Pork Carcass Grades and Standards

Grades of Barrow and Gilt Carcass
  1. U.S. No. 1
a.Barrow and gilt carcasses in this grade have an acceptable quality of lean and belly thickness and a high expected yield (60.4 percent and over) of four lean cuts. U.S. No. 1 barrow and gilt carcasses must have less than average backfat thickness over the last rib with average muscling, or average backfat thickness over the last rib coupled with thick muscling. 
b. Barrow and gilt carcasses with average muscling will be graded U.S. No. 1 if their backfat thickness over the last rib is less than 1.00 inch. Carcasses with thick muscling will be graded U.S. No. 1 if their backfat thickness over the last rib is less than 1.25 inches. Carcasses with thin muscling may not be graded U.S. No. 1. 
  1. U.S. No. 2. 
a. Barrow and gilt carcasses in this grade have an acceptable quality of leanand belly thickness and an average expected yield (57.4 to 60.3 percent) of four lean cuts. Carcasses with average backfat thickness over the last rib and average muscling, less than average backfat thickness over the last rib and thin muscling, or greater than average backfat thickness over the last rib and thick muscling will qualify for this grade.
b. Barrow and gilt carcasses with average muscling will be graded U.S. No. 2 if their backfat thickness over the last rib is 1.00 to 1.24 inches. Carcasses with thick muscling will be graded U.S. No. 2 if their backfat thickness over the last rib is 1.25 to 1.49 inches. Carcasses with thin muscling must have less than 1.00 inch of backfat thickness over the last rib to be graded U.S. No. 2.
  1. U.S. No. 3.
a. (i) Barrow and gilt carcasses in this grade have an acceptable quality of lean and belly thickness and a slightly low expected yield (54.4 to 57.3 percent) of four lean cuts. Carcasses with average muscling and more than average backfat thickness over the last rib, thin 6 muscling and average backfat thickness over the last rib, or thick muscling and much greater than average backfat thickness over the last rib will qualify for this grade.
b. Barrow and gilt carcasses with average muscling will be graded U.S. No. 3 if their backfat thickness over the last rib is 1.25 to 1.49 inches. Carcasses with thick muscling will be graded U.S. No. 3 if their backfat thickness over the last rib is 1.50 to 1.74 inches. Carcasses with 1.75 inches or greater backfat thickness over the last rib cannot grade U.S. No. 3. Carcasses with thin muscling will be graded U.S. No. 3 if their backfat thickness over the last rib is 1.00 to 1.24 inches.
  1. U.S. No. 4. 
a. Barrow and gilt carcasses in this grade have an acceptable quality of lean and belly thickness and a low expected yield (less than 54.4 percent) of four lean cuts. Carcasses in the U.S. No. 4 grade always have more than average backfat thickness over the last rib, and thick, average, or thin muscling, depending on the degree to which the backfat thickness over the last rib exceeds the average.
b. Barrow and gilt carcasses with average muscling will be graded U.S. No. 4 if their backfat thickness over the last rib is 1.50 inches or greater. Carcasses with thick muscling will be graded U.S. No. 4 with backfat thickness over the last rib of 1.75 inches or greater, and those with thin muscling will be graded U.S. No. 4 with 1.25 inches or greater backfat thickness over the last rib.
  1. U.S. Utility. All carcasses with unacceptable quality of lean or belly thickness will be graded U.S. Utility, regardless of their degree of muscling or backfat thickness over the last rib. Also, all carcasses which have soft and/or oily fat will be graded U.S. Utility.
 
