trations of carcasses which are near the borderlines between groups. For example, the characteristics listed for cutability group 1 represent carcasses which are near the borderline of cutability groups 1 and 2. These descriptions facilitate the subjective determination of the cutability group without making detailed measurements and computations. The cutability group for most beef carcasses can be determined accurately on the basis of a visual appraisal.

[30 F.R. 4456, Apr. 7, 1965]

§ 53.103 Specifications for official United States standards for grades of carcass beef (cutability).

(a) The cutability group of a beef carcass is determined on the basis of the following equation: Cutability group2.50+(2.50 x adjusted fat thickness, inches) + (0.20 x percent kidney, pelvic, and heart fat)+(0.0038 x hot carcass weight, pounds)-(0.32 x area ribeye, square inches).

(b) (1) The cutability group of a hindquarter, forequarter, or cut eligible for grading also is determined on the basis of the above equation in which the hot carcass weight is determined by multiplying the chilled weight of the cut by an appropriate factor as applicable to the cut and its style of preparation.

(2) The factors shown below shall be applicable to hindquarters and forequarters produced by ribbing as described herein, and to ribs, trimmed full loins, and trimmed short loins which are trimmed as described in Items 103, 172, and 173, respectively, of the Institutional Meat Purchase (IMP) Specifications for Fresh Beef-Series 100, as revised October 1961.

(5) For untrimmed hindquarters and for untrimmed hindquarter cuts, the quantity of kidney and pelvic fat is estimated as a percent of the hot side weight.

(c) The following descriptions provide a guide to the characteristics of carcasses in each cutability group to aid in determining cutability groups subjectively.

(1) Cutability Group 1. (i) A carcass in cutability group 1 usually has only a thin layer of external fat over the ribs, loins, rumps, and clods and slight deposits of fat in the flanks and cod or udder. There is usually a very thin layer of fat over the outside of the rounds and over the tops of the shoulders and necks. Muscles are usually visible through the fat in many areas of the

carcass.

(ii) A 500-pound carcass of this group which is near the borderline of cutability groups 1 and 2 might have three-tenths inch of fat over the ribeye, 11.5 square inches of ribeye, and 2.5 percent of its weight in kidney, pelvic, and heart fat.

(iii) An 800-pound carcass of this group which is near the borderline of cutability groups 1 and 2 might have four-tenths inch of fat over the ribeye, 16.0 square inches of ribeye, and 2.5 percent of its weight in kidney, pelvic, and heart fat.

(2) Cutability Group 2. (1) A carcass in cutability group 2 usually is nearly completely covered with fat but the lean is plainly visible through the fat over the outside of the rounds, the tops of shoulders, and the necks. There usually is a slightly thin layer of fat over the

loins, ribs, and inside rounds and the fat over the rumps, hips, and clods usually is slightly thick. There are usually small deposits of fat in the flanks and cod or udder.

(ii) A 500-pound carcass of this group which is near the borderline of cutability groups 2 and 3 might have five-tenths inch of fat over the ribeye, 10.5 square inches of ribeye, and 3.5 percent of its weight in kidney, pelvic, and heart fat.

(iii) An 800-pound carcass of this group which is near the borderline of cutability groups 2 and 3 might have six-tenths inch of fat over the ribeye, 15.0 square inches of ribeye, and 3.5 percent of its weight in kidney, pelvic, and heart fat.

(3) Cutability Group 3. (i) A carcass in cutability group 3 usually is completely covered with fat and the lean usually is visible through the fat only on the necks and the lower part of the outside of the rounds. There usually is a slightly thick layer of fat over the loins, ribs, and inside rounds and the fat over the rumps, hips, and clods usually is moderately thick. There usually are slightly large deposits of fat in the flanks and cod or udder.

(ii) A 500-pound carcass of this group which is near the borderline of cutability groups 3 and 4 might have seven-tenths inch of fat over the ribeye, 9.5 square inches of ribeye, and 4.0 percent of its weight in kidney, pelvic, and heart fat.

(iii) An 800-pound carcass of this group which is near the borderline of cutability groups 3 and 4 might have eight-tenths inch of fat over the ribeye, 14.0 square inches of ribeye, and 4.5 percent of its weight in kidney, pelvic, and heart fat.

