Aflatoxins are a type of highly toxic mycotoxin produced by fungal growth from genus Aspergillus flavus and Aspergillus parasiticus. Aflatoxins are found in groundnuts, tree nuts, maize, rice and other dried foods, fruits, spices, crude vegetable oil and cocoa beans because of fungal contamination before and after harvest. Aflatoxin B1 is the most common aflatoxin found in food. It is one of the most toxic and carcinogenic aflatoxins. Aflatoxins M1 and M2, present in milk and milk