guidelines.
3) Survey auction markets, goat traders, meat wholesalers, and
institutional goat meat purchasers to determine the prospective usefulness of
live goat classification criteria and goat meat IMPS in industry practice.
Research Procedures
Wether goats of four breed types (Angora, Spanish, dairy, and Boer X
Spanish-cross), three ages (kid, yearling, and adult) and visual conformation
scores (classification categories 1 through 3) were procured from several Texas
and Louisiana ranches and delivered to the Southern University abattoir, Baton
Rouge, LA in nine groups. Reflecting industry practices, 12 nannies were also
included in the adult group of dairy goats. The numbers in each category for
the 276 total goats are in Table 1.
Table 1. Numbers of goats in each age and breed category.
|
Age =>
|
Adult
|
Yearling
|
Kid
|
|
Angora
|
39
|
38
|
35
|
|
Boer-cross
|
0
|
11
|
47
|
|
Dairy
|
17
|
2
|
9
|
|
Spanish
|
10
|
28
|
40
|
After holding overnight (with water, but no feed), certain live linear
measures were taken on each goat: length of rump, loin, and chine; chest and
shoulder widths; chest depth; height at withers and at hip; barrel
circumference; and heart girth. Body conformation scores were assigned by
experienced livestock graders using declining gradations of prime, choice, good,
and cull. Thereafter, still slide photographs and videotapes were made of
individual goats to enable review when comparing live grades to carcass grades.
Live (shrunk) weights were taken just prior to slaughter by humane
procedures after which the hot carcasses were weighed and then chilled at 34?F
overnight. The next morning an experienced meat grader assigned scores for
carcass conformation using declining gradations of prime, choice, good, and
cull. Carcasses were also visually appraised for percentage of kidney and
pelvic channel fat, color of flank lean, and fat cover over the rib cage.
Objective color of lean in the flank and semimembranosus muscle on the outside
of the rear leg was determined with a portable reflectance colorimeter.
Photographs and videotapes of side and rear views of each carcass were made for
comparing carcass grades to live grades.
Dressing percentage was calculated as hot carcass weight divided by live
(shrunk) weight x 100%. Chilled carcass weights were recorded following cooling
overnight.
Results and Discussion
The population of goats chosen for the project were selected to be
representative of those entering the marketing and meat channels in the U.S.
Ages of goats were not precisely known and researchers relied on teeth count to
separate kids, yearlings, and adults. Of the goats selected for this study, the
Boer-cross kid goats were heavier (P<0.05) than the kid goats of the other three
breed types, Spanish and Boer-cross yearling goats were heavier (P<0.05) than
the Angora and dairy yearling goats, and the dairy adult goats were heavier
(P<0.05) than the Angora and Spanish adult goats.
Boer-cross kids were longer (P<0.05) through the rump, loin, and chine,
had wider (P<0.05) and deeper (P<0.05) chest dimensions, and had larger (P<0.05)
heart girth and barrel circumference measurements than kid goats of the other
breeds. Spanish yearling goats had slightly greater dimensions at each
location, including height at withers and height at hip (P<0.05), than
Boer-cross yearlings, which could indicate differences in maturation patterns
between the two breeds. Angora goats had smaller dimensions at each age
compared with goats of the other breeds. Yearling goats of each breed generally
had greater dimensions at each location than kid goats of the same breed and
adult goats correspondingly had greater dimensions than the yearling goats.
Spanish and Boer-cross kid and yearling goats had higher subjective live
conformation scores than Angora and dairy kid and yearling goats.
The live animal traits were generally highly (P<0.0001) correlated with
one another, indicating that animals that were larger in one measurement were
usually larger in another similar measurement. An exception was the live
conformation score. The subjective live conformation score was highly (P<0.005)
related to chest width and barrel circumference measurements, but not to other
linear or dimensional live animal traits. This suggests that the measurements
of several dimensional traits should be combined to result in an overall
conformational image of the live goat. Alternatively, it may be that the live
measurements that were chosen, based upon common measurements of dairy and
breeding goats, were not precise enough to define the differences in
conformation or shape of meat goats.