(4) Cutability Group 4. (i) A carcass in cutability group 4 usually is completely covered with fat. The only muscles usually visible are those on the shanks and over the outside of the plates and flanks. There usually is a moderately thick layer of fat over the loins, ribs, and inside rounds and the fat over the rumps, hips, and clods usually is thick. There usually are large deposits of fat in the flanks and cod or udder. (ii) A 500-pound carcass of this group which is near the borderline of cutability groups 4 and 5 might have one inch of fat over the ribeye, 9.0 square inches of ribeye, and 4.5 percent of its carcass

weight in kidney, pelvic, and heart fat.

(iii) A 800-pound carcass of this group which is near the borderline of cutability groups 4 and 5 might have one and one-tenth inch of fat over the ribeye, 13.5 square inches of ribeye, and 5.0 percent of its weight in kidney, pelvic, and heart fat.

(5) Cutability Group 5. A carcass in cutability group 5 usually has more fat on all of the various parts, a smaller area of ribeye, and more kidney, pelvic, and heart fat than a carcass in cutability group 4.

[30 F.R. 4459, Apr. 7, 1965]

§ 53.104

Specifications for official United States standards for grades of carcass beef (quality-steer, heifer, cow).

(a) Prime. (1) Carcasses and wholesale cuts with minimum Prime grade conformation are thickly muscled throughout and tend to be very wide and thick in relation to their length. Loins and ribs tend to be thick and full. Rounds tend to be plump and the plumpness carries well down to the hocks. The chucks tend to be thick and the necks and shanks tend to be short.

(2) (i) Minimum quality characteristics are described for two maturity groups which cover the entire range of maturity permitted in the Prime grade.

(ii) Carcasses in the younger group range from the youngest that are eligible for the beef class to those at the juncture of the two maturity groups, which have slightly red and slightly soft chine bones and cartilages on the ends of the thoracic vertebrae that have some evidence of ossification. In addition, the sacral vertebrae are completely fused and the cartilages on the ends of the lumbar vertebrae are nearly completely ossified. The rib bones are slightly wide and slightly flat and the ribeye muscle is light red in color and is fine in texture. The minimum degree of degree of marbling required increases with advancing maturity throughout this group from minimum slightly abundant to maximum slightly abundant (see Figure 1) and the ribeye muscle is moderately firm.

(iii) Carcasses in the older group range from those described above as representative of the juncture of the two groups to those at the maximum maturity permitted in the Prime grade,

which have chine bones tinged with red and cartilages on the ends of the thoracic vertebrae that are partially ossified. In addition, the cut surface of the lean tends to be fine in texture and the carcasses are at least moderately symmetrical and uniform in contour. The minimum degree of marbling required increases with advancing maturity

throughout this group from minimum moderately abundant to maximum moderately abundant (see Figure 1) and the ribeye muscle is firm.

(3) A development of quality superior to that specified as minimum for the Prime grade may compensate, without limit, for a development of conformation inferior to that specified as minimum for Prime at an equal rate as indicated in the following example: A carcass which has mid-point Prime quality may have conformation equal to the mid-point of the Choice grade and remain eligible for Prime. However, regardless of the extent to which the conformation of a carcass exceeds the minimum of the grade, a carcass must have minimum Prime quality to be eligible for Prime.

(4) Only beef produced from steers and heifers is eligible for the Prime grade.

(b) Choice. (1) Carcasses and wholesale cuts with minimum Choice grade conformation are moderately thick muscled throughout and tend to be moderately wide and thick in relation to their length. Loins and ribs tend to be moderately thick and full. Rounds tend to be moderately plump. The chucks tend to be moderately thick and the necks and shanks tend to be moderately short.

(2) (1) Minimum quality characteristics are described for two maturity groups which cover the entire range of maturity permitted in the Choice grade.

(ii) Carcasses in the younger group range from the youngest that are eligible for the beef class to those at the juncture of the two maturity groups, which have slightly red and slightly soft chine bones and cartilages on the ends of the thoracic vertebrae that have some evidence of ossification. In addition, the sacral vertebrae are completely fused and the cartilages on the ends of the lumbar vertebrae are nearly completely ossified. The rib bones are slightly wide and slightly flat and the ribeye muscle is moderately light red in color and is fine in texture.

The minimum degree of marbling required increases with advancing maturity throughout this group from a minimum small amount to a maximum small amount (see Figure 1) and the ribeye muscle is slightly soft.

