Wet versus dry: how processing rewrites the nutrition label
Why the form of the food is itself a nutrition question
A pet food's physical form — dry extruded kibble or heat-processed canned food — is not a cosmetic choice. Heat and pressure physically alter some nutrients, so the finished label changes with the process. The cleanest illustration is taurine in cats, where the same animal's requirement is written at two different levels depending on whether the food was extruded or canned.
Wet and dry: the processing divide
FEDIAF 2025 sets processing-dependent nutrient minimums where heat treatment demonstrably changes nutrient bioavailability — the clearest case being taurine in cats. Taurine bioavailability is lower when cats are fed heat-treated canned food (Hickman MA et al. 1990, 1992), so a heat-processed wet cat food needs to contain approximately 2 to 2.5 times more taurine than a dry extruded food, which should contain 0.1% DM taurine (Douglass GM et al. 1991, Earle KE et al. 1991). Heat processing degrades taurine (Morris JG et al. 1994).
The late-1980s link between commercial heat-processed cat foods and taurine-deficiency dilated cardiomyopathy (Pion P et al. 1987) drove these fortification rules.
The taurine and arginine numbers, side by side
The FEDIAF 2025 cat amino acid recommendations (Table III-4a, g per 100 g DM; adult columns for MER 75 / 100 kcal/kg BW0.67, then growth/reproduction) spell out the split explicitly:
- Taurine minimum (dry pet food) 0.13 / 0.10 g adult and 0.10 g growth/repro; (canned pet food) 0.27 / 0.20 g adult and 0.25 g growth/repro — cats synthesize inadequate taurine, and heat-processed wet food lowers taurine bioavailability so canned foods need roughly 2-2.5 times the dry-food level.
- Arginine minimum 1.30 / 1.00 g adult and 1.07/1.11 g growth/reproduction — cats are uniquely vulnerable to arginine deficiency because of urea-cycle limitations; FEDIAF notes the requirement rises with protein content (an extra 0.01 g arginine per additional gram of crude protein above the stated values, NRC 2006g).
FEDIAF also sets methionine, methionine + cystine (for which FEDIAF does not set a separate cystine minimum), lysine, threonine and tryptophan minimums. The same digestibility caveat applies: FEDIAF recommends accounting for an apparent crude protein digestibility of at least 80%; if that cannot be guaranteed, essential amino acid levels should be increased by a minimum of 10%.
How AAFCO writes the same problem
For cats, taurine is an essential amino acid (cats cannot synthesize sufficient amounts endogenously); the AAFCO cat food nutrient profile sets a taurine minimum of 0.10% DM (1000 mg/kg) on a dry-matter basis, with the US profiles dataset listing 0.10% DM for extruded (dry) and 0.20% DM (2000 mg/kg) for canned cat food. AAFCO Ch6 definition 6.12 Taurine is a product that contains a minimum of 97% 2-aminoethanesulfonic acid; the percentage of taurine must be guaranteed.
For dogs, taurine is not an AAFCO-required nutrient — dogs can synthesize it from methionine and cysteine — which is why the dog profiles set no taurine minimum.
AAFCO 2013 Official Publication established the baseline Cat Food Nutrient Profiles. Key values: Crude Protein minimum 30% DM for Growth & Reproduction, 26% DM for Adult Maintenance; Crude Fat minimum 9.0% DM for all life stages; Calcium minimum 1.0% DM (G&R) / 0.6% DM (Adult); Phosphorus minimum 0.8% DM (G&R) / 0.5% DM (Adult). Unlike dogs, the 2014 Ca split did not significantly alter cat requirements, but taurine minimums (1000 mg/kg DM dry food, 2000 mg/kg DM canned) became more prominent in 2013-2014.
China's GB/T 31217-2014 cat food standard
China writes its own complete-cat-food floor that mirrors the wet/dry taurine split. GB/T 31217-2014 (Complete pet food — Cat food, 全价宠物食品 猫粮) was issued 2014-09-03 by AQSIQ and the China National Standardization Administration and implemented 2015-03-08; it is a voluntary national standard for industrially produced complete cat food. Main physical and chemical indicators (Table 1, dry matter basis, juvenile/pregnant/lactating vs adult): crude protein ≥28.0% / ≥25.0%; crude fat ≥9.0% / ≥9.0%; crude ash ≤10.0% / ≤10.0%; crude fiber ≤9.0% / ≤9.0%; calcium ≥1.0% / ≥0.6%; total phosphorus ≥0.8% / ≥0.5%; water-soluble chloride (as Cl⁻) ≥0.3% / ≥0.3%; taurine ≥0.1% (dry food) and ≥0.2% (wet food) for both life stages.