Based upon the body dimensions and live conformation scores, project
scientists then determined the parameters that were deemed to be important in
the sorting and marketing of live goats and thereafter devised four
classification groups. Selection classification group one included goats with
conformation scores of high choice and prime. Selection classification group
two included goats with conformation scores of average and low choice. The
third selection group contained goats with good conformation while the fourth
selection group contained goats with inferior conformation. The descriptions of
goats chosen in each selection classification group are in Table 2. (Pictures
of the representative goats in the selection classification groups are in the
Final Report to USDA-AMS and will be released following final approval and
adoption.) Additional classification criteria that are important in
distinguishing between market goats are age, sex class, and weight in addition to the conformation, muscling and shape that determine the selection
classification group. Some of the USDA Market News Reporters have adopted these
market goat category recommendations and are now reporting live goat prices
based upon age, selection group, weight, and sex. (See the Internet market
reports from the San Angelo, TX auction, Ms. Becky Sauder, reporter;
www.ams.usda.gov/lsg/mncs/ls_satx.htm)
Table 2. Descriptions for live classification group criteria of market goats.
| Selection | Goat description |
| 1 | Goats possessing minimum qualifications are moderately thickly muscled
throughout. The back and loin are moderately wide and shoulders and hips are
moderately neat and blend smoothly into the body. There is a slight fullness or
plumpness over the rib, loin, rump and legs that contributes to a somewhat
rounded and moderately refined appearance. |
| 2 | Goats possessing minimum qualifications are slightly thickly muscled throughout.
The back and loin are slightly wide with loin, rump, and leg almost flat with
little or no evidence of fullness. The hips and shoulders are somewhat smoothly
laid in, but appear slightly prominant and contribute to a slightly refined
appearance. |
| 3 | Goats possessing minimum qualifications are thinly muscled throughout. The
back, loin, and rump are narrow with a slightly sunken appearance. Legs are
tapering and narrow with hips and shoulders somewhat prominent. Goats usually
show either heavy bones and thin fleshing associated with coarseness or small
bones and angularity denoting over-refinement. |
Cull
Goats possessing cull qualifications are very thinly muscled throughout. The
back, loin, and rump show little indication of muscling and have moderate to
great shrunken appearance. Legs are very tapering and narrow with hips and
shoulders very prominent. Goats are often those culled for inadequate frame
size or body capacity or those with reproductive deficiencies.
Although we took exhaustive carcass measurements and examined many
relationships among them, we present below only those findings we feel to be of
relevance and interest to producers.
The hot carcass weights of the goats were closely related to the live
weights (r = 0.92). Boer-cross kid goats had heavier (P<0.05) hot carcass
weights than kid goats of the other three breeds and Spanish and Boer-cross
yearling goats had heavier (P<0.05) hot carcass weights than the Angora and
dairy yearling goats. The adult dairy goats had heavier (P<0.05) hot carcass
weights than Angora and Spanish adult goats because the live weight was much
heavier. There were only slight variations in dressing percentage or yield of
hot carcass between breeds. Dressing percentage was lowest for Angora kid goats
and tended to be lower for dairy goats of each age group when compared to goats
of the other three breeds for each respective age group. Average dressing
percentages across age groups were 48 to 54% for Spanish and Boer-cross goats
and 43 to 49% for Angora and dairy goats in this study. Cold carcass weight
followed similar trends to the live weight and hot carcass weight data. The simple correlation between hot and cold carcass weight was
very high (r = 0.96).
The carcass conformation scores (grades) were higher (P<0.05) for
Boer-cross kid goats than for kid goats of other breeds. Spanish and Boer-cross
yearling goats had higher (P<0.05) carcass conformation scores than Angora and
dairy yearling goats. The simple correlation between live conformation score
and carcass conformation score was 0.57 (P<0.01), which indicated a moderate to
high relationship between the subjective scores. (It was noticed that the
assigned live score became closer to the carcass score as the study progressed
(practice does make perfect, here as elsewhere).
The visually estimated kidney and pelvic fat percentage was higher
(P<0.05) in Boer-cross kid goat carcasses compared with the carcasses from other
breeds of goats. Spanish yearling goat carcasses had greater (P<0.05) amounts
of estimated kidney and pelvic fat than carcasses from yearling goats of the
other breeds. Carcasses of dairy adult goats had the greatest (P<0.05) amount
of estimated kidney and pelvic fat. The actual (weighed) percentage of kidney
and pelvic fat was similar to the estimated kidney and pelvic fat percentage,
the simple correlation being 0.82.
The subjective flank color score was lighter, indicating less maturity,
in carcasses from younger goats. Flank color in carcasses of Boer-cross kid
goats was darker (P<0.05) than the flank color in carcasses of goats from the
other breeds. The flank color of Angora yearling carcasses was similar to that
of carcasses from Boer-cross kid goats and much lighter (P<0.05) than the flank
color of carcasses from yearling goats of the other breeds.
The objective lightness color of leg and flank was decreased with
increased age of goats. Leg color was lighter (P<0.05) in carcasses from Angora
and dairy kid goats compared with carcasses from Boer-cross and Spanish kid
goats. Similar trends were observed for flank lightness values.
