Beef Yield Grading S T U D E N T H A N D O U T. Accompanies: Meet Judging & Grading

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1 tep-wise Procedure for Yield Grading of Beef Carcasses Beef carcasses are divided into five yield (or cutability) grades. he term cutability refers to the percentage of carcass weight in boneless, closely trimmed retail cuts from the round, loin, rib and chuck. he following descriptions of carcasses in the yield grades may help you visualize these groups of carcasses. Yield Grade escriptions 1. Yield Grade 1 a. here is usually only a thin layer of external fat over the round, loin, rib and clod, along with slight deposits of fat in the flank, cod, udder, kidney, pelvic and heart regions. b. here is usually a very thin layer of fat over the outside of the round and over the clod. c. Muscles are usually visible through the fat in many areas of the carcass. 2. Yield Grade 2 a. he carcass is nearly completely covered with external fat, but the lean is very visible through the fat over the outside of the round, chuck and neck. b. here is usually a slightly thin layer of fat over the inside round, loin and rib, coupled with a slightly thick layer of fat over the rump, sirloin and clod. 3. Yield Grade 3 a. he carcass is usually completely covered with external fat, and the lean is plainly visible only through the fat on the lower part of the outside of the round and neck. b. here is usually a slightly thick layer of fat covering the inside round, loin and rib, plus a moderately thick layer of fat over the rump, sirloin and clod. c. here are usually slightly large deposits of fat in the flank, cod or udder, kidney, pelvic and heart regions. 4. Yield Grade 4 a. he carcass is usually completely covered with external fat, except muscle is visible in the shank, outside of the flank and plate regions. b. here is usually a moderately thick layer of external fat over the inside of the round, loin and rib, along with a thick layer of fat over the rump, sirloin and clod. c. here are usually large deposits of fat in the flank, cod or udder, kidney, pelvic and heart regions. 1

2 5. Yield Grade 5 a. he carcass generally has a thick layer of fat on all external regions. xtensive fat is found in the brisket, cod or udder, kidney, pelvic and heart regions. 2

3 RMIIG YIL GR o facilitate the determination of the yield grade (YG) to the nearest.10 unit for a given carcass, a meat judge should follow five basic steps. tep 1: etermine the Preliminary Yield Grade (PYG) a. stimate the fat thickness of the beef carcass at three-fourths of the distance across the ribeye from the backbone. b. change of.10 inch in fat thickness changes the PYG by.25 YG Fat over Ribeye PYG Fat over Ribeye PYG c. he PYG is often adjusted by graders. Perhaps 50 percent to 75 percent of all PYG measurements should be adjusted because the fat thickness measurement over the ribeye is not always an accurate index of the PYG of the entire carcass. wide variation exists in the outside fat distribution of beef carcasses. We will adjust the PYG of about one-third of all carcasses we grade. he maximum upward adjustment will be.40 PYG unit and the maximum downward adjustment will be.30 PYG unit. he criteria which we will use to adjust fat thickness includes fat at the rib-plate juncture, fat over the round and cod or udder fat. We will perfect this skill through practice. d. Record your adjusted PYG estimate as shown in tep five. s beef animals become heavier (especially beyond 1000 pounds in live weight or 600 pounds in carcass weight), they generally accumulate excessive amounts of external (subcutaneous) fat and seam fat (fat between the muscles). his is not true in all cases; nevertheless, the system for yield grading was designed for application to all carcasses. 3

4 tep 2: Carcass Weight to R djustment a. stimate the carcass muscling. stimation of expected cutability of beef carcasses must include a measure of muscling in addition to measures of fatness (fat thickness and percentage internal fat) and size (carcass weight). he area of the ribeye muscle at the interface of the 12 th rib is a valid index of carcass muscling, and can be measured using a ribeye dot grid or through visual estimation. b. he most challenging skill to master in meat judging is accurate estimation (within.3 square inch) of R. he relationship (100 pound carcass weight = 1.2 square inches) of carcass weight to ribeye area is outlined below. student estimates the difference between the actual size of the ribeye and the standard size of ribeye for its weight (i.e., the data shown below). he difference is then multiplied by three to determine the plus or minus R adjustment. n example is shown on page five. CRC WIG R CW (pounds) R CW (pounds) R

5 CRC WIG R JM Carcass R R R Weight eeded stimated djusted tep 3: djust for Percent KP deviations from a base of 3.5 percent Carcasses also accumulate various amounts of fat which protect certain vital organs. Fats surrounding the reproductive system in the pelvic cavity, kidneys in the abdominal cavity and heart in the thoracic cavity are routinely left in beef carcasses slaughtered in.. plants. hus, for accurate estimation of YG, the percentage of carcass weight represented by internal fats (kidney, pelvic, heart) must be estimated. Carcasses with greater than 3.5 percent kidney, pelvic and heart (KP) fat are penalized. Likewise, carcasses with less than 3.5 percent are credited, according to the official Beef Yield Grade tandards. a. change in KP of 1 percent alters the PYG by.20 YG KP fat, percent PYG djustment one b. KP estimate of 2.75 percent would require a -.15 PYG adjustment; 3.75 percent would require a +.05 PYG adjustment. c. ballpark figure for KP percentage of carcasses weighing 500 to 700 pound is 2.5 percent + 1 percent (in most cases); whereas the standard for carcasses weighing over 750 pound is percent. d. KP will range from about.5 percent to 5.5 percent 5

6 tep 4: Complete Procedure for etermining the Final Yield Grade a. evelop a chart with nine columns as show below. ote that: 1. PYG adjustment values can be cancelled to prevent arithmetic errors. 2. Lines divide the carcass data into groups of three to avoid recording errors. 3. ü appears after each FYG value to indicate addition and/or subtraction has been verified. JM PRLIMIRY YIL GR Carcass PYG R R R KP o. PYG adj. CW needed est. adj. adj. FYG ü ü ü ü ü ü b. With more practice, you will wish to use an easier table with five columns: Carcass dj. dj. dj. o. PYG R KP FYG c. his chart shows representative factors from each of the yield grades, so you can gain a better idea of what constitutes a typical carcass from that grade level. YPICL FCR FR CRC RPRIV F C YIL GR Factors Yield Fat Carcass a Grade thickness weight b R c KP ½ ½ ½ 6

7 a s YG increases in numeric value (decreased carcass cutability), carcasses generally increase in external fat thickness. b s YG increases in numerical value, carcasses generally increase in weight. c s YG increases in numerical value, carcasses generally decrease in R. ationally competitive collegiate yield graders completely master the mathematical portion of yield grading on paper prior to spending much time in the cooler practicing on specific carcasses. Following an understanding of the simple arithmetic adjustments, extensive practice on yield grading on at least 500 carcasses will develop a person s subjective evaluation skills to a competitive level. skilled meat grader also must learn how to consistently grade carcasses in different beef coolers varying widely in lighting, temperature, rail height, type of cattle and quality of dressing workmanship. ow it s time to put your pencil to the paper and see how well you understand the concepts you have read about and viewed. ry this grading exercise for practice. Good luck! Carcass Fat R R R KP o. K. PYG Wt. needed est. adj. KP adj FYG