Two structural notes matter for label readers. Calcium and phosphorus carry minima only — the standard specifies no upper limits, and it does not set requirements for vitamin A, arginine, or methionine. The moisture classification (Table 2) is what defines "wet" and "dry" in the first place: dry <14.0%, semi-moist 14.0–60.0%, wet ≥60.0%. Hygiene indicators (Table 3, 88% dry matter basis) match the dog food standard — for example fluorine ≤150 mg/kg, lead ≤5 mg/kg, aflatoxin B₁ ≤10 µg/kg, total bacteria <1×10⁴ CFU/g (except wet food), Salmonella not found in 25 g, and commercial sterility for wet food. Source: unofficial English translation in USDA GAIN Report CH2022-0063.
Complementary snacks: the "10%" myth
Processing is not the only place the label can mislead. FEDIAF 2025 distinguishes Complete and Complementary pet foods (Chapter 4; definitions per Regulation (EC) No 767/2009). A complete pet food is, by reason of its composition, sufficient for a daily ration and — when fed as the only source of nutrients for the whole of the intended life stage — covers all nutritional needs; if no life stage is specified on the label, the product is assumed to be complete for all life stages and should be formulated to the early growth and reproduction levels.
Complementary pet food covers a wide range of products, which FEDIAF divides into three categories for validation purposes: (a) products that significantly contribute to the energy content of the daily ration but are not complete (e.g., products mixed with other food components in the household, and treats/snacks normally given as rewards); (b) products that contribute to daily nutrition and may or may not add significantly to energy content (e.g., snacks supplying higher levels of omega-3 & omega-6 fatty acids); and (c) products not intended to contribute nutritionally but given to occupy the animal and that can be eaten (e.g., dog chews). Feeding instructions should reflect the intended role of the product in the total ration, and the total daily ration should still match the recommended allowances and the nutritional and legal maximum values for complete pet food. Category (a) products follow the same validation procedure as complete food; category (b) validates the nutrients relevant to intended use; category (c) needs no nutritional-adequacy validation. The guidelines do not set a fixed "<10% of daily energy" treat rule, nor do they define a dental-care symbol.
Raw diets: what the evidence cluster actually shows
The raw-diet movement inverts the question — less processing is the point. Source: Europe PMC (Europe PubMed Central) REST search — first-hand peer-reviewed abstract records, pulled 2026-07-22. Query: (("raw diet" OR "BARF" OR "raw feeding" OR "raw pet food") AND (dog OR cat)) AND HAS_ABSTRACT:"Y". The cluster returns 489 records in Europe PMC; 6 representative studies are extracted below.
What the abstracts say:
- PMID 42245978 (2026, Frontiers in veterinary science) — Raw meat-based diets (RMBD) are increasingly popular among dog guardians.
- PMID 40697637 (2025, Frontiers in veterinary science) — demand for pet foods considered "natural," raw, uncooked, minimally processed, and those free of synthetic preservatives.
- PMID 41328332 (2025, One health) — raw meat-based diets (RMBDs) raised One Health concerns regarding their microbiological and parasitological safety, particularly when raw diets are used at home.
- PMID 41822231 (2026, Frontiers in veterinary science) — Salmonella surveillance in raw pet food and dogs in Great Britain, 2013-2022.
- PMID 39943063 (2025, Animals) — Current Evidence on Raw Meat Diets in Pets: A Natural Symbol, but a Nutritional Controversy.
- PMID 42221950 (2026, Frontiers in veterinary science) — a large-scale survey (n = 8,823) investigated the feeding practices of dog and cat owners.
The through-line is a recurring One Health tension: demand for minimally processed food versus documented microbiological and parasitological risk, especially when raw diets are prepared at home.
Sources
Every figure and claim above is drawn verbatim from the following first-hand topic files in this repository. No value was inferred.
- FEDIAF_2025_wet_vs_dry_processing — processing-dependent minimums; canned taurine bioavailability; 2–2.5× factor; 0.1% DM dry; DCM history; ≥80% digestibility / +10% rule.
- FEDIAF_2025_cat_arginine_taurine — Table III-4a cat amino acid minimums (taurine, arginine, and others) for dry vs canned, adult vs growth/repro.
- AAFCO_Ch6_taurine — 97% 2-aminoethanesulfonic acid definition; 0.10% DM / 1000 mg/kg dry, 0.20% DM / 2000 mg/kg canned; dog synthesis from methionine and cysteine.
- AAFCO_2013_baseline_cat — 2013 baseline cat profiles; crude protein 30%/26% DM; fat 9.0% DM; calcium/phosphorus floors; 2014 Ca split note.
- CN_GB31217_2014_complete_cat_food — GB/T 31217-2014 tables; taurine ≥0.1% dry / ≥0.2% wet; moisture classes; hygiene limits; USDA GAIN CH2022-0063 translation.
- FEDIAF_2025_complementary_snacks — complete vs complementary split per Regulation (EC) No 767/2009; three snack categories; no fixed "<10% energy" rule.
- evidence_raw_diet_safety — Europe PMC first-hand abstracts (pulled 2026-07-22); 489-record cluster; six representative PMIDs on RMBD safety and One Health risk.