designations. In previous grade standards for beef and in the standards for grades of other kinds of meat, the Department uses the term "quality" to refer only to the palatability-indicating characteristics of the lean without reference to conformation. Its use herein to include consideration of conformation is not intended to imply that variations in conformation are either directly or indirectly related to differences in palatability.

(b) The grade standards are written so that the quality and cutability standards are contained in separate sections. The quality section is divided further into three separate sections applicable to carcasses from (1) steers, heifers, and cows, (2) bulls, and (3) stags. There are five cutability groups applicable to all classes of beef, denoted by numbers 1 through 5, with cutability group 1 representing the highest degree of cutability. Eight quality designations-Prime, Choice, Good, Standard, Commercial, Utility, Cutter, and Canner-are applicable to steer, heifer and cow carcasses, except that cow carcasses are not eligible for Prime. The quality designations for bull and stag beef are Choice, Good, Commercial, Utility, Cutter, and Canner.

(c) The standards provide for the grading and stamping of beef from steers, heifers, and cows according to its characteristics as beef without sex identification. Such beef placed within each respective grade, therefore, shall possess the characteristics specified for that grade, irrespective of the sex of the animal from which it was derived. Beef produced from bulls and stags shall be graded according to its characteristics as bull beef or as stag beef in accordance with the standards. When graded and identified according to grade, such beef shall be identified also for class as "Bull" beef or "Stag" beef, as the case may be. The designated grades of bull beef or stag beef herein are not necessarily comparable in quality or cutability with a similarly designated grade of beef derived from steers, heifers, or cows. Neither is the quality or cutability in a designated grade of bull beef necessarily comparable with a similarly designated grade of stag beef.

(d) The Department uses photographs and other objective aids in the correct interpretation and application of the standards.

(e) To determine the quality or cutability of a carcass, it must be split down the back into two sides and one side must be partially separated into a hindquarter and forequarter by sawing and cutting it, insofar as practicable, as follows: A saw cut perpendicular to both the long axis and split surface of the vertebral column is made across the 12th thoracic vertebra at a point which leaves not more than one-half of this vertebra on the hindquarter. The knife cut across the ribeye muscle starts-or terminates-opposite the above-described saw cut. From that point it extends across the ribeye muscle perpendicular to the outside skin surface of the carcass at an angle toward the hindquarter which is slightly greater (more nearly horizontal) than the angle made by the 13th rib with the vertebral column of the hindquarter posterior to that point. As a result of this cut, the outer end of the cut surface of the ribeye muscle is closer to the 12th rib than is the end next to the chine bone. Beyond the ribeye, the knife cut shall continue between the 12th and 13th ribs to a point which will adequately expose the distribution of fat and lean in this area. The knife cut may be made prior to or following the saw cut but must be smooth and even, such as would result from a single stroke of a very sharp knife.

(f) Other methods of ribbing may prevent an accurate evaluation of grade determining characteristics. Therefore, carcasses ribbed by other methods will be eligible for grading only if an accurate grade determination is possible.

(g) Beveling of the fat over the ribeye, application of pressure, or any other influences which alter the area of the ribeye or the thickness of fat over the ribeye prevent an accurate cutability determination. Therefore, carcasses subjected to such influences may not be eligible for a cutability determination. Also carcasses with more than minor amounts of lean removed from the major sections of the round, loin, rib, or chuck will not be eligible for a cutability determination.

(h) The quality and cutability grade descriptions are defined primarily in terms of carcass beef. However, the quality standards also apply to the grading of hindquarters, forequarters, and individual primal cuts-rounds, loins, short loins, loin ends, ribs, and chucks. A portion of a primal cut as well as plates, flanks, shanks, and briskets likewise can be graded if attached by their natural

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attachments to a primal cut. Grade requirements for individual primal cuts or special cuts eligible for grading shall be based on the requirements specified in these standards and shall be consistent with the normal development of grade characteristics in various parts of a carcass of the quality level involved. The cutability standards also are applicable to the grading of hindquarters and forequarters, and to ribs, loins, short loins, and combinations of wholesale cuts which include either a rib or a short loin. Until such time as cutability standards are developed for rounds and chucks, their grade-when graded as a wholesale cut-will consist of the quality grade only. Other special major cuts or carcasses ribbed other than between the 12th and 13th ribs may be approved by the Consumer and Marketing Service for grading provided such deviations are necessary to meet either the demand of export trade or changing trade practices.

