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OCR for page 332
Possible Impacts of Changes
in USDA Grade Standards and
Labeling/~dentification Procedures
G. C. SMITH
U. S. Department of Agriculture (USDA)
grades for carcasses of red meat animals are
based on criteria presumed to be related to
palatability (flavor, juiciness, and tender-
ness) of the meat when cooked and on
estimations of relative curability (yield of
trimmed cuts from the carcass). Nomencla-
ture for the grading systems is not identical
for beef, pork, and lamb; but, in general,
words (for example, Prime, Choice) are used
to characterize palatability and numbers (for
example, 1, 4) are used to inclicate curability.
Relative palatability assessments for beef
and lamb are assigned by USDA graders
using a hierarchical arrangement of word
descriptors wherein the USDA quality grade
names Prime, Choice, Goocl/Select, ant]
Standard for beef; Prime, Choice, Good,
and Utility for lam~indicate the relative
level of palatability or the relative proba-
bility that a specific piece of meat will be
flavorful, juicy, and tender. A leg roast from
a U.S. Prime grade lamb should be more
flavorful, juicy, and tender than a leg roast
from a U.S. Choice grade lamb; the prob-
ability of obtaining a steak that is bland,
dry, and tough should be greater if it is
from a U.S. Goocl/Select grade beef carcass
332
than if the steak is from a U. S. Prime grade
beef carcass. Pork quality is not equated
hierarchically. Rather, a bipartite system is
used in which quality is judged to be either
"acceptable" (in which case the carcass is
assigned the grade prefix "U. S." ant] a
number 1 through 4 clepending on its
relative cutabflity) or "unacceptable" (in
which case the carcass is assigned the gracle
designation U.S. Utility, regardless of its
relative curability, and thus there is no
numerical suffix).
The USDA meat grading service for red
meat animals was instituted as a means for
setting and reporting prices of commodities
in the wholesale meat trade. It eventually
evolved to facilitate trailing in live animals
and merchandising of retail cuts. Meat grad-
ing was made compulsory under the Office
of Price Administration during World War
II and then again, under the Office of Price
Stabilization (luring the Korean conflict, but
not between those periods or since. In 1946,
the program was authorizer] by the Agri-
cultural Marketing Act and was made vol-
untary; packers who wished to use the
grading service had to pay for it. The grades,
assigned by USDA graders acting in the
OCR for page 333
GRADE STANDARDS AND LABELING
role of a third party, identify the quality/
curability of meat for wholesalers and re-
tailers who purchase it without previously
viewing it. In 1984, 65.1 percent of steer
ant] heifer beef (53.3 percent of total beef)
in the U.S. federally inspected slaughter
was officially graded and stamped; of that,
3 percent was Prime, 93 percent was Choice,
ant] 4 percent was Good, while 3 percent
was yield grade 1, 42 percent was yielc!
grade 2, 49 percent was yield grade 3, and
5 percent was yield grade 4. Of the 12
billion pounds of red meat (beef, lamb, calf,
and veal) that was officially graded and
stamped in 1984, more than 90 percent was
beef.
Assurance of wholesomeness and freedom
from disease attributed to red meat by
USDA inspection floes not relate to its
grade, but USDA grades are assigned only
if a carcass has passed inspection. USDA
policy is that beef, pork, and lamb can be
graded only as carcasses to ensure that
grading decisions are accurate and consist-
ent; thus, grading is done only at the slaugh-
ter site. Once the meat has been cut up
and packaged for sale, its equivalent carcass
gracie cannot be determinecI.
Cutability ("yield") grades are in numer-
ical order: USDA yield gracle 1 signifies the
highest comparative curability (yield of closely
trimmed wholesale or retail cuts as a per-
centage of carcass weight); yield gracle 4 for
pork carcasses or 5 for lamb and beef car-
casses denotes the lowest relative cutability.
For pork and beef carcasses, the USDA
quality and yield gracles are said to be
"coupled"; that is, neither grade can be
assignee! without the other. The grading
systems are "uncoupled" for lamb carcasses;
a lamb carcass can be assigned a quality
grade, a yield gracle, or both quality and
yield grades. In practice, lamb carcasses are
seldom yield graded because the industry
does not use yield gracles in the determi-
nation of trading price.
Trading of cattle and sheep and beef,
lamb, and mutton carcasses and wholesale
333
cuts relies heavily on USDA quality/yield
grading. For example, price quotations for
cattle coming from the feecIlot to a slaughter
plant are usually set by specifying a price
per hundrecI-weight for animals that are
described using a four-part (live weight, sex
class, quality grade, yield] grade) system (for
example, 1,125 pouncis, steers, Choice, yielc]
grade 3). Because descriptions of market
animals depenc] heavily on subjective eval-
uations of live weight, quality grade, and
yield] grade, market reporters often use
ranges in weight, the sex class, an estimated
percentage expecter! to grade U. S. Choice,
and a generalization about yield grades (for
example, 1, 075 to 1,200 pouncls, steers, 65
percent Choice, mostly yield granule 2's with
a few yield grade 4's). Swine and lambs are
similarly described for market reporting
purposes; in fact, grades are much more
useful for describing live pigs and lambs
than for facilitating trading of their carcasses.
When it is to the advantage of the seller,
the USDA quality grade is used to mer-
chandise the commodity. Certain restau-
rants, steakhouses, supermarkets, ant! the
like advertise and identify beef or lamb that
is U.S. Prime or U.S. Choice, but termi-
nology related to USDA quality grade is
never specified for pork. USDA quality
gra(le names are imprintecl, using purple
ink, on the surface of beef carcasses and
lamb carcasses, but essentially are never
imprinted on pork carcasses.
To imprint the USDA gracle name, a
round metal wheel (known as a grade roll)
with a series of identical official USDA
shields on its outer surface is continuously
coated] with purple ink and used to mark
the carcass at strategic locations. The wheel
is rolled down the length of the carcass and
across it so that the USDA stamp appears
on almost every solid-muscle retail cut that
can be obtained from that carcass. (A beef
ribeye roll is a solid-muscle retail cut but
would not show the gracle roll without
special care.) Beef en c] lamb carcasses that
are not officially graded are clescribed in
OCR for page 334
334
meat trade vernacular as "No-Roll" car-
casses. Pork carcasses are almost never
graded for quality or yield ant! are not often
sold as intact carcasses to wholesalers and
retailers because so many of the cuts for
example, the belly, jowl, picnic shoulcler,
ham, ant] clear plate are usually cured and
smoked before retail sale and because the
two major wholesale cuts (Boston butt ant!
loin) that are sold fresh (unprocessed) have
heavy layers of subcutaneous fat and skin
that are removed before preparation of retail
cuts.
Essentially all beef and lamb carcasses
are presented to USDA officials for gracling;
but only those that qualify for merchantable
grades Prime and Choice quality grades
and, for beef, 1, 2, ant! 3 yield grades are
normally identified with official gracle stamps.
Over the years, quality grade names of
GoocI/Select, Standard, ant! Utility have
come to signify inferior quality; and yield
gracle designations of 4 and 5 result in
punitive price discounts, so packers seldom
if ever allow such words or numbers to be
affixed to carcasses. Most packers have a
category of carcasses that they call No-Roll
and they attempt to merchandise the con-
glomerate as one kind of carcass. Depending
on company policy, carcasses from young
intact males (bullocks or lambs) and car-
nasses from females of advanced are ("heif
erettes or young cows and yearling ewes,
for example) may also be included in the
product mix of No-Rolis; as a result, the
palatability and cutabflity of No-Roll beef
and lamb may be quite variable within and
between lots and over time.
USDA quality grades for beef carcasses
are baser! on evaluations of (1) the estimated
physiological age of the animal at the time
of slaughter, called "maturity" and assessed
by looking at the color and texture of the
exposed ribeye muscle (Iongissimus dorsi
muscle exposed by cutting between the 12th
and 13th ribs of the carcass), and by eval-
uating the amount of ossification of cartilage
APPENDIX
in the skeletal system and (2) the estimated
amount and distribution of intramuscular
fat (called "marbling") in the exposed ribeye
muscle. The more youthful the carcass and
the more heavily marbles! the ribeye mus-
cle, the higher the USDA quality grade for
beef.