Grades of Sow Carcasses
  1. U.S. No. 1 grade sow carcasses have about the minimum degree of finish required to produce pork cuts of acceptable palatability. Meatiness and yield of lean cuts from carcass weight are slightly high. Yield of fat cuts is slightly low. The ratio of total lean and fat to bone is slightly high. Carcasses with the minimum finish required for U.S. No. 1 grade are moderately long and slightly wide in relation to weight. The back and loins are moderately full and thick with a well-rounded appearance. Hams are usually moderately thick and plump and are slightly full in the lower part toward the hock. Bellies are moderately long, slightly thick, and moderately uniform in thickness with a slightly thick belly pocket. Shoulders are slightly thick and full. Carcasses are usually moderately well-balanced and moderately uniform in fleshing and finish. There are moderate quantities of interior fat in the pelvic area, a slightly thin but moderately extensive layer of fat lining the inside surface of the ribs, and a slightly small quantity of feathering, or fat intermingled with the lean between the ribs. The lean is firm. Both exterior and interior fats are firm, white, and of excellent quality. Carcasses with back fat thickness qualifying them for the fatter one-half of the U.S. No. 1 grade but with thin muscling in the major cuts, uneven fleshing and finish, or thick and uneven bellies shall be graded U.S. No. 2. Carcasses with back fat thickness qualifying them for the thinner one-half of the U.S. No. 1 grade but with only a moderately thin and incomplete rib lining, a moderately small quantity of feathering, slightly thin bellies with moderately thin belly pockets, and moderately soft lean and fat shall be graded Medium.
  2. U.S. No. 2 grade sow carcasses have a higher degree of finish than the minimum required to produce pork cuts of acceptable palatability. Meatiness and yield of lean cuts from carcass weight are slightly low. Yield of fat cuts is slightly high. The ratio of total lean and fat to bone is moderately high. Carcasses with the minimum finish required for U.S. No. 2 grade are slightly short and moderately wide in relation to weight. The back and loins are full and thick and are especially full near the edges. Hams are usually thick and plump and are moderately full in the lower part toward the hock. Bellies are slightly short, moderately thick, and rather uniform in thickness with a moderately thick belly pocket. Shoulders are moderately thick and full. Carcasses are usually well-balanced and uniform in fleshing and finish. There are slightly large quantities of interior fat in the pelvic area, a slightly thick and rather extensive layer of fat lining the inside surface of the ribs, and moderate feathering. The lean is firm. Both exterior and interior fats are firm, white, and of excellent quality. Carcasses with back fat thickness qualifying them for the fatter one-half of the U.S. No. 2 grade but with thin muscling in the major cuts uneven fleshing and finish, or very thick and uneven bellies shall be graded U.S. No. 3. Carcasses with back fat thickness qualifying them for the thinner one-half of the U.S. No. 2 grade but with thick muscling in the major cuts, well-balanced fleshing and uniform finish and slightly thick bellies shall be graded U.S. No. 1.
  3. U.S. No. 3 grade sow carcasses have a decidedly higher degree of finish than the minimum required to produce pork cuts of acceptable palatability. Meatiness and yield of lean cuts from carcass weight are low. Yield of fat cuts is high. The ratio of total lean and fat to bone is high. Carcasses with the minimum finish required for U.S. No. 3 grade are short and wide in relation to weight. The back and loins are very full and thick and are decidedly full at the edges. Hams are usually very thick and plump and are full in the lower part toward the hock due to a thick fat covering. Bellies are short and thick and uniform in thickness with a thick belly pocket. Shoulders are thick and full. Carcasses are usually well-balanced and uniform in fleshing and finish. There are large quantities of interior fat in the pelvic area, a moderately thick and extensive layer of fat lining the inside surface of the ribs, and slightly abundant feathering. The lean is firm. Both exterior and interior fats are firm, white, and of excellent quality. Carcasses with back fat thickness indicative of nearly minimum finish for the U.S. No. 3 grade but with thick muscling in the major cuts, well-balanced fleshing and uniform finish, and moderately thick bellies shall be graded U.S. No. 2.
  4. Medium grade. Medium grade sow carcasses have a lower degree of finish than the minimum required to produce pork cuts of acceptable palatability. Yield of lean cuts from carcass weight is moderately high. Yield of fat cuts is moderately low. The ratio of total lean and fat to bone is moderately low. Carcasses with the minimum finish required for Medium grade are long and rather narrow in relation to weight. The back and loins are rather thin, lack fullness, and slope away from the center. Hams are usually slightly thin, lack plumpness, and taper toward the hock. Bellies are long and moderately thin and are somewhat uneven in thickness with a thin belly pocket. Shoulders are moderately thin and flat. Carcasses tend to be uneven and lack uniformity of fleshing and finish. There are slightly small quantities of interior fat in the pelvic area, a thin and incomplete layer of fat lining the inside surface of the ribs, and only a small quantity of feathering. The lean is moderately soft with little evidence of marbling. Both exterior and interior fats are moderately soft, white to creamy white, and of moderately low quality. Carcasses with back fat thickness qualifying them for the fatter one-half of the Medium grade that are firm and have slightly thick bellies and belly pockets, a slightly thin but moderately extensive rib lining, and a slightly small quantity of feathering shall be graded U.S. No. 1. Carcasses with back fat thickness qualifying them for the thinner one-half of the Medium grade but with little or no rib lining and feathering, thin bellies and very thin belly pockets, and soft lean and fat shall be graded Cull.
  5. Cull grade. Cull grade sow carcasses have a decidedly lower degree of finish than the minimum required to produce pork cuts of acceptable palatability. Yield of lean cuts from carcass weight is high. Yield of fat cuts is low. The ratio of total lean and fat to bone is low. Carcasses with the degree of finish typical of the Cull grade are long and narrow in relation to weight. The back and loins are thin and decidedly lacking in fullness with a definite slope toward the sides. Hams are usually thin and flat and taper toward the hock. Bellies are very long and thin and are uneven in thickness with a very thin belly pocket. Shoulders are thin and flat. Carcasses tend to be uneven and lack uniformity of fleshing and finish. There are only small quantities of interior fat in the pelvic area, little or no fat lining the inside surface of the ribs, and scant feathering. The lean is soft and watery with very little evidence of marbling. Both exterior and interior fats are soft, creamy white to white, and of low quality. Carcasses with back fat thickness indicative of nearly maximum finish for the Cull grade that are only moderately soft and have moderately thin bellies and belly pockets, a thin and incomplete rib lining, and a small quantity of feathering shall be graded Medium.
 
Detailed Standards, Inspection Instructions & Other Resources: