Meat Testing
Testing Meat for Molds, Yeasts and Mycotoxins in Mexico
Fungal testing counts molds and yeasts that spoil meat and dry-cured products and measures mycotoxins such as aflatoxins that can reach animals through moldy feed.
What is tested and why
Molds and yeasts grow on meat that is stored too long, dried, cured or vacuum-packed with poor hygiene. A mold and yeast count (CFU/g) is a hygiene and shelf-life indicator, especially for chorizo, longaniza, cecina, dry-aged beef and jerky. The Mexican method is NOM-111-SSA1-1994.
Mycotoxins are toxins produced by fungi. In the Yucatán Peninsula's hot, humid climate, stored corn, sorghum and concentrates can develop aflatoxins; animals eating contaminated feed can carry residues into liver and milk. For producers, testing the feed is usually more useful than testing the meat.
- Mold and yeast count (CFU/g)
- Mold identification (genus) when visible growth appears
- Aflatoxins B1, B2, G1, G2 (and M1 in milk)
- Ochratoxin A in dry-cured and dry-aged products
- Multi-mycotoxin panel in feed (aflatoxins, zearalenone, ochratoxin, T-2, fumonisins)
Sampling and shipping
For counts, send 100-250 g of product chilled in a sterile bag. For dry-cured products, send the whole piece or a sealed retail pack. For feed, take many small sub-samples across the lot (sacks or silo), mix them, and send about 1 kg in a paper or cloth bag kept dry; mycotoxins are unevenly distributed, so a single handful is not representative.
Costs
Mold and yeast counts are inexpensive: MXN 229 at the Quintana Roo state lab (2025), 401 at an ema lab (2023) and 457 + IVA at Bufete Químico. Total aflatoxins cost MXN 2,225 + IVA (Bufete Químico), and UNAM FMVZ lists a mycotoxin panel (aflatoxins, zearalenone, ochratoxin, T-2) at MXN 1,750 and fumonisin at 900.
Common tests & typical costs
| Test | Method | Cost (MXN) | Turnaround |
|---|---|---|---|
| Mold and yeast count Spoilage and hygiene indicator, key for cured products. | Plate count, NOM-111-SSA1-1994 | $229–$457 | 5-10 days |
| Mold identification (genus level) Distinguishes starter cultures from contaminants such as Aspergillus or Penicillium. | Culture + microscopy / MALDI-TOF | $600–$2,000* | 7-14 days |
| Total aflatoxins (feed, liver, product) Carcinogenic toxins from Aspergillus in stored grain. | Immunoaffinity column (NOM-186/NOM-247 methods) + fluorometry/HPLC | $2,225–$2,225 | 10 days |
| Mycotoxin panel in feed (aflatoxins, zearalenone, ochratoxin, T-2) Screens the ration before it reaches animals. | ELISA / chromatography | $1,750–$1,750 | 7-15 days |
| Fumonisins in feed Corn-borne toxin, relevant for pigs and horses. | ELISA / chromatography | $900–$900 | 7-15 days |
| Ochratoxin A in cured or dry-aged meat Mold toxin that can form on long-ripened products. | Immunoaffinity + HPLC-FLD / LC-MS/MS | $1,800–$4,500* | 10-15 days |
* Estimated range. Always request a written quote from the lab.
Mexican regulations
- NOM-111-SSA1-1994: Method for counting molds and yeasts in foods
- NOM-213-SSA1-2018: Processed meat products: sanitary specifications and test methods
- NOM-251-SSA1-2009: Hygiene practices for processing food, beverages and supplements
- NOM-061-ZOO-1999: Zoosanitary specifications for animal feed products
Where to get it tested
COFEPRIS's national reference lab; it sets the CCAYAC methods and authorizes third-party labs (terceros autorizados). Use its list to find authorized labs whose results COFEPRIS accepts.
Mexico City (national reference) · Federal reference laboratory
Accepts private clients; publishes a service catalog (rev. 6, Nov 2025) with prices: Salmonella MXN 408, Listeria 633, molds/yeasts 229, histamine 3,031, hepatitis A RT-PCR 3,500, Gnathostoma 220. Samples Mon-Fri 8:30-13:30; quotes by email (lespqroo@hotmail.com). Turnaround: 10 business days microbiology, 8 PCR, 25 toxicology.
Av. Maxuxac s/n con Calle Miguel Alemán, Fracc. Residencial Chetumal, C.P. 77039, Chetumal, Quintana Roo · COFEPRIS third-party authorized lab; quality system under NMX-EC-17025-IMNC-2018
State public health lab of the Federal Sanitary System; analyzes food and water for state surveillance. Ask the Servicios de Salud de Yucatán whether it accepts private samples and for its current fees, which were not published online when we checked.
Mérida, Yucatán
Publishes a price list: proximate MXN 1,400, fatty-acid profile 7,000, vitamins 7,300-7,900, minerals/heavy metals 600 per element (+250 each additional), mycotoxins 1,750, labeling package 15,000. Accepts meat samples refrigerated in clean plastic bags. Phones listed on the price list.
Circuito Exterior, Ciudad Universitaria, Coyoacán, CDMX
- SGS de México – food laboratory Private
Food lab offering microbiology (including Salmonella and Listeria by PCR), proximate/nutrition-label analyses and trace metals. Received COFEPRIS authorization in 2024. Prices on quote.
Naucalpan, Estado de México · ema ISO/IEC 17025:2018; COFEPRIS authorization (2024)
- Mérieux NutriSciences México Private
International food-testing group (formerly Silliker in Mexico) offering microbiology, chemistry, labeling and audits. It agreed in 2024 to acquire Bureau Veritas' global food-testing business. Prices on quote.
Labs reported in Querétaro, Guadalajara and Mexico City
- Bufete Químico, S.A. de C.V. Private
Publishes a full tariff (prices + IVA, 10-day service, MXN 561 sampling visit): Salmonella 679, Listeria 1,730, S. aureus 655, molds/yeasts 457, protein 749, fatty acids 2,843, metals 803-808, aflatoxins 2,225, nitrites 1,236. Accreditation 22LEC005 was listed valid to 04/08/2026; confirm renewal.
Dr. Atl 286, Col. Santa María la Ribera, Cuauhtémoc, CDMX · ema / MAAC (22LEC005)
Frequently Asked Questions
Is white mold on salami or dry-aged beef dangerous?
Some surface molds are intentional in traditional curing, but unexpected or colored growth should be identified. A mold count and identification will tell you whether it is a starter culture or contamination.
Should I test meat or feed for aflatoxins?
Test the feed first; it is cheaper and prevents the problem. Test liver or milk if you suspect animals already ate contaminated feed.
What level of molds and yeasts is acceptable?
Limits depend on the product and NOM; ask the lab to compare your result with the specification in NOM-213-SSA1-2018 for processed meats or your buyer's specification.