USDA quality gracles for lamb carcasses
are based on evaluations of (l) the estimated
physiological age of the animal at the time
of slaughter, called "maturity" and assessed
by looking at the color of muscles on the
interior surfaces of the body cavity and by
evaluating color ant! shape of rib bones ant}
ossification of the cannon bones; (2) the
amount and distribution of streaks of fat
across the surface of the primary flank mus-
cle (in the abdominal cavity of the carcass),
which is an indirect estimate of the amount
of marbling expected in the ribeye muscle;
and (3) the conformation of the carcass,.
evaluated as the width, bulge, and plump-
ness of muscles and thus of the muscle/bone
ratio of the carcass. The more youthful the
carcass, the more extensive the streakings
of fat in the flank, ant] the higher the muscle/
bone ratio, the higher the USDA quality
grade for lamb.
Quality is assessed for pork carcasses
based on evaluations of (1) acceptability of
the belly for bacon production, determined
by its thickness and firmness; (2) color of
the muscles on the interior surfaces of the
body cavity; (3) firmness of the fat and lean
throughout the carcass; and (4) the amount
and distribution of streaks of fat across the
surfaces of the primary flank, secondary
flank, ant] intercostal muscles. If the belly
is firm and thick, the muscles grayish pink
or darker, the fat and lean at least slightly
firm, and the fat streaking present in at least
Slight amounts, the carcass is considered
"acceptable" in quality and is then yield
graded. The crux of the quality grading
systems tor carcasses of red meat animals is
intramuscular fat content (the higher the fat
content in the muscles, the higher the
OCR for page 335
GRADE STANDARDS AND LABELING
quality grade), because marbling improves
the chance that the meat will be flavorful,
juicy, and tender when cooked.
USDA yield gracies for beef carcasses are
based on evaluations of (1) carcass weight;
(2) surface area of the ribeye muscle at the
juncture of the 12th ant] 13th ribs; (3)
thickness of external fat at the specified
point over the ribeye exposed in the cross-
sectional surface exposer] between the 12th
and 13th ribs; and (4) the estimated per-
centage weight as kidney, pelvic, and heart
fat. At a given carcass weight, the larger
the ribeye, the less the external fat thick-
ness; and the lower the percentage of kid-
ney/pelvic/heart fat, then the lower the yield
grade number (thus, the higher the cuta-
bility).
USDA yield grades for lamb carcasses are
based on evaluations of (1) bulge and plump-
ness of muscles in the leg, (2) thickness of
external fat at the specified point opposite
the ribeye muscle between the 12th and
13th ribs, and (3) the estimated percentage
of carcass weight as kidney and pelvic fat.
The more muscular the leg, the less the
external fat thickness; and the lower the
percentage of kidney and pelvic fat, the
lower the yield grade number (thus, the
higher the cutabflity; in other words, the
greater the amount of the carcass that can
be sold as trimmed, boneless cuts).
Cutabflity in pork carcasses is determiner]
by assessments of (1) length or weight of
the carcass, (2) thickness of external fat at
the specified point on the midline of the
carcass, and (3) bulge and plumpness of
muscles in the carcass. At a given carcass
weight or length, the less the external fat
thickness and the more muscular the car-
cass, the Tower the yield! grade number
(thus, the higher the curability; in other
words, the greater the amount of the carcass
that can be sold as partially trimmed, bone-
in, ham/Ioin/shoulcler). The crux of the yield
grading systems for carcasses of red meat
animals is the muscle/fat ratio-the higher
335
the fat content of the carcass (as external,
seam, and body cavity depots), the higher
the yield gracle number (thus, the lower the
cutabflity). Yielc! gracle predicts the amount
of the carcass that will be salable as whole-
sale (pork) or retail (beef ant! lamb) cuts and
is intended for use by the packer, whole-
saler, and retailer but never by the con-
sumer (since by the time the consumer sees
the piece of meat, its excess fat has been
removed).
Although the USDA quality and yield
grade systems may appear to be paradoxi-
cal one (quality grade) encourages fatness,
the other (yield grade) penalizes fatness-
it must be understood that fat is deposited
in an animal's body in a number of specific
anatomical locations called fat depots and
that the depots are filled with fat in an
ordered sequence. The fat depots are (1)
the mesenteric region around the stomach
and intestines; (2) those adhering to the
thoracic/abdominal/pelvic cavities around
the heart as a sac, around the kidney as a
capsule, and lining the pelvic cavity; (3) the
subcutaneous region under the skin of the
live animal anal over the external surfaces
of the skinned carcass; (4) the intermuscular
seam areas between two muscles and be-
tween a muscle and bone/cartilage; an(l (5)
the intramuscular sites within muscles.
Accumulation of fat in depots (1), (2), (3),
and (4) listed above is of little or no conse-
quence in assessing prospective flavor, jui-
ciness, or tenderness of the muscles from
that carcass; deposition of fat as marbling,
in fat depot (5) above, is positively related
to palatability of cooked beef, pork, and
lamb. Unfortunately, in most red meat an-
imals, deposition of fat in depots 1 through
4 occurs earlier in the animal's life than
deposition of fat as marbling, so that gen-
erally by the time the animal has deposited
enough intramuscular fat to qualify for the
highest USDA quality grades, it has depos-
ited too much fat in the body cavity, be-
tween the muscles, and over the exterior of
OCR for page 336
336
the skinned carcass to have desirable com-
position (proportions of muscle and fat).
Also, as animals are fed high-concentrate
diets for progressively longer periods of time
to increase chances that they will have
enough marbling to grade Choice or Prime
(for lamb or beef, but not for pork), their
yield grade suffers because of a greater
probability that the trimmable fats are pres-
ent in excessive quantities.
The USDA quality grading system per se
can be a deterrent to increasing leanness of
beef cattle and their carcasses because in
certain market situations it encourages over-
fattening. Such is not the case for lambs,
because they can attain the Choice grade
without ever having been fed grain, or for
swine, because the pork grading system is
not hierarchical and it is not used by the
trade to determine prices. For beef, Choice
carcasses are worth 1 to 3 cents more per
pound ($6 to $24 per carcass) than Good/
Select carcasses most of the time, but at
times-can be worth substantially more than
Good/Select carcasses, with premiums for
Choice sometimes reaching 7 to 11 cents
per pound ($42 to $88 per carcass). Such
differences, though they occur infrequently,
provide incentive to overfeed] cattle.
For some breeds or crossbreeds of cattle
and for some lines/strains within breeds and
crossbreeds, increasing the time-on-feed wiD
result in increased deposition of marbling,
but there are cattle that do not have the
inherent ability to deposit intramuscular fat
ant! that will not achieve the level of mar-
bling needed to qualify for the Choice grade
regardless of length of feeding period. In
these cases, it is futile to extend time-on-
feed in the hope of increasing value by
improving the USDA quality grade. Rather,
the cattle simply get fatter in depots that
detract from leanness, lower the yield grade
number, and make the end product less
acceptable to consumers.
However, lengthening time-on-feec] al-
most always increases the "dressing per-
centage" (the ratio of carcass weight to live
APPENDIX
weight, expressed in percentage points) for
cattle, swine, and lambs, regardless of their
genetic capability to respond to beetling by
depositing more intramuscular or superficial
streaks of fat. The extent to which meat
packers encourage producers to lengthen
time-on-feec! in order to (1) increase the
number of animals achieving a certain USDA
quality gracle versus (2) increase dressing
percentage and thereby decrease the cost
per pound of the carcass differs depending
on the genetics of the livestock involved
and cannot be precisely assessed because
quality grade and dressed yield are highly
related to each other.
When buyers for meat packers purchase
cattle, sheep, and swine on a live-animal
basis, they do so by deciding on a price per
pound alive that will minimize the cost per
pounce of the carcass and that is still high
enough to beat out other buyers. Price
determination starts with estimations of car-
cass value plus drop (eclible and inedible
offal) value minus cost to slaughter/fabricate;
that sum is (livi(led by estimated carcass
weight to obtain carcass value per pound.