The color of lean is very important to some purchasers of goat meat, with
a lighter, pinker color being perceived to be associated with meat from younger
(and presumably more tender) goats. The current data with subjective flank
color and objective leg and flank lightness values would generally support the
concept of lean from younger animals being lighter in color, but the simple
correlations of subjective flank color with any of the objective colorimeter
measurements values were low, less than r = 0.40. The relationships between
lightness of flank and leg, redness of flank and leg, and blueness of flank and
leg as measured by the colorimeter were also low (r ? 0.50). Color is a very
complex measurement and no single color measurement on a carcass seemed to
precisely measure the color as perceived by a trained human evaluator.
The subjective external fat score increased with animal age of carcasses
from Angora, dairy, and Spanish goats. The Boer-cross kid goats had received
some grain and had slightly higher levels of external fat than the Boer-cross
yearling goats that were raised only on pasture. It was anticipated that
external fat would increase in goats of older ages as a normal indication of
increased animal maturity. The external fat score was correlated with estimated
kidney and pelvic fat (0.60) and actual kidney and pelvic fat (0.56). Readers
should be aware that growing/aging goats deposit fat first (and in the greatest
quantity) in the kidney/pelvic region and secondly over the rib cage. Only
rarely does a goat get enough extra feed to lay down fat along the top if its
back; similarly with marbling (the intramuscular deposition of fat). Other red
meat species are specifically fattened in feedlots to have excessive external
fat that is deposited somewhat uniformly along the back and over the ribs before marbling is deposited inside the muscle.
Carcass classification groups were developed based upon the relative
carcass conformation (appearance and shape). The descriptions for the carcass
classifications are in Table 3.
Table 3. Descriptions for carcass classification group criteria of market goats.
| Selection | Goat description |
| 1 | Carcasses have a superior meat type conformation and are thickly muscled
throughout the body. Rib, loin, rump, and legs show particular fullness of
muscling. Lean color is pale red to slightly pink. Fat cover score is 2 or |
| 2 | Carcasses have an average meat type conformation, with a moderate degree of
muscling throughout the body. Rib, loin, rump, and legs may be almost flat.
Lean color is pale to moderately red. External fat cover must not completely
cover the legs or shoulders, with a fat cover score of less than 3. |
| 3 | Carcasses have a meat type conformation, with a thin degree of muscling
throughout the body. Rib, loin, rump, and legs are narrow and may be slightly
sunken or hollow. Lean color is pale to moderately red.
|
Cull
Goats have a poor meat type conformation, with less than thin degree of muscling
throughout the body. Rib, loin, rump, and legs are very narrow and flat, with
definite signs of being sunken or hollow. Lean color is moderately red to very
dark red.
Mathematical correlations between live traits and carcass traits were
determined. Hot and cold carcass weights were each highly related to live
dimensional measurements, but not to live conformation score (grade). Indeed,
as indicated earlier, only two live goat measurements (chest width and barrel
circumference) were significantly correlated with subjective live goat
conformation grades. Worse still, we did not find any of the live measurements
to be closely related to carcass grade. However, we did find a rather close and
repeatable relationship between live conformation grade and carcass conformation
score (r = 0.57); both are, of course, subjective, not empirical.
In practical terms, this means that trained live goat graders (and
experienced commercial buyers) can predict with reasonable accuracy the
corresponding grade of the chilled carcass and, accordingly, estimate carcass
monetary worth and, by calculation, live price per pound to be paid. The phrase
"reasonable accuracy" is here purposely employed. Similarly, precise
descriptions of carcass quality characteristics are exceptionally hard to
devise. Indeed, author Pinkerton, speaking at a 1993 Boer goat symposium in
Canada, suggested that "assessing meat goat quality is rather like appraising
pornography- it is fairly easy to do, but it is pure hell to describe." His
position remains unchanged some thousands of goats and hundreds of carcasses
later.
To meet research objective two (develop preliminary IMPS guidelines),
carcasses were fabricated into prototype IMPS cuts, with feedback from AMS
personnel. These cuts were predicated upon preliminary cutting of carcasses
into primal and subprimal cuts weighing 2 to 5 pounds, with additional criteria
of cuts being easily made with a power saw or knife, cuts being made along
natural muscle seams or at easily determined carcass locations, and cuts looking
attractive with an optimal amount of lean mass per cut. After exploratory
efforts, five cutting styles were developed, based upon the relative carcass
weights. These styles and the weights (average and ranges) for the major cuts
in each style are shown in figure 1. Platter style goats have intact carcasses
weighing less than 15 pounds with only the trotters removed. Front legs are
folded into the tendinous joints of the hind legs before chilling. Roasting
style goat carcasses weigh 16 to 20 pounds and have large primal cuts suitable for roasting similarly to platter goats. Barbeque style goat
carcasses weigh 21 to 30 pounds and are characterized by removal of the fore arm
from the body and leaving the shoulder and rib area attached in a large piece.