(iii) Carcasses in the older group range from those described above as representative of the juncture of the two groups to those at the maximum maturity permitted in the Choice grade, which have chine bones tinged with red and cartilages on the ends of the thoracic vertebrae that are partially ossified. In addition, the cut surface of the lean tends to be fine in texture and the carcasses are at least moderately symmetrical and uniform in contour. The minimum degree of marbling required increases with advancing maturity throughout this group from a minimum modest amount to a maximum modest amount (see Figure 1) and the ribeye muscle is slightly firm.

(3) A development of quality superior to that specified as minimum for the Choice grade may compensate, without limit, for a development of conformation inferior to that specified as minimum for Choice at an equal rate as indicated in the following example: A carcass which has mid-point Choice quality may have conformation equal to the mid-point of the Good grade and remain eligible for Choice. However, regardless of the extent to which the conformation of a carcass exceeds the minimum of the grade, a carcass must have minimum Choice quality to be eligible for Choice.

(c) Good. (1) Carcasses and wholesale cuts with minimum Good grade conformation are slightly thick muscled throughout and tend to be slightly wide and thick in relation to their length. Loins and ribs tend to be slightly thick and full. Rounds tend to be slightly plump, and necks and shanks tend to be slightly long and thin.

(2) (1) Minimum quality characteristics are described for two maturity groups which cover the entire range of maturity permitted in the Good grade.

(ii) Carcasses in the younger group range from the youngest that are eligible for the beef class to those at the juncture of the two maturity groups, which have slightly red and slightly soft chine bones and cartilages on the ends of the thoracic vertebrae that have some evi

dence of ossification. In addition, the sacral vertebrae are completely fused and the cartilages on the ends of the lumbar vertebrae are nearly completely ossified. The rib bones are slightly wide and slightly flat and the ribeye muscle is slightly light red in color and is fine in texture. The minimum degree of marbling required increases with advancing maturity throughout this group from typical traces to a typical slight amount (see Figure 1) and the ribeye muscle is moderately soft.

(iii) Carcasses in the older group range from those described above as representative of the juncture of the two groups to those at the maximum maturity permitted in the Good grade, which have chine bones tinged with red and cartilages on the ends of the thoracic vertebrae that are moderately ossified. In addition, the cut surface of the lean is moderately fine in texture and the carcasses are at least moderately symmetrical and uniform in contour. The minimum degree of marbling required increases with advancing maturity throughout this group from a typical slight amount to a maximum small amount (see Figure 1) and the ribeye muscle is slightly soft.

(3) A development of quality superior to that specified as minimum for the Good grade may compensate, without limit, for a development of conformation inferior to that specified as minimum for Good at an equal rate as indicated in the following example: A carcass which has mid-point Good grade quality may have conformation equivalent to the mid-point of the Standard grade and remain eligible for Good. Also, a carcass which has at least one-third of a grade superior conformation to that specified as minimum for the grade may qualify for Good with a development of quality equivalent to the lower limit of the upper third of the Standard grade. Compensation of superior conformation for inferior quality is limited to one-third of a quality grade.

(d) Standard. (1) Carcasses and wholesale cuts with minimum Standard grade conformation tend to be thinly muscled throughout and are slightly narrow and thin in relation to their and slightly thin fleshed. The rounds length. Loins and ribs tend to be flat tend to be thin and slightly concave.

Chucks tend to be flat and thin fleshed.

(2)(i) Minimum quality characteristics are described for two maturity groups which cover the entire range of maturity permitted in the Standard grade.

(ii) Carcasses in the younger group range from the youngest that are eligible for the beef class to those at the juncture of the two maturity groups, which have slightly red and slightly soft chine bones and cartilages on the ends of the thoracic vertebrae that have some evidence of ossification. In addition, the sacral vertebrae are completely fused and the cartilages on the ends of the lumbar vertebrae are nearly completely ossified. The rib bones are slightly wide and slightly flat and the ribeye muscle is slightly dark red in color and is fine in texture. The minimum degree of marbling required increases with advancing maturity throughout this group from minimum practically devoid to maximum practically devoid (see Figure 1) and the ribeye muscle is soft.