The price a buyer will then pay per pound
for a live animal is determined by multiply-
ing carcass value per pound times the (lress-
ing percentage; as the ciressing percentage
increases, the price paid increases. Knowing
that the dressing percentage increases as
the fatness ofthe animal increases, the buyer
will push for greater fatness (by encouraging
that the animals be fee] longer) up to, and
sometimes beyond, the point at which a
yield grade line (between 3 and 4, for
example) will be crossed at a punitive dis-
count. For example, suppose a buyer eval-
uates a pen of lambs that he estimates will
have a dressing percentage of 50. If he bills
75 cents per pound for the live animals and
they dress 50 percent, the carcasses will
have cost him hanging on the rail $1.50
per pound. If he believes the lambs could
be fed an additional 3 weeks without be-
coming yield grade 4's and because they
are much fatter~ress 54 percent, he will
OCR for page 337
GRADE STANDARDS AND LABELING
encourage the producer to feed them longer,
because although he will still pay 75 cents
per pound alive, he can rail the carcasses
at a cost of $1.39 per pound. Unfortunately,
though, the composition of the carcasses of
lambs fed for the additional 3 weeks will
have suffered greatly. The same scenario
applies for beef; additional time-on-feed to
increase ciressing percentage and decrease
carcass cost has been abetted by the fact
that, until very recently, primal cuts of beef
moved freely in the tracle with as much as
1 inch of external fat covering.
If dressing percentage (and carcass cost)
could somehow be removed from the pricing
logic currently used for the purchasing of
red meat animals, the incentive to feed the
animal longer would be greatly lessened.
In fact, the practice of fattening the animal
to increase dressing percentage has worked
only because wholesalers and retailers tol-
eratec] the additional fat knowing they could
pass it along to their customers, the ens]
product consumer. As that changes and it
is doing so rapidly with the advent of quarter-
inch fat trim at retail and adoption of three-
eighths to one-halfinch fat trim at the packer
level the impetus to minimize carcass cost
by encouraging overfattening to improve
dressing percentage will decline. Indeed
the dressing percentage/carcass cost pricing
logic used routinely in the trading of live
red meat animals is a deterrent to improving
leanness, as are the USDA quality grading
standards. So long as feeders clemanc] to
sell cattle on a live weight basis rather
than on the basis of carcass grade and
weight~lressecl yield/carcass cost is an im-
perative component of the pricing system.
There remains incentive to increase the
fatness of rec] meat animals if it is true that
as fatness increases, the flavor, juiciness,
and tenderness of cooked meat improves.
There is, however, enough genetic varia-
bility among swine, sheep, and cattle to
make it possible to select animals that will
deposit marbling in the muscles to a degree
sufficient to qualify them for the U. S. Choice
337
or even Prime grades without having de-
posited excessive quantities of subcuta-
neous, intermuscular, or kidney/pelvic/heart
fat. Also, U.S. consumers are attuned to
the presence of certain quantities of fat
intermingled with lean such that "accepta-
ble" or superior palatability in beef, pork,
and lamb depends on deposition of marbling
in specific amounts. This is especially the
case for customers in hotel, restaurant, ant]
foot] service establishments who, because
they pay high prices for a meal, expect
consistently high palatability in the meat
they are served. Therefore, meat purveyors
sell Prime or Choice beef ant] lamb to
restaurateurs and fooc3-service-unit opera-
tors who serve affluent clientele. Because
such products are in limiter] supply yet in
substantive demand, their prices are higher
than those of beef and lamb of lower quality
gracles. Price incentives encourage packers
an(1 feeders to strive to produce beef of the
highest grades. For most animals, the like-
lihood that they will grade Prime or Choice
is improved with increased fee(ling time.
That being the case, cattle producers will-
especially if grain prices are low feed their
cattle longer than is economically optimal
from growth, efficiency, and carcass com-
position standpoints, striving for the mini-
mum intramuscular fatness required to
achieve the U. S. Choice grade. The Choice
grade is achieved in beef when a chemical
fat level of about 4.3 percent is attained in
the longissimus dorsi, or "ribeye," muscle.
That fatness level is very low ant] well within
caloric constraints for a healthful (lies. How-
ever, by the time-chronologically or in
time-on-feed that the 4.3 percent intra-
muscular fat level is attained, the entire
carcass will be composed of 25 to 40 percent
fat (subcutaneous, intermuscular, intramus-
cular, ant! kidney/pelvic/heart). Because
deposition of fat in subcutaneous, inter-
muscular, and kidney/pelvic/heart regions
usually prececles deposition of fat as mar-
bling, feeding cattle to achieve some set
point in marbling deposition will far too
OCR for page 338
338
often result in production of carcasses that
are excessively fat.
A possible way to recluce the overall
fatness of lamb and beef carcasses is to lower
the marbling requirement for each USDA
quality grade. If, for example, the minimum
marbling requirement for the U. S. Choice
grade in beefwere reducecI from 4.3 percent
(described as a Small amount of marbling
in official USDA quality grade stan(lards) to
3.0 percent (a Slight amount), time-on-feec3
could be reduced by about 30 days and
percentage of fat in the carcass by about 10
percentage points. However, this solution
ignores the fact that beefof3.0 to 4.3 percent.
intramuscular fatness is currently available
(as USDA Good/Select grade beef) yet has
found only limited consumer demand.
The National Cattlemen's Association
(NCA) concluded in January 1986 that (1)
consumers want lean beef regarcIless of
USDA quality gra(le, (2) changing the USDA
beef quality grading standards is not a pre-
requisite for producing leaner beef, (3) the
retail consumer market is segmented be-
tween those who emphasize taste and those
who emphasize leanness, (4) combining the
Choice and Good/Select grades into one
graclelwould recluce the industry's ability to
market beef effectively to either market
segment, and (5) any attempt to change the
USDA beef quality grading standards will
be interpreted by consumers as negative.
In 1981, NCA asked USDA to allow part of
the Good/Select grade of beef to be desig-
nated Choice (because such beef was leaner
but still tasty); USDA rejected the idea
partly because of opposition by some re-
tailers, consumers, and cattle producers but
largely because of opposition by restaura-
teurs and purveyors as well as consumer
groups who contended that the proposal
was a ploy to sell lean meat at higher prices.
Nevertheless, for more than 10 years
consumer advocates have been calling for a
change in the USDA beef quality grading
standards so that the system will not (lis-
criminate against leaner beef. Adclitional
APPENDIX
consumer efforts have called for a complete
overhaul of USDA grades to reflect nutri-
tional content of meat rather than the sub-
jective characteristics of taste. In 1974, the
National Consumers League recommended
that the USDA beef quality gracling system
be modified so that one additional grade
designation be added between Choice and
Good/Select in order to "encourage the
production ant] marketing of leaner beef
which uses less grain, costs less to procluce,
and at the same time would allow prices to
reflect this producer-cost reduction." Six
years later, the Community Nutrition In-
stitute stated that"the marketplace is ready
and eager to accept a leaner, cheaper beef
that must be promoted without imposing
subjective opinions of eating pleasure" and
that "the discrimination against lean beef
inherent in the nomenclature of the present
system could be eliminated by developing
a new gracle name They suggested 'USDA
Choice Lean,' 'USDA Choice Light,' or
'USDA Lean Choice'] to replace USDA
Good." In February 1986, the Public Voice
for Foot] and Health Policy suggested that
USDA could either create a new grade (e.g.,
"Choice Lean," "Leaner Choice") that is
lower in fat than Choice but that is clearly
palatable and that could perhaps replace
Choice, or restructure the entire quality
grading system to reflect nutritional content
of the meat.
In the 1985 National Consumer Retail
Beef Study, beef of two quality levels was
offered to participants (U. S. Choice as Choice
and U.S. Good as Select). Overall accept-
ability of the two kinds of beef was the
same, but for different reasons. Consumers
who preferred Choice beef did so because
of its advantages in palatability, while those
who preferred Select beef clic] so because
of its advantages in leanness. Choice beef
was recognized as being somewhat fatter
and Select beef as somewhat less desirable
in palatability; yet consumers preferring
each type of beef were willing to make the
trade-oR to achieve the attribute most im
OCR for page 339
GRADE STANDARDS AND LABELING
portent to them. (A more thorough discus-
sion of the National Consumer Retail Beef
Study is given by Saved and Cross in this
volume. ~
Results of the National Consumer Retail
Beef Study were sufficiently encouraging to
prompt the Public Voice for Food ant!
Health Policy to petition USDA to "chance
the name of the 'Good' federal beef gracle
to reflect that it is leaner than 'Prime' or
'Choice' and to stop discrimination against
lean beef." Public Voice asked that the wore!