The weight of Southern style goat carcasses is 31 to 40 pounds, with six major
cuts having generally larger weights than for the other carcass styles. Hotel
style carcasses weigh more than 40 pounds, with cuts designed to provide larger
portions for the hotel, restaurant, and institutional purchasers who will be
cutting smaller portions on demand for their patrons.
To achieve objective 3, we interviewed selected Texas goat producers and
various industry representatives to get their opinions and comments on our live
and carcass grading systems and on our suggested IMPS cutting styles and related
topics.
Most of the participants agreed that market news reporting services were
useful to them in goat selling or buying. A lesser number thought that more
market classifications would increase prices for goats and that the number of
market classifications in the market news reports had increased recently; they
credited our research findings, as applied by AMS market reporters and some of
their state counterparts. Most responses indicated that pictures or charts of
classification groups would be useful, that uniform evaluation criteria would
likely increase prices of goats, that uniform evaluation criteria would likely
increase sales of goat meat, that standardized cutting methods would facilitate
purchase and selling of goat meat, and that increased goat meat purchases by
restaurants and retail stores would likely increase goat prices. Fewer survey
respondents agreed that uniform carcass evaluation systems would promote
transport of carcasses instead of live goats.
Discussions with the producers indicated that other changes within the
goat industry are needed in addition to classification systems and IMPS cuts.
Assistance with production practices and more producer education programs were
desired. Producers were receptive to IMPS, feeling that the system could
improve institutional purchases of goat carcasses and meat over time. It was
felt that the classification systems for live goats and goat carcasses might
improve farm prices if the systems were widely adopted in the market channel.
Project personnel met with slaughter representatives in western Texas and
gained their opinions of the classification systems and IMPS cuts. A trip was
made to the NJ and PA areas near New York City to visit auction markets,
processors, and retailers of goat meat. No formal surveys were taken of the
individuals in Texas and New York City area because it was felt that informal
conversation would result in more accurate and detailed responses to inquiries
into their businesses. In general, the individuals in the middle of the
marketing chain of live goats to consumers were not receptive to any imposition
of live or carcass classification systems since the current marketing procedures
would appear to be skewed to their advantage from supply and price perspectives.
Processors and wholesalers to retailers in ethnic-oriented markets were
noncommittal or only slightly interested in use of IMPS in current marketing of
goat meat. A prevailing opinion was that retail stores wanted to purchase whole carcasses rather than cuts because their ethnic
customers wanted to see the carcasses being made into cuts. Some processors
conceded that IMPS would likely have utility for competitive bidding purposes by
institutional purchasing agents. Processors in Texas and the NYC area generally
thought that there was no lack of slaughter capacity, that the site of
production does highly influence the location of slaughter facilities, that the
hotel trade currently is for lighter weight carcasses (under 40 lb.), and that a
grading system might aid in selling of goats and goat meat. The NYC processors
indicated that there was concern with the quality and price of imported goat
carcasses compared with domestic goat carcasses.
Summary and Conclusions
Our research resulted in live and carcass classification systems,
provided data for preliminary IMPS goat meat cuts, and elicited insights from
industry personnel on the usefulness and changes needed in the systems. Goats
sampled from Texas and Louisiana farms and ranches were representative of those
currently being marketed and provided sufficient variation to allow development
of preliminary live goat and carcass classification systems. The elements of
the live goat system were deemed successful because the general system is now
being implemented for price reporting purposes by market news reporters in
several locations. The IMPS cuts were developed and weights of the cuts were
obtained to provide useful data for industry and to substantiate the draft IMPS
cutting styles for carcasses of different weights. The draft IMPS are currently
awaiting review and release by AMS, probably by early summer, 2000.
Some of the more innovative cuts that were developed for goat carcasses
may be adapted for the other red meat species IMPS. The survey of industry
personnel provided an indication of the usefulness of the project and its
results. The project provided a basis for establishment of uniform criteria for
selection and classification of live goats and goat carcasses, developed a
system of IMPS cuts to facilitate marketing of goat meat in institutional
purchasing channels, and validated the research and development results through
interviews with personnel representing all aspects of the goat industry.
Acknowledgments
State funds for this project and publication were matched with Federal
funds under the Federal-State Marketing Improvement Program for the Agricultural
Marketing Service, U.S. Department of Agriculture, as provided by the
Agricultural Marketing Act of 1946. This project was a joint effort among
investigators from the LSU Agricultural Center Louisiana Agricultural Experiment
Station; Southern University College of Agriculture, Family and Consumer
Sciences; Louisiana Department of Agriculture and Forestry; and USDA
Agricultural Marketing Service. Special appreciation is expressed to Dave
Foster and Mike Windham for live goat and carcass grading for the project and to
Orlando Phelps for development of the draft IMPS.
Dr. Frank Pinkerton may be contacted via e-mail at the_goatman@intrastar.net
|