(i) Carcasses or wholesale cuts qualifying for any particular quality or cutability grade may vary with respect to their relative development of the various grade factors. There will be carcasses or wholesale cuts which qualify for a particular grade, some of whose characteristics may be more nearly typical of another grade. The following is an illustration of the foregoing. In comparison with the descriptions of maturity contained in the standards, a particular carcass might have a greater relative degree of ossification of the cartilages on the ends of its lumbar vertebrae than its other evidences of maturity. In such instances, the maturity of the carcass is not determined solely by the ossification of the lumbar vertebrae but neither is this ignored. All of the maturity-indicating factors are considered. In making any composite evaluation of two or more factors, it must be remembered that these frequently are developed to a different relative extent. Because it is impractical to describe the nearly limitless number of such recognizable combinations of characteristics, the standards for each quality and cutability grade describe only beef which has a relatively similar degree of development of the various factors affecting its quality and cutability. Also, the quality and cutability standards each describe beef which is representative of the lower limits of each quality and cutability group.

(j) The quality grade of a beef carcass Jis based on separate evaluations of two

general considerations: (1) The quality or the palatability-indicating characteristics of the lean and (2) the conformation of the carcass.

(k) Conformation is the manner of formation of the carcass or primal cut. The conformation descriptions included in each of the grade specifications refer to the thickness of muscling and to an overall degree of thickness and fullness of the carcass and its various parts. Carcasses or primal cuts which meet the requirements for thickness of muscling specified for a grade will be considered to have conformation adequate for that grade despite the fact that, because of a lack of fatness, they may not have the overall degree of thickness and fullness described.

(1) Conformation is evaluated by averaging the conformation of the various parts of the carcass or primal cut, considering not only the proportion that each part is of the carcass or primal cut weight but also the general value of each part as compared with the other parts. Thus, although the chuck and round are nearly the same percentage of the carcass weight, the round is considered the more valuable cut. Therefore, in evaluating the overall conformation of a carcass, the development of the round is given more consideration than the development of the chuck. Similarly, since the loin is both a greater percentage of the carcass weight and also generally a more valuable cut than the rib, its conformation receives much more consideration than the conformation of the rib. Superior conformation implies a high proportion of meat to bone and a high proportion of the weight of the carcass or cut in the more valuable parts. It is reflected in carcasses and cuts which are very thickly muscled, very full and thick in relation to their length and which have a very plump, full, and wellrounded appearance. Inferior conformation implies a low proportion of meat to bone and a low proportion of the weight of the carcass or cut in the more valuable parts. It is reflected in carcasses and cuts which are very thinly muscled, very narrow and thin in relation to their length and which have a very angular, thin, sunken appearance.

(m) Quality of the lean is evaluated by considering its marbling and firmness as observed in a cut surface in relation to the apparent maturity of the animal from which the carcass was produced,

The maturity of the carcass is determined by evaluating the size, shape, and ossification of the bones and cartilagesespecially the split chine bones-and the color and texture of the lean flesh. In the split chine bones, ossification changes occur at an earlier stage of maturity in the posterior portion of the vertebral column (sacral vertebrae) and at progressively later stages of maturity in the lumbar and thoracic vertebrae. The ossification changes that occur in the cartilages on the ends of the split thoracic vertebrae are especially useful in evaluating maturity and these vertebrae are referred to frequently in the standards. Unless otherwise specified in the standards, whenever the ossification of cartilages on the thoracic vertebrae is referred to, this shall be construed to refer to the cartilages attached to the thoracic vertebrae at the posterior end of the forequarter. The size and shape of the rib bones also are important considerations in evaluating differences in maturity. In the very youngest carcasses considered as "beef," the cartilages on the ends of the chine bones show no ossification, cartilage is evident on all the vertebrae of the spinal column, and the sacral vertebrae show distinct separation. In addition, the split vertebrae usually are soft and porous and very red in color. In such carcasses the rib bones have only a slight tendency toward flatness. In progressively more mature carcasses, ossification changes become evident first in the bones and cartilages of the sacral vertebrae, then in the lumbar vertebrae, and still later in the thoracic vertebrae. In beef which is very advanced in maturity, all the split vertebrae will be devoid of red color, very hard and flinty, and the cartilages on the ends of all the vertebrae will be entirely ossified. Likewise, with advancing maturity, the rib bones will become progressively wider and flatter until in beef from very mature animals the ribs will be very wide and flat.

(n) The color and texture of the lean flesh also undergo progressive changes with advancing maturity. In the very youngest carcasses considered as "beef," the lean flesh will be very fine in texture and light grayish red in color. In progressively more mature carcasses, the texture of the lean will become progressively coarser and the color of the lean will become progressively darker red. In very mature beef the lean flesh will be very coarse in texture and very dark red

in color. Since color of lean also affected by variations in quality, refe ences to color of lean in the standar for a given degree of maturity va slightly with different levels of qualit In determining the maturity of a carca or cut in which the skeletal evidenc of maturity are different from those il dicated by the color and texture of t lean, slightly more emphasis is plac on the characteristics of the bones a cartilages than on the characteristics the lean. In no case can the overall m turity of the carcass or cut be consider more than one full maturity group diffe ent from that indicated by its bones a cartilages.