"Select" replace the word "Good" as a grade
name for beef carcasses having a Slight
amount of marbling en c] thus containing 3.0
to 4.3 percent fat in the longissimus dorsi
muscle. The USDA ruler! in late September
1987 to implement the name change from
Good to Select, effective November 23,
1987.
The National Academy of Sciences (NAS)
Committee on Technological Options for
Nutritional Improvements in the Food Sup-
ply with Emphasis on Animal Products
concluded that such change in grade no-
menclaturc- though purely semantic
would be in the best interest of all con-
cerned. At present, essentially no beef is
officially identified as U. S. GoocI; as a result.
those who might wish to buy such beef
cannot find it so identified. Packers sell
the equivalent of U. S. Good beef as a part
of the No-Roll category, for which there is
no minimum quality indicator (marbling or
maturity) level. As a result, no true test of
the acceptability of Good grade beef to
consumers can be achieved because the
beef is in a mixture of the commodity (No-
Rolls) that is highly variable in palatability.
In May 1986, the American Meat Institute
supported the Public Voice objective of
changing the nomenclature of the Good
grade to give leaner beef a more positive
image. The NAS committee also consiclered
recommending changes in the U.S. stancI-
ards for beef grading that would parallel
those made in 1972 by Canada. The Cana-
dians premised their changes in beefgrading
339
on the following conclusions: (1) Although
fatness helps to ensure tenderness and fla-
vor, beef does not have to be fat to be
flavorful ant] tender; (2) it is wasteful and
inefficient to produce overeat cattle only to
have their carcasses trimmed to retail stand-
ards; (3) a potent force encouraging excess
fatness is the obvious desire of packer buyers
to purchase cattle as cheaply as possible on
the rail by increasing dressing percentages
so as to lower carcass cost; and (4) changes
in cattle through breeding would be a long
ant] difficult process and rapid changes in
carcass characteristics through changes in
cattle feeding are unlikely, so by far the
most important change that could be made
a change that would! result in an immediate
and dramatic response would be to "har-
vest" the cattle as they reach the point of
optimum finish. Before 1972, the Canadian
beef carcass grading system was similar to
that currently used in the United States; in
1972, the Canadians adopted a system based
on dual gracing. This system consists of five
quality/maturity designations (A, B. C, D,
E) and four subgrades (1, 2, 3, 4) baser] on
single fat thickness measurements taken
opposite the ribeye muscle between the
11th and 12th ribs. Since implementation
of those gracle standards, the percentage of
beef carcasses grading A-1 has increased
from about 32 percent in 1972 to about 52
percent in 1986. The primary (difference
between quality grading in Canada versus
that in the United States is the essential
disregard of marbling as a grade-determin-
ing factor in the Canadian system.
The NAS committee received testimony
from Canadian officials acknowledging that
they have a perceived and possibly real
problem with unsatisfactory tenderness, jui-
ciness, ant] flavor of their beef and that this
inadequacy in eating satisfaction may well
be the result of ignoring marbling in (leter-
mining quality grade. Much of the beef sold
to the food service trample in Canada is Prime
or Choice beef produced in the United
States. Therefore, the NAS committee could
OCR for page 340
340
not support any change that would eliminate
marbling as a gracie-determining factor and
thereby eliminate the ability of the industry
to differentiate beef of the present Prime,
Choice, Good/Select, and Standard grades.
Because some consumers want and are will-
ing to pay for a product having the charac-
teristics of and iclentified as Prime or Choice,
it is best to continue such identification
protocol. As long as products are identifier]
as such, consumers can find them and select
or reject them thereby exercising their
right to an option in the marketplace.
A goal, then, of the NAS committee was
to ensure that American consumers have
the opportunity to exercise personal in-
formec! choice in the selection of foods to
include in their diet and that such choices
are identifiable and available. A review of
the research at the Texas Agricultural Ex-
periment Station (reported in more cletail
by Savell and Cross in this volume) indicates
that a minimum level of 3 percent chemical
fat in the ribs and loins of cattle, swine, and
sheep is necessary to ensure acceptable
palatability in beef, pork, and lamb. They
contend that, in terms of nutritional merit,
the maximum level of intramuscular fat that
should be in the rib and loin cuts is 7.0
percent. A "Winslow of acceptability" (3.0
to 7.0 percent intramuscular fat) is thus
created that considers diet/health/nutrition
as well as flavor/juiciness/tenderness factors.
Within that window are two other thresh-
olds of chemical fatness associate<] with
progressive increases in palatability at ap-
proximately 5 percent chemical fat (mid-
point of the Small amount of marbling) and
at approximately 7 percent chemical fat (at
the lower end of the Moderate amount of
marbling).
These hierarchical rankings in palatability
associated with increasing levels of intra-
muscular fatness would allow segmentation
of the beef, pork, and lamb supplies into
expected palatability groupings that would
facilitate targeting and servicing the wants
and needs of a segmented consumer market
APPENDIX
with varying tastes. Identification of beef
with 3.0 to 4.3 percent intramuscular fatness
with a new grade designation Select will
make it possible for those who seek beef of
that kind to find it and might encourage
grocers/restaurateurs to stock it. Because
this change will create "identifiable con-
sumer choices" and give customers the
option to buy leaner beef in the market-
place, the committee encourages merchants
to promote the sale of Select beef as an
alternative or adjunct to beef of the Choice
gracie. If beef of that fatness level is ac-
ceptable to consumers, its production will
be encouraged by price, encouraging a sup-
ply commensurate with the demand ex-
pressed at that price.
The committee evaluated the trend to-
ward promotion of red meat products la-
beled "Natural" ant! "Light" (with the var-
iant "Liter". The exact implications of such
claims are in the purview of the USDA
Standards and Labeling Division, Foot! Safety
ant] Inspection Service (FSIS). While the
term "Natural" is being promoted by some
elements of the industry as representing
meat from animals that have not been ex-
posed to drugs, growth promotants, hor-
mones, antibiotics, pesticides, or feed ad-
clitives and by others as representing meat
from animals that are reared in open spaces
(as opposed to feedlots) ant] fed forages/
roughages (rather than grains), such con-
notation is not collided in state or federal
regulations. USDA FSIS Policy Memo 055
states that the term "Natural" may be used
on the label of meat and poultry products
providing that (1) the product does not
contain any artificial flavoring, coloring in-
gredient, chemical preservatives, or any
other artificial or synthetic ingredient and
(2) the product and its ingredients are not
more than minimally processed ("minimal
processing" may include smoking, roasting,
freezing, drying, fermenting, and grinding).
This being the case, all fresh red meat could
be labeled "Natural."
The committee considers present use of
OCR for page 341
GRADE STANDARDS AND LABELING
the term "Natural" by certain producers/
processors to connote that meat from ani-
mals produced by use of health and growth/
efficiency aids is somehow unnatural and
thus unhealthy to be misleading and inap-
propriate. Because it is not in the best
interest of the consumer to create unwar-
ranted fear about the safety/healthfulness of
the foot! supply, the committee recom-
mends that use of the term "Natural," in
the manner that some promoters now use
it, not be allowed.
By the same token, the terms "Light"
and "Lean" are being used inappropriately
by some elements of private enterprise to
imply superiority in leanness when such is
not the case. USDA FSIS Policy Memos
070A ant! 070B state that the terms "Lean"
and "Low Fat" can be used only on meat
and poultry products containing less than
10 percent fat and that the terms "Light,"
"Leaner," and "Lower Fat" can be used
only on products that contain at least 25
percent less fat than the majority of such
products in the marketplace. Before issu-
ance of these policy memoranda, fat claims
such as "Light," "Lean," and "Extra Lean"
could! be used interchangeably on meat and
poultry products containing 25 percent less
fat than a comparable product and on prod-
ucts containing no more than 10 percent
fat. The committee is concerned about the
use of descriptive adjectives like "Light,"
when verification of relative fatness/leanness
is made at the carcass level (comparing
carcass traits of two kinds of beef, pork, or
lamb), because retail cuts from fat or lean
carcasses can be either fat or lean (and not
cli~erent from each other) after fabrication
and trimming at the retail level. The com-
mittee strongly urges USDA not to allow
certification as "Light" or "Lean" on the
basis of carcass (lata an(l to restrict use of
such terminology to products as they would
be presented to consumers at the retail
level. Fresh rec] meats or poultry, if they
are to be labeler] as "Light" or "Lean" at
the retail level, must in fact be low in fat
341
or the industry will super further loss of
consumer confidence. The USDA should
consider (leveloping a program to certify
fatness of wholesale and retail cuts and
should offer a "Certi-Light" or "Certi-Trim"
specification that industry could use as a
third-party verification that fatness floes not
exceed some critical set point (for example,
no more than 10 percent chemical fat). Such
USDA certification, although it might be
perceives! as government intervention, would
make possible industry standardization of
the term "Light" ant! would] make feasible
equal opportunity for market entry by firms
of small, medium, or large size. UnIess
USDA controls the use of terms like "Nat-
ural" and "Light," these terms will soon
lose credibility and the red meat industry
will lose the opportunity to capitalize on
well-documented desires of certain seg-
ments of the consumer market to purchase
lower calorie or residue-safe meat products.
