United States Department of Agriculture, Agricultural Marketing Service

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Official guidance

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US

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primary

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none

Retrieved

2026-08-13

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Read and citable

Original document

Settles two naming questions that circulate endlessly and are rarely sourced. Item 406, Pork Shoulder Butt Bone-In, states outright that it 'may also be referred to as the Boston Butt or Blade'; item 422, Pork Loin Back Ribs, that it 'may also be referred to as Baby Back Ribs'. Also fixes St Louis-style as a TRIM rather than a cut: 416A is item 416 spareribs with the sternum and the ventral portion of the costal cartilages removed.

Terminology, Technical

• Explicitly not safety: A purchase specification defines cuts and trim, not safety endpoints.

• “This item may also be referred to as the “Boston Butt” or “Blade”.”

  IMPS item 406, Pork Shoulder Butt Bone-In, is the shoulder with the picnic removed, and the specification states it may also be referred to as the Boston Butt or Blade.

  The FRONT shoulder. Item 405 is the picnic, the lower arm portion of the same shoulder.

• “This item may also be referred to as “Baby Back Ribs”.”

  IMPS item 422, Pork Loin Back Ribs, shall consist of at least eight ribs and related intercostal muscle from a loin, and the specification states it may also be referred to as Baby Back Ribs.

  From the LOIN, above the spareribs, which come off the belly.

• IMPS item 416A, Pork Spareribs St. Louis Style, is item 416 spareribs with the sternum and the ventral portion of the costal cartilages removed along with the flank portion. Item 416 spareribs shall contain at least 11 ribs.

  A trim of another item, not a distinct anatomy — which is why a butcher can produce one to order from a spare rack.

• IMPS item 408, Pork Belly, is prepared from the side after removal of the leg, shoulder, loin, fat back and spareribs, with all bones and cartilages removed and practically all leaf fat removed.

  The spareribs come off the belly before it becomes item 408, which is why the two are alternatives from one region rather than independent cuts.

• The US pork specification states its own vernacular names: item 406, Pork Shoulder Butt Bone-In, 'may also be referred to as the Boston Butt or Blade'; item 422, Pork Loin Back Ribs, 'may also be referred to as Baby Back Ribs'; and item 416A defines St Louis style as spareribs with the sternum and ventral costal cartilages removed — a trim of item 416 rather than a separate cut.

If this source changes, these are the claims that need rechecking. That is the point of recording provenance per claim rather than per page.