Pork primal cuts: an international guide

A pig carcase divides into four main primals — leg (ham), shoulder (picnic and butt, with the collar alongside), loin and belly — plus the "fifth quarter" of offal, fats and by-products. Those primals are cut on different lines and sold under different names in the EU, the US and Asia, so an international contract should identify goods by tariff code and written specification, never by a cut name alone.

The four main primals

Leg (ham)

The hind leg, sold bone-in, semi-boneless, or fully boned and seamed into its major muscles — topside/inside, silverside/outside, knuckle and rump — with the shank (hock) attached or separated.

Naming trap: in the EU, "ham" is routinely used for the fresh hind leg. In US commercial usage "ham" alone usually implies a cured product, so the raw item is written "fresh ham" or "leg". A contract drafted between the two conventions must say fresh or cured explicitly.

Shoulder: picnic, butt and collar

The forequarter yields two commercially distinct items: the lower arm portion, the picnic (UK: hand and spring; Spain: paleta), and the upper blade portion, the butt — US "Boston butt", which comes from the front of the animal, not the rear. Forward of the loin lies the collar, traded as collar butt or neck and a high-value item in Chinese, Korean and Japanese foodservice.

Spanish usage does not map onto that vocabulary. Aguja is the blade end of the forequarter, the nearest Spanish equivalent of the Boston butt; cabecera de lomo is normally the neck end of the loin — adjacent to the collar, but a different item with a different weight and muscle content. They are not synonyms, and a contract that treats them as one is a rejection waiting to happen.

Where the shoulder is separated from the loin — at which rib — is a specification decision, not a fixed rule: move the line one rib and the weight and muscle content of both primals change.

Loin

The dorsal primal, sold bone-in or as a boneless eye (longissimus). It carries the tenderloin (solomillo; UK "fillet"), the back ribs and the chop-bearing section. Another naming trap: UK back bacon is cured loin, US bacon is cured belly. "Bacon" is a process, not a cut.

Belly

The ventral primal, with or without ribs and rind. Trim, rib removal, layer definition and slab dimensions vary sharply by destination: bacon manufacture, Chinese processing and Korean grilling each want a different one.

The fifth quarter

Everything outside the four primals: head, jowl, trotters, ears, tails, offal (liver, heart, kidney, stomach, intestines), fats and bones. Edible offal of swine is not even classified with the primals: it sits in Harmonized System heading 0206, not 0203. Demand is market-specific, and eligibility depends on the destination's import conditions and certificate wording, not the exporter's preference.

Why the same cut has three names

Trade usage, not a standard.

Three forces drive it: butchery traditions cut in different places, cured and fresh products share a name in some languages and not others, and foodservice categories such as char siu collar or samgyeopsal belly have no anatomical definition at all.

What a code tells you, and what it does not

Pork sits in Harmonized System heading 0203, meat of swine, fresh, chilled or frozen. The heading divides first into fresh or chilled and frozen, then each of those into three six-digit subheadings: carcases and half-carcases; hams, shoulders and cuts thereof, with bone in; and "other". Those six digits are the internationally agreed level; the EU's Combined Nomenclature takes the code to eight, and other national tariffs add digits of their own.

The code decides the duty rate, the statistical treatment and the other measures that attach to it. It does not describe the product: at six digits a bone-in ham and a bone-in shoulder share one subheading, and "other" absorbs a very wide range of boneless cuts. The HS is revised periodically — HS 2022 is the edition in force — so confirm the code and its national extension in the destination's own tariff.

Published cutting standards close the gap. The UNECE Working Party on Agricultural Quality Standards publishes a standard for porcine meat carcases and cuts (ECE/TRADE/369/Rev.3) that describes each item by its anatomical cutting lines and gives it a structured product code. USDA AMS publishes Institutional Meat Purchase Specifications, whose Series 400 covers fresh pork. Citing one as the baseline turns a disagreement into a short list of named exceptions rather than an argument about what a word means.

What a workable specification contains

ICC describes the Incoterms® rules as clarifying the tasks, costs and risks of delivering goods from seller to buyer. They say nothing about whether the meat conforms to what was ordered; that is the specification's job.

What this means for your order

Send a specification, not a cut name: the tariff code you will declare, the published standard you work from, bone and rind status, trim level, weight range, temperature regime and packing format. Ask the destination's competent authority which certificate model and cut descriptions apply before pricing the shipment, since bone-in and boneless items are not always treated alike. Where a term is regional trade usage, define it in the contract. Ambiguity in a cut name is discovered at the border or on the intake line, and it is expensive in both places.