The committee also supports action to
uncouple the yield grading/ quality grading
of beef carcasses. At present, carcasses that
are categorized as No-Roll because they
have too little marbling to grade Choice are
not identified for curability (specifically,
they are not yield graded). Those carcasses
that are categorized as No-Roll because they
have too much fat to qualify for the 3 or
better yield Grade are not identifie(1 for
expected palatability (specifically, they are
not quality graded). This disrupts the com-
municative function of the grappling system
ant] is thus a deterrent to increasing leanness
of cattle. Furthermore, carcasses that are
trimmer] before presentation for grading
cannot be accurately yield grader] and so
are ineligible for quality grading. Some
packers would remove, at the time of slaugh-
ter, most or all of the subcutaneous or
ki(lney/pelvic/heart fats from beef carcasses
that were too fat if USDA would allow such
carcasses to be quality gradecI.
There is presently no disincentive in the
U. S. marketing system to prevent the feecI-
ing of grain when it is cheap-to the point
OCR for page 342
342
that it causes overfattening of red meat
animals. Until such disincentive is in placc
and a governmental policy change may be
necessary to effect such a change the in-
dustry will continue to produce animals with
too much fat. The quickest available means
to make beef, pork, and lamb leaner and to
discourage overfeeding and excessive fat-
tening would be to allow packers to remove,
during the slaughter/ciressing process, all
external fat in excess of that amount (for
example, one-fourth inch) that can remain
on retail cuts.
In late 1986, the American Meat Institute
(AMI) decided that trimming of retail cuts
to leave only one-fourth inch of external fat,
as initiated by some retailers in 1986, is a
systematic and real improvement and that
the place to accomplish such fat removal is
in the packing plant-on the slaughter floor.
In November 1986, AMI and NCA members
reviewed hot-fat trimming at the Monfort
of Colorado plant in Greeley and received
results of a Texas A&M University study
evaluating that process. AMI suggested that
use of hot-fat trimming would (1) remove
dressing percentage as a price-determining
factor in purchases of live cattle, (2) dis-
courage overfeeding and overfattening of
cattle, (3) allow for removal of excess fat at
a point where its value (as edible tallow) is
highest, and (4) make possible payment of
the highest prices for the leanest cattle. If
excess external fat is removed on the slaugh-
ter floor ant! cattlemen are paid only for
that amount of fat left on the carcass when
the carcass is weighecl, there will be excel-
lent incentive to not overfatten cattle.
The committee considered AMI's sug-
gestions and, as a result, favors uncoupling
the yield ant] quality grades to allow for
hot-fat trimming of beef carcasses and en-
courages USDA to implement such changes
in gracling protocol.
The yield grades are useful to certain
segments of the beef industry (producers,
packers, wholesalers, purveyors, retailers)
but do nothing to assist the consumer in
APPENDIX
making purchasing decisions that would
benefit from knowledge of relative fatness/
caloric content of meat cuts. The committee
considered numerous options for providing
relative fatness information to consumers
and decided that at least three alternatives
existec! for accomplishing that end. The
information could! be provided by mandating
nutrition labeling for retail cuts, but there
is little evidence that such information would
actually be useful or used. Because con-
sumers make purchasing decisions very
quickly, a system of identification by fatness
level that would carry through the market-
ing sequence and appear at the retail level
in alphanumerical form might be helpful.
For example, in the code A-2-3, A could
indicate maturity of the animal at slaughter,
2 the amount of marbling (or perhaps mar-
bling plus subcutaneous and intermuscular
fat), and 3 the yielc] grade of the carcass.
Identification as A-l-1 would therefore sig-
nify a young animal with a "Moderate"
amount of marbling and very high curability.
Because not every piece of meat from an
A-l-1 carcass would actually be an A-1-1
retail cut, the last number could be dropped
and individual cuts from an A-1 could be
labeled, at the retail meat counter, as A-1,
A-2, A-3, or A-4, depending on their mar-
bling level an(l subcutaneous plus inter-
muscular fat content. More severe trimming
of retail cuts would improve the numerical
gracle, moving it, for example, from A-4 to
A-1 if trimming was severe enough.
A second means for identifying relative
fatness/caloric content of retail cuts might
involve the use of a color system (re(l, white,
blue) or a medal system (gold, silver, bronze)
affixed to retail packages. Such a system
would be based on the identification of three
levels of fatness of retail cuts that would
determine the size of serving that coulc] be
consumed on a daily basis while conforming
to a healthy cliet. Compliance could be
voluntary or mandatory depending on local,
state, or federal ordinances or laws. The
advantage of a color-cocling or medal system
OCR for page 346
346
nective tissue walls on either side of the
deposit are thinned, thereby decreasing
their effective width, thickness, and strength.
Lubrication theory. Intramuscular fats,
present in and around the muscle fibers,
lubricate the fibers and fibrils ant! so make
for a more tender and juicier product that
potentiates the sensation oftenderness. Thus,
tenderness is closely associates! with juici
ness.
Insurance theory. The presence of higher
levels of marbling allows the use of high-
temperature, cry-heat methods of cooking
and/or a greater degree of doneness without
adversely affecting the palatability of the
meat. Marbling thus provides some insur-
ance that meat that is cooked too long, too
rapidly, or incorrectly wfl} still be palatable.
Relationship Between Fat and
Tenderness
Based on their review of the data, Smith
and Carpenter (1974) found that fatness had
a moderate relationship to tenderness in
pork and a low to moderate relationship to
tenderness in beef and lamb.
Juiciness
Juiciness is made up of the combiner!
effects of initial fluid release and the sus-
tained juiciness resulting from the stimu-
lating effect of fat on salivary flow (Weir,
1960~. These two factors can be described
as follows (Bratzler, 1971~: (1) initial fluid
release the impression of wetness per-
ceived cluring the first chews, produced by
the rapid release of meat fluids, and (2)
sustained juiciness the sensation of juici-
ness perceived during continued chewing,
created by the release of serum ant! due,
in part, to the stimulating effect of fat on
salivary flow. According to Pearson (1966),
the initial fluid release is affected by degree
of aloneness and method of cooking, while
sustained juiciness is relatecl to intramus-
cular fat content.
Fat may affect juiciness by enhancing the
APPENDIX
water-holding capacity of meat, by lubri-
cating the muscle fibers cluring cooking, by
increasing the tenderness of meat and thus
the apparent sensation of juiciness, or by
stimulating salivary flow cluring mastication
(Smith and Carpenter, 1974~.
Relationship Between Fat and Juiciness
According to Smith and Carpenter (1974),
fatness has a moderate relationship to juic-
iness in lamb, a moderate to high relation-
ship to juiciness in pork, and a low to
moderate relationship to juiciness in beef.
Flavor
Hornstein (1971) believes that fat may
affect flavor in two ways: (1) Fatty acids, on
oxidation, can produce carbony! compounds
that are potent flavor contributors, and (2)
fat may act as a storage clepot for odoriferous
compounds that are releaser! on heating.
Volatile compounds released from fat or
producer] from triglyceride or phospholipid
fractions may be responsible for the species-
specific flavors of beef, pork, and lamb.
Smith and Carpenter (1974) stated that
although the basic meaty flavor is nonlipid
in origin, some quantity of fat is uncloubtecily
necessary to make beef taste rich, full, and
"beefy." Smith et al. (1983) stated that U.S.
Department of Agriculture (USDA) beef
quality grades are related to flavor of beef
because grade indirectly assesses the extent
to which flavor and aroma compounds are
likely to be present in the meat.
Relationship Between Fat and Flavor
Fatness has a low relationship to flavor
in lamb and a low to moderate relationship
to flavor in pork and beef (Smith and Car-
penter, 1974).
SPECIFIC RESEARCH ON PORK,
LAMB, AND BEEF PALATABILITY
This section covers pertinent information
on species-specific research that helps to
OCR for page 347
ROLE OF FAT
determine how much fat is necessary for
acceptable palatability. The work that is
reported is from the Texas Agricultural
Experiment Station and represents a portion
of the palatability/grade/ consumer accept-
ance research conducted on pork, lamb, and
beef by the Meats en c] Muscle Biology
Section during the past three decades.
Pork Palatability Research
The study by Davis et al. (1975) with 403
pork loins showed that when three cate-
gories of loins were created baser] on mar-
bling level ("typical-Modest'' or higher,
"typical-Slight" to "Modest-minus," ant]
"Slight-minus" or lower), scores for juiciness
and overall satisfaction were significantly
lower in the "Slight-minus" or lower cate-
gory. Juiciness, tenderness, and overall sat-
isfaction ratings were significantly higher
for chops from loins that were from the
"typical-Modest" or higher category. Davis
et al. (1978), using the same sample of pork
loins used by Davis et al. in 1975, designed
a system for segmentation offresh pork loins
into quality groups of"Superior," "Accept-
able," or "Inferior." Using the sirloin end
as the scoring surface, loins that were light
in color, that were soft, and that had low
marbling scores were rated as "Inferior,"
while those with intermediate color, firm-
ness, and intermediate to high levels of
marbling were rated as "Superior." With
respect to the level of marbling necessary
in pork longissimus dorsi muscle to ensure
acceptable palatability, Davis (1974) rec-
ommendec] between 3.5 and 4.5 percent
intramuscular fat.
Lamb Palatability Research
In a study of lamb rib chops, Carpenter
and King (1965) evaluated the influence of
cooking method, marbling, color, and core
position (for Warner-Bratzler shear cleter-
minations) on tenderness. Chemical fat was
determined on the rib chops and was strat-
ified by marbling score of the longissimus
347
dorsi muscle as follows: Practically Devoid
= 2.05, Traces = 2.49, Slight = 3.15,
Small = 3. 54, Modest = 4.10, Moderate
= 4.79, Slightly Abundant = 4.39, Mod-
erately Abundant = 5.17, and Abundant
= 6.67. Tenderness (as measured by the
Warner-Bratzler shear machine) was most
affected by cooking methoc] and core posi-
tion. Highly significant correlations were
found between tenderness and the fat con-
tent of the longissimus clorsi muscle, but
the coefficients were of low magnitude.
Lamb carcass quality was extensively
evaluated by Smith et al. (1970a,b) and
Smith and Carpenter (1970~. Smith et al.
(1970a), in evaluating the palatability of leg
roasts, found that individual or combined
USDA scores for carcass quality feather-
ing, flank streaking, firmness, and matu-
rity were associated with less than 15 per-
cent of the variation in overall satisfaction
ratings. Segmentation into USDA quality
grades indicated that roasts from Prime
carcasses possessed the highest percentage
of clesirable ratings and the lowest percent-
age of undesirable ratings for juiciness,
tenclerness, and overall satisfaction com-
pared with the other grades evaluated. Small
and inconsistent differences appeared be-
tween roasts from carcasses in the Choice
ant] Goocl/Select grades, but leg roasts from
Utility carcasses were ~lecicle(lly inferior in
palatability to those from the higher USDA
grades.
Smith et al. (1970b), in the companion
study on palatability of rib, loin, and sirloin
chops, fount] that segmentation into USDA
quality grades indicated that chops from
Prime carcasses were superior to those of
the other gracles in percentage of (lesirable
ratings for juiciness, tenderness, and overall
satisfaction. As grade (lecreased from Prime
through Good/Select, there were corre-
sponcling decreases in the proportion of
chops considerecl desirable In Juiciness,
tenderness, and overall satisfaction. With
the exception of scores for tenderness, (lif-
ferences between chops from Good/Select
versus Utility carcasses were small.
. . . .
OCR for page 348
348
When Smith anc] Carpenter (1970) col-
lected chemical data from a sample of car-
casses used in the studies by Smith et al.
(1970a,b), they found that differences in
intramuscular fat were associated with sig-
nificant changes in juiciness, tenderness,
ant! overall satisfaction ratings for all the
cuts studiecI. Based on the conclusions of
three studies, increased fatness was gener-
ally associated with increaser] palatabflity,
but fatness appeared to have a greater
impact on the cuts from the rack and loin
than on the cuts from the leg.
Jeremiah et al. (1971) evaluated the im-
pact of chronological age and marbling on
the palatability of individual muscles from
leg steaks of lamb. Marbling appeared to
be of little consequence in determining the
tenderness of the rectus femoris, vastus
lateralis, biceps femoris, semitendinosus, or
semimembranosus muscles of the leg, but
chronological age was highly related to the
tenderness of these muscles. The authors
concluded that increased marbling was of
little importance for increasing the tender-
ness of leg muscles, but that increased
marbling was associates] with higher juici-
ness scores for the rectus femoris, vastus
lateralis, ant] semitendinosus muscles.
Smith et al. (1976) evaluated the influence
of fatness subcutaneous and marbling-on
the palatability of lamb. They found that
lamb carcasses that have increased quan-
tities of fat chid more slowly, maintain
muscle temperatures conducive to autolytic
enzyme degraclation for greater periods of
time postmortem, sustain less shortening of
sarcomeres, have muscles with lower ulti-
mate pH values, have less perceptible or
softer connective tissue, and are more tender
than lamb carcasses that have limited quan-
tities of subcutaneous or intramuscular fat.
The authors theorized that deposition of
increased quantities of subcutaneous or in-
tramuscular fat (particularly in carcasses
with limited quantities of subcutaneous fat)
increases tenderness by changing postmor-
tem chflling rate. Thus, an increased quan
APPENDIX
tity of fat decreases the rate of temperature
clecline, enhances the activity of autolytic
enzymes in muscle, lessens the extent of
myofibrfllar shortening, and thereby in-
creases the ultimate tenderness of cooked
meat from a fatter carcass.
Beef Palatability Research
Physical, Chemical, and Histological
Studies
Davis et al. (1979) investigated variations
in tenderness among beef steaks from car-
casses of the same USDA quality grade to
better understand why some steaks are less
palatable than others even when the USDA
quality grade is the same. For Choice, A
maturity beef loins, the most tender steaks
had more intramuscular fat, less intramus-
cular moisture, higher water-hol(ling capac-
ity, and a lower fragmentation index. Intra-
muscular fat percentages for steaks from the
four tenderness groups of Choice, A matu-
rity beef loins were as follows: very ten(ler
= 7.6 percent, moderately tender = 6.1
percent, slightly tender = 5.6 percent, and
slightly tough = 4.4 percent. For Choice,
B maturity beef loins, very tender steaks
had 7.2 percent fat while slightly tough
steaks had 5.6 percent fat. Although in the
other grade/maturity groups, other physical,
chemical, and histological factors were more
important than fatness, high tenderness scores
were most often associated with intramus-
cular fat percentages of 6 to 8.
Time-on-Feed and Beef Palatability
The length of time that cattle are fed
high-concentrate feeds is associated with
increased palatability, irrespective of quality
gracles. Tatum et al. (1980) reporter! that
rib steaks from high Choice ant] average
Choice carcasses were juicier, more flavor-
ful, and overall more palatable than steaks
from low Good/Select and high Standard
carcasses; however, steaks from low Choice,
OCR for page 349
ROLE OF FAT
high GoocI/Select, en c] average GoocI/Select
carcasses did not differ in palatability. In-
creased time-on-feed was associated with
increased carcass maturity, increased fat
deposition, clecreased yielcl grade, ant] in-
creased percentage of carcasses grading:
Choice. Increased feeding time from 100 to
160 days had a beneficial effect on flavor
desirability but die] not significantly affect
juiciness, tenderness, or overall palatability.
Tatum et al. (1980) suggester! that a knowl-
eclge of feeding history may be a useful
adjunct to-or substitute for-USDA qual-
ity grade for predicting beef palatability.
Dolezal et al. (1982a), in a stucly offeeding
groups of steers and heifers for periods
ranging from 30 to 230 clays, found that
extending feeding time beyond 90 to 100
days dill little to ensure additional palata-
bility. Within time-on-feecT strata from 100
through 230 days, few differences in palat-
ability were found between rib steaks from
carcasses of different USDA quality grades.
