Pork trimmings: what 80/20 and 70/30 mean

"80/20 pork trimmings" means 80 % lean and 20 % fat by weight: the first figure is always the lean fraction, and the two always sum to 100. It is a commercial description of a blend, not a laboratory result: unless the contract says otherwise it is assessed by eye on the boning line.

The nomenclature

Ratios are written lean-first: the intended proportion of lean muscle to fatty tissue before any measurement is taken. The convention is the same in chilled and frozen trade, and says nothing about boneless, rindless or skin-on status — separate points on the specification.

The table below sets out how the common grades are understood in the trade — convention, not rule: no EU or ISO instrument defines them, and each processor blends to its own recipe.

How the ratio is actually assessed

Four different things happen under the same label, and only two measure anything.

Visual grading. An operator judges cuttings against reference material as they leave the boning line — the usual basis in trimmings trade.

Formulation control. Streams of known nominal ratio are combined to a calculated target — arithmetic applied to inputs graded by eye.

Inline instrumentation. Near-infrared or X-ray systems on the mincing line estimate fat continuously against laboratory calibration. They measure a proxy and inherit its accuracy.

Laboratory analysis. A homogenised sample is analysed for fat by a named reference method — the only basis that yields a defensible number in a dispute.

Why visual lean is a specification, not a guarantee

A visual ratio counts tissue. A chemical analysis counts lipid. These are not the same quantity.

Adipose tissue is not pure lipid — it carries water, protein and connective tissue. Lean muscle is not lipid-free — it carries intramuscular fat. Material correctly graded as visual 80/20 will therefore not, as a matter of course, analyse at exactly 20 % fat, and the gap varies with the material.

Other sources of divergence:

• Carcase-to-carcase variation in fat cover and intramuscular fat; the primals of origin
• Genetics, feeding regime and seasonality in the supplying herd
• Sampling: one core does not represent a block, nor one block a container
• Moisture loss and purge between production and arrival

So a ratio alone is an agreed description of the goods, not a warranty of an analytical outcome. If you need one, the contract must set out method, sampling plan, tolerance band and who tests.

Chemical lean testing

Chemical lean (CL) is conventionally 100 minus the chemically determined fat percentage, so 95CL analyses at 5 % fat. Neither CL nor the ratio form is defined in EU law: they are trade conventions for the same property, so the basis must be written down when both meet in one contract.

Extraction principles differ: ISO 1443 frees bound lipid by acid hydrolysis before extracting, while ISO 1444 measures free fat only; the two need not agree. Name the method, not merely "fat %".

Collagen is a separate limit

Under Regulation (EU) No 1169/2011, Annex VII, Part B, point 17, skeletal muscle used as an ingredient of another food may be designated "… meat" — "pork" in English labelling — only where, for porcines, fat does not exceed 30 % and the collagen/meat protein ratio does not exceed 25 %; collagen content means hydroxyproline × 8. Exceed them while meeting every other criterion and the "… meat" figure must be adjusted down, with the fat and/or connective tissue named in the ingredient list.

Minced meat sits elsewhere: Annex VI, Part B of the same Regulation, not the hygiene rules. Checked on the basis of a daily average, minced meat containing pigmeat must not exceed 30 % fat and a collagen/meat protein ratio of 18 %; lean minced meat is held to 7 % and 12 %.

Regulation (EC) No 853/2004, Annex III, Section V governs the raw material instead: Chapter II, point 1(b) requires raw material for minced meat to derive from skeletal muscle including adherent fatty tissues, and point 1(c)(i) excludes scrap cuttings and scrap trimmings other than whole muscle cuttings. Chapter III adds a six-day limit from slaughter for minced meat made from chilled non-poultry meat. Hence "trimmings" on an invoice needs a defined meaning, and the age of the material can matter as much as its ratio.

Customs follows composition

Trimmings carrying lean are meat of swine: Harmonized System heading 02.03, in practice subheadings 0203.19 (fresh or chilled) and 0203.29 (frozen). Pig fat free of lean meat, not rendered or otherwise extracted, sits in 02.09, subheading 0209.10; Note 1(d) to HS Chapter 2 sends animal fat other than heading 02.09 products to Chapter 15, where rendered pig fat and lard fall in 15.01. A very fat trim and a pure fat trim can therefore attract different duty treatment, so confirm the 8-digit CN/TARIC code against composition, not the grade name.

What this means for your order

• State the basis explicitly: nominal visual ratio, or an analytically determined fat percentage.
• If analytical, name the method, the laboratory, the sampling plan and the tolerance band.
• Say whether the criterion applies per lot or as a production-period average — acceptance differs sharply.
• Specify collagen separately where the material feeds a labelled product.
• Record the physical spec: boneless or bone-in, rindless or skin-on, chilled or frozen, block or carton.
• Check the tariff heading against composition, not the name of the grade.