(0) In determining compliance wi the maximum maturity limits for t Prime, Choice, Good, and Standa grades, color and texture of the lean a considered only when the maturit indicating factors other than color a texture of the lean indicates only slightly more advanced degree of m turity than that specified as maximu for the applicable grade, and provid further that the lean is considerat finer in texture and lighter in color th normal for the grade and maturity i volved. The same principle, in rever is likewise applicable to determini compliance with the minimum maturi limits of the Commercial grade.

(p) These standards are applicable the grading of beef within the full ran of maturity within which cattle are ma keted. However, the range of maturi permitted within each of the grad varies considerably. The Prime, Choi Good, and Standard grades are restrict to beef from young cattle; the Comme cial grade is restricted to beef from cat too mature for Good or Standard; a the Utility, Cutter, and Canner grad include beef from animals of all age Within any specified grade, the requir ments for marbling and firmness i crease progressively with evidences advancing maturity. To facilitate t application of this principle, the stan ards recognize nine different degrees marbling and five different maturi groupings.

(q) The relationship between ma bling, maturity, and quality (that part the final grade that represents the pala ability of the lean) is shown in Figure From this figure it can be seen, for i stance, that the minimum marbling r quirement for Choice varies from minimum small amount for the ve

*Maturity increases from left to right (A through E) Represents midpoint of Prime and Commercial grades.

youngest carcasses classified as beef to a maximum modest amount for carcasses having the maximum maturity permitted in Choice. Likewise, in the Commercial grade the minimum marbling requirement varies from a minimum small amount in beef from animals with the minimum maturity permitted to a maximum moderate amount in beef from very mature animals. Illustrations of the lower limits of eight of the nine degrees of marbling considered in grading beef are available from the Department of Agriculture. No consideration is given to marbling beyond that considered "maximum abundant." The marbling and other lean flesh characteristics specified for the various grades are based on their appearance in the ribeye muscle of properly chilled carcasses that are ribbed between the 12th and 13th ribs. (r) The final quality grade of a carcass or primal cut is based on a composite evaluation of its conformation and quality.

Since relatively few carcasses or cuts have an identical development of conformation and quality, it is obvious that each grade will include various combinations of development of these two characteristics. Examples of how conformation and quality are combined into the final quality grade are included in each of the grade descriptions. The principles governing these compensations are as follows: In each of the grades a superior development of quality is permitted to compensate for a deficient development of conformation, without limit, through the upper limit of quality. The rate of compensation in all grades is on an equal basis—a given degree of superior quality compensates for the same degree of deficient conformation. The reverse type of compensation-a superior development of conformation for an inferior development of quality-is not permitted in the Prime, Choice, and Commercial grades. In all other grades this type of compensation is permitted but only to the extent of one-third of a grade of deficient quality. The rate of compensation is also on an equal basisa given degree of superior conformation compensates for the same degree of deficient quality.

(s) References to color of lean in the standards involve only colors associated with changes in maturity. They are not intended to apply to colors of lean associated with so-called "dark cutting beef". Dark cutting beef is believed to be the result of a reduced sugar content

of the lean at the time of slaughter. As a result, this condition does not have the same significance in grading as do the darker shades of red associated with advancing maturity. The dark color of the lean associated with "dark cutting beef" is present in varying degrees from that which is barely evident to so-called "black cutters" in which the lean is actually nearly black in color and usually has a "gummy" texture. Although there is little or no evidence which indicates that the "dark cutting" condition has any adverse effect on palatability, it is considered in grading because of its effect on acceptability and value. Dependent upon the degree to which this characteristic is developed, the final grade of carcasses which otherwise would qualify for the Prime, Choice, or Good grades may be reduced as much as one full grade. In beef otherwise eligible for the Standard or Commercial grade, the final grade may be reduced as much as one-half of a grade. In the Utility, Cutter, and Canner grades, this condition is not considered.

(t) The cutability group of a beef carcass is determined by considering four characteristics: (1) The amount of external fat, (2) the amount of kidney, pelvic, and heart fat, (3) the area of the ribeye muscle, and (4) the carcass weight.

(u) The amount of external fat on a carcass is evaluated in terms of the thickness of this fat over the ribeye muscle measured perpendicular to the outside surface at a point three-fourths of the length of the ribeye from its chine bone end. This measurement may be adjusted, as necessary, to reflect unusual amounts of fat on other parts of the carcass. In determining the amount of this adjustment, if any, particular attention is given to the amount of fat in such areas as the brisket, plate, flank, cod or udder, inside round, rump, and hips in relation to the actual thickness of fat over the ribeye. Thus, in a carcass which is fatter over other areas than is indicated by the fat measurement over the ribeye, the measurement is adjusted upward. Conversely, in a carcass which has less fat over the other areas than is indicated by the fat measurement over the ribeye, the measurement is adjusted downward. In many carcasses no such adjustment is necessary; however, an adjustment in the thickness of fat measurement of one-tenth or two-tenths of an inch is not uncommon. In some car