Dolezal et al. (1982a) recommended that
the minimum marbling requirement for the
Choice grade could be lowered with no
appreciable loss in palatability if it was
stipulated that cattle had been fed a high-
concentrate diet for at least 90 days.
Subcutaneous Fat Thickness and
Marbling
Several studies have been conducted that
explorer! the combined role of subcutaneous
fat ant] marbling in the palatability of beef.
Tatum et al. (1982) found that compared
with marbling, fat thickness was ineffective
as a predictor of cooked beef palatability
and, therefore, would appear to be an un-
suitable substitute for marbling. However,
marbling, user! in combination with a min-
imum subcutaneous fat thickness constraint
of 7.6 mm for carcasses with a Slight amount
of marbling, facilitated more equitable strat-
ification of carcasses according to their ex-
pected palatability than clid marbling alone.
Dolezal et al. (1982b) fount] that assigning
349
carcasses to three expected palatability groups
baser! on fat thickness was at least equivalent
to, and perhaps slightly more precise than,
the use of USDA quality gracles for grouping
the carcasses according to expected palata-
bilitY. There were progressive increases in
palatability of cooked beef as fat thickness
of carcasses increased from less than 2.5 to
7.6 mm, but quantities greater than 7.6 mm
die] not further improve palatability.
In studies involving young bulls, Riley et
al. (1983a,b) found that the combination of
subcutaneous fat and marbling was an im-
portant factor in the determination of beef
palatability. Subcutaneous fat thickness was
found to be more important than "mascu-
linity" in ensuring that beef from young
bulls would! be acceptably tender (Riley et
al., 1983a). Riley et al. (1983b) recom-
mendec! that the USDA grade standards for
beef could be revised to allow those car-
casses with Slight marbling and at least 7.6
mm of fat thickness to grade Choice, irre-
spective of sex. When steaks from Standard
bulls ant! steers and steaks from Good/Select
bulls and steers that hac] less than 7.6 mm
of fat thickness were compared with steaks
from Choice steers or steaks from Good/
Select bulls with at least 7.6 mm of fat
thickness, they were fount! to be signifi-
cantly less palatable (Riley et al., 1983b).
USDA Beef Quality Study
In the mid-1970s, the Texas Agricultural
Experiment Station conclucted a compre-
hensive study for the U.S. Department of
Agriculture on USDA beef quality grades
and palatability. This study involved 1,005
carcasses ranging in maturity from A to E
and in marbling from Moderately Abundant
to Practically Devoid. In their report on the
eject of maturity groups on palatability,
Smith et al. (1982) fount] that in comparison
to carcasses of B. C, or E maturity, carcasses
of A maturity pro(lucecl broiled steaks that
hail higher palatability ratings in 62 to 86
percent of comparisons, were decidedly less
OCR for page 350
350
variable in sensory traits, were more likely
to be assigned high (26.00) and less likely
to be assigned low (c2.99) sensory panel
ratings, and were more likely to have low
~ 3.63 kg) shear force values. They found
that position within the A or A + B maturity
groups explained 4 percent (loin steaks)
and 10 to 18 percent (round steaks) of the
observed variation in overall palatability
ratings and/or shear force values.
In the report on the relationship between
marbling and palatability, Smith et al. (1984)
fount! that as marbling increaser! from Prac-
tically Devoid to Moderately Abundant, loin
steaks were more palatable about two-thirds
of the time. round steaks were more nal
atable about one-eighth of the time, ant]
loin steaks were more likely to be assigned
high ~-6.00) panel ratings and to have low
~ 3.63) shear force values. However, in-
creases in marbling from Slight to Moder-
ately Abundant (A + B maturity) had little
or no effect on percentage incidence of loin
or round steaks with pane] ratings 2.99 or
24.00, or with shear force values 26.35 kg
or 4.99 kg. Differences in marbling ex-
plained about 33 percent (loin) and 7 percent
(top round) of the variation in overall pal-
atability ratings in A, B. C, and A + B
maturity carcasses.
Smith et al. s (1987) report on the influ-
ence of USDA quality gra(les on beef pal-
atability indicates] that Prime carcasses pro-
clucecl loin and round steaks that were more
palatable than the steaks from Choice through
Canner carcasses in 85.7 percent of com-
parisons and more palatable than the steaks
from Choice through Standard carcasses in
69.0 percent of comparisons. Comparable
percentages were 71.4 percent (for Choice
through Canner), 42.9 percent (for Choice
through Standard), 74.3 percent (for Goocl/
Select through Canner), and 35.7 percent
(for Good/Select compared to Standard).
Among Prime through Standard carcasses,
grade preclicted flavor, tenderness, ant]
overall palatability of loin steaks with 30 to
38 percent accuracy, but could only explain
APPENDIX
about 8 percent of the variation in sensory
pane} ratings or shear force values of round
steaks.
National Consumer Retail Beef Study
The National Consumer Retail Beef Study
was an industry-wide program supported
by government, producer, feecler, packer,
and retailer segments of the industry (Cross
et al., 1986~. The program was led by the
Texas Agricultural Experiment Station of
the Texas A&M University System with
coordination of the Beef Industry Council
of the National Live Stock & Meat Board
and the National Cattlemen s Association.
The beef industry identified two challenges
to achieving a market-(lriven orientation:
What are the demands of specific segments
of consumers, and what kinds of beef will
satisfy them?
The relationship between quality grade
and taste appeal was first addressed by
Savell et al. (1987~. The study (called Phase
I) was carrier] out in Philadelphia, Kansas
City, and San Francisco. Steaks from car-
casses that varier! in marbling were evalu-
ated by 540 households. For the first time,
a nationwide study was conclucted to see (1)
if consumers, rather than trained sensory
panelists, could detect differences in pal-
atability of steaks that (liffere~l in marbling
ant] t2) if there were regional consumer
preferences for steaks according to level of
marbling. Results showed that consumers
could detect palatability differences clue to
marbling ant] that there were indeed re-
gional differences with respect to the way
consumers rated steaks that differed in mar-
bling. Consumers in all three cities rated
steaks with high marbling the same. Con-
sumers in San Francisco and Kansas City
gave consistently high ratings that were only
slightly reduced as marbling decreased from
Slightly Abundant to Traces. But ratings
given by Philadelphia consumers were
sharply reduced as marbling decreased. Itus,
it appeared that different consumer market
OCR for page 351
ROLE OF FAT
segments might need to be identified to
more effectively reflect consumer tastes in
each city.
Because the information gatherer] in Phase
I acIdressed only one issue in the selection
of beef taste-specific demands for the
other major selection criteria price and
leanness remained unanswered. There-
fore, it became necessary to conduct Farther
research (Phase II) to determine (1) what
amount of taste, if any, would be sacrificed
by the consumer to obtain the leanness
advantages of lower gracling beef and (2)
what degree of external fat trim would
consumers seek ant] be willing to pay for.
Phase II of the National Consumer Retail
Beef Study (Cross et al., 1986; Swell et al.,
in press) was conducted in San Francisco
en cl Philadelphia (the two cities in Phase I
with the greatest clifference between con-
sumer ratings of steaks from the various
marbling levels). With respect to the mar-
bling or quality grade findings from Phase
II, retail cuts from Choice ant! Good/Select
carcasses were rated equally high for con-
sumer acceptance, but for different reasons.
Choice retail cuts were rated high in taste,
but when objections were voiced, they con-
cerned fatness. Good/Select retail cuts were
rated high in leanness, but when objections
were voiced, they concerned taste or tex-
ture. A major recommendation from this
study was to merchandise the two grades of
beef baser! on their strengths Choice should
be marketed for its taste appeal and Good/
Select for its leanness.
MINIMUM FAT IN MEAT NEEDED
FOR ACCEPTABLE PALATABILITY
Before a recommendation can be made
with respect to the level of fatness needecl
for acceptable palatability, it is important
to know how much chemical fat is present
in steaks from the various marbling levels.
Savell et al. (1986) reported the amount of
chemical fat in the uncookec! longissimus
dorsi muscle of 518 beef carcasses that
351
ranged in marbling from Moderately Abun-
dant to Practically Devoid (Figure 1~. Mean
values for chemical fat ranged from 10.42
percent in Moclerately Abundant to 1.77
percent in Practically Devoid. The authors
generated a regression equation to calculate
the amount of chemical fat in a raw loin
steak for known marbling level:
Percentage ether-extractable fat =
(Marbling score x 0.0217) - 0.8043.