(iii) Carcasses in the older group range from those described above as representative of the juncture of the two groups to those at the maximum maturity permitted in the Standard grade, which have chine bones tinged with red and cartilages on the ends of the thoracic vertebrae that are moderately ossified. In addition, the cut surface of the lean is moderately fine in texture and the carcasses are at least moderately symmetrical and uniform in contour. The minimum degree of marbling required increases with advancing maturity throughout this group from minimum traces to a typical slight amount (see Figure 1) and the ribeye muscle is moderately soft.

(3) A development of quality superior to that specified as minimum for the Standard grade may compensate, without limit, for a development of conformation inferior to that specified as minimum for Standard at an equal rate as indicated in the following example: A carcass which has mid-point Standard quality may have conformation equal to the midpoint of the Utility grade and remain eligible for Standard. Also, a carcass which has at least one-third of a grade superior conformation to that specified as minimum for the grade may qualify for Standard with a development of

quality equal to the minimum of the upper third of the Utility grade. Compensation of superior conformation for inferior quality is limited to one-third of a quality grade

Commercial

(e) Commercial. (1) grade beef carcasses and wholesale cuts are restricted to those with evidences of more advanced maturity than permitted in the Good and Standard grades. Carcasses and wholesale cuts with minimum Commercial grade conformation are slightly thin muscled throughout. However, because of the usually moderately heavy fat covering the carcasses tend to be slightly thick but rather rough and irregular in contour. Rounds tend to be thin and slightly concave. Loins tend to be moderately wide but slightly sunken and the hips are rather prominent. Ribs tend to be slightly thick and full. Chucks are slightly thin and the plates and briskets are wide and "spready." The necks and shanks are slightly long and thin.

(2) (i) Three maturity groups are recognized in the Commercial grade. Minimum quality characteristics are described for the youngest and the most mature of these groups. The requirements for the intermediate group are determined by interpolation between the requirements indicated for the two groups described.

(ii) Carcasses in the youngest group permitted in the Commercial grade range from those with indications of maturity barely more advanced than described as maximum for the Good and Standard grades to those with moderately hard, rather white chine bones and with cartilages on the ends of the thoracic vertebrae that show considerable ossification but the outlines of the cartilages are still plainly visible. In addition, the rib bones are moderately wide and flat and the ribeye muscle is moderately dark red and slightly coarse in texture. The minimum degree of marbling required increases with advancing maturity throughout this group from a minimum small amount to a maximum small amount (see Figure 1) and the ribeye muscle is slightly firm.

(iii) The youngest carcasses in the most mature group included in the Commercial grade have hard, white chine bones and the outlines of the cartilages on the ends of the thoracic vertebrae

are barely visible, the rib bones are wide and flat, and the ribeye muscle is dark red and coarse in texture. The range in maturity in this group extends to include carcasses from the oldest animals marketed. The minimum degree of marbling required increases with advancing maturity throughout this group from a minimum moderate amount to a maximum moderate amount (see Figure 1) and the ribeye muscle is firm.

(3) A development of quality superior to that specified as minimum for the Commercial grade may compensate, without limit, for a development of conformation inferior to that specified as minimum for Commercial at an equal rate as indicated in the following example: A carcass which has mid-point Commercial quality may have conformation equal to the mid-point of the Utility grade and remain eligible for Commercial. However, regardless of the extent to which the conformation of a carcass exceeds the minimum of the Commercial grade, the carcass must have quality to the minimum of the Commercial grade to be eligible for Commercial.

(f) Utility. (1) Carcasses and wholesale cuts with minimum Utility grade conformation are thinly muscled throughout and are very narrow in relation to their length. They are decidely rangy, angular, and irregular in contour, and are usually thinly fleshed. The loins and ribs are flat and thinly fleshed. The rounds tend to be very thin and concave. The chucks are thin and flat. The necks and shanks are long and tapering. The hips and shoulder joints are prominent.

(2) (i) Carcasses within the full range of maturity classified as beef are included in the Utility grade. Thus, five maturity groups are recognized. Minimum quality requirements are described for three of these groups-the first or youngest, the third or intermediate, and the fifth or the most mature. The requirements for the second and fourth maturity groups are determined by interpolation between the requirements described for their adjoining groups.

(ii) Carcasses in the first or youngest maturity group range from the youngest that are eligible for the beef class to those at the juncture of the first two maturity groups, which have slightly red