For this equation (r2 = 0.78), marbling
score is converted to a numerical code where
Moderately Abundant = 800-899, Slightly
Abundant = 700-799, Moderate = 600-
699, Modest = 500-599, Small = 400-499,
Slight = 300-399, Traces = 200-299, and
Practically Devoid = 100-199. Using the
equation, the amounts of fat in Traces,
Slight, Small, Modest, ant! Moderate are
1.74, 3.00, 4.28, 5.55, and 6.82 percent,
respectively. These levels of fat are low
compared with the 10 to 50 percent levels
in processes! meat products.
The key question asked of us was, what
level of fatness is necessary for acceptable
palatability? After reviewing the research
we have concluctec] over the years under
many different circumstances and with many
different objectives, we conclude that the
minimum fat percentage required for ac-
ceptable palatability of broiling cuts (rib,
loin, sirloin, and so on) is 3 percent on an
uncooked basis (associated with the mini-
mum Slight degree of marbling). As in all
biological relationships, there is no magic
point where at one concentration or level
something is acceptable and at the next
increment it is not, but our findings are
basest on the overwhelming evidence of
many observations where steaks with less
than 3 percent animal fat (or the marbling
levels associated with less than 3 percent
fat Practically Devoid and Traces) are
tougher, drier, and less flavorful, whether
evaluated by trained panelists or by con-
sumers. Note that this is only a minimum
OCR for page 352
352
14
13
Ill 12
n 11
fit 10
~ 9
;5 8
s 7
Ill 6
-A 5
, 4
3
2
1
o
1
l
I I I I I I I I
MAB SLAB MD MT
SM SL TR PD
Marbling Score
FIGURE 1 Marbling score and ether extractable fat. NOTE: MAB is
moderately abundant; SLAB, slightly abundant; MD, moderate; MT,
modest; SM, small; SL, slight; TR, traces; and ED, practically devoid.
tat percentage tor ~~acceptable palatability;
it is our belief that there are two other
levels or plateaus of chemical fat associated
with increasing palatability: approximately
5 percent (midpoint of the Small amount of
marbling) and approximately 7 percent (the
lower end of the Moderate amount of mar-
bling). These hierarchical rankings in pal-
atability as associated with increasing fatness
allow the beef supply to be sorted into
expected palatability groups that can best
serve a segmented consumer market with
widely varying tastes.
The following discussion will help to fur-
ther defend our choice of 3 percent or Slight
marbling as the minimum level offal neecled
for acceptable palatability. Tatum et al.
(1982) found that marbling hack a low, but
positive, relationship to all the palatability
traits of beef, but that more than 90 percent
of the steaks with Slight or higher degrees
of marbling were desirable in tenderness,
flavor, and overall palatability. In unpub-
lished data generated by the USDA Beef
Quality Study, the relationship between
actual chemical fat levels and overall pal-
atability shows a distinct downturn in ratings
once fat is below 3 percent. The relationship
APPENDIX
between overall clesirability ratings and
marbling level for the three cities user! in
Phase I of the National Consumer Retail
Beef Study supports our contention that
once marbling drops below minimum Slight,
consumers are likely to find the meat less
palatable. Finally, in Phase II ofthe National
Consumer Retail Beef Stucly (Cross et al.,
1986; Savell et al., in press), although con-
sumers could detect differences in taste
between steaks ant] roasts from Choice and
Good/Select, they still rater] those from
Good/Select (Slight amount of marbling)
very high in overall acceptance primarily
because of the leanness and absence of waste
of the cuts.
Our recommendation of a minimum 3
percent fat is only for those cuts from the
rib and loin. Palatability evaluations of cuts
from the chuck and round fad] to show strong
relationships between fatness and palatabil-
ity. Griffin et al. (1985) fount] that consumers
could detect differences in palatability be-
tween steaks from the rib and loin of higher
grading steer carcasses when compares! with
steaks from lower grading bull carcasses,
but that they could not (letect differences
in palatability between roasts from the chuck
OCR for page 353
ROLE OF FAT
and round fiom the two groups. Smith et
al. (1984, 1987) reported that neither mar-
bling nor quality grade was closely associ-
ated with the sensory pane} ratings or shear
force values of steaks Dom the round. Over-
all palatability of the strip loin does reach a
point- at minimum Slight that the ratings
start to diminish quite drastically, but the
overall palatability ratings for the top round
are fairly level from Slightly Abundant to
Practically Devoid marbling. Therefore, it
is our opinion that in young cattle, there is
no minimum level of marbling or chemical
fat necessary to ensure acceptable palata-
bility for cuts from the round or chuck,
primarily because ofthe way they are cooked
(moist-heat roasting, braising, pan frying,
and so on) and because of lower consumer
expectation for these cuts compared with
higher parcel steaks from the rib and loin.
Although the data for minimum chemical
7r ~
-
~ 6
-
=
CIS
~ 5
o
4
353
fatness are not as well documented for pork
and lamb as they are for beef, because most
studies have focused their attention on the
relationship between general fatness of car-
casses and palatability, we still recommend
a minimum level of 3 percent chemical fat
for those cuts from the loin of pork and from
the loin and rack of lamb. Most of the
studies mentioned earlier in the sections on
pork and lamb found that there were certain
levels of fatness where undesirable chops
were encountered. Chemical fat is less im-
portant for palatability in the cuts from the
shoulder and leg of pork or lamb because
in pork they are further processed and in
lamb they are most often roasted, which
probably minimizes the influence of fat on
palatability. For lamb leg roasts, we rec-
ommend a minimum of 2 percent chemical
fat to ensure acceptable palatability.
Overall Palatabillty Strip Loin
0 Grams of Fat In Two Servings of Meat
L
so'
o'
I I I 1 1 ~I I I 1 1 1 1
1 2 3 4
5 6 7
Percent of Fat
22.5
17.5
_ 7.5
1 1 1 1 1 1 2.5
8 9
10 11
FIGURE 2 Window of acceptability for fat content of meat (palatability
versus grams of fat, two servings). The window is based on a fat content
range of 3 percent to 7.3 percent. This is equivalent to meat cuts that
grade in the lower range of Good/Select (3 to 4.27 percent fat content)
to those that grade in the high range of Choice (4.28 to 8.0 percent fat
content).
of
-
-
OCR for page 354
3s4
MAXIMUM FAT ALLOWABLE IN MEAT
FOR ACCEPTABLE NUTRITIONAL
MERIT
The point at which fat stops being an
asset (in terms of taste) and starts becoming
a liability (in terms of health) must also be
considerecI. We conclude that the maximum
amount of fat that should be present in cuts
of meat to ensure nutritional merit is 7.3
percent (uncooked basis). We arrived at this
figure based on the following assumptions:
· An intake of 2,000 kcal/clay;
· No more than 30 percent of calories
from fat, baser! on the American Heart
Association's Dietary Guidelines;
· Of the calories from fat, no more than
25 percent from fat in beef, pork, and lamb;
· No more than 600 kcal from fat ant] no
more than 150 kcal from fat from red meat;
· A maximum of 16.6 grams of fat from
red meat per clay;
· Two servings per day from the meat
group, based on good nutrition practice;
and 4 ounces, uncooked, per serving;
· 16.6 grams offal diviclec] by 226.8 grams
(number of grams in 8 ounces) = 7.3 percent
chemical fat in uncooked! portion.
Baser] on these calculations and our rec-
ommendations of 3 percent minimum fat,
Figure 2 was clevelopecl, which shows the
"window of acceptability" of fat in meat
products. This target is amply wide, since
it allows most cuts from carcasses that grade
low Good/Select to the middle of high
Choice to qualify. In a(lclition, smaller or
fewer servings of red meat per day would
accommodate a slightly higher fat level
without exceeding the American Heart As-
sociation's Dietary Guidelines. This "win-
clow" will cause some controversy from
those who are proponents of fat for taste
reasons (minimum level set too low) and
those who are opponents of fat for health
reasons (maximum level set too high), but
APPENDIX
we feel that these levels are very realistic
goals from both production and consump
tion points of view.
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OCR for page 356
Representative terms from entire chapter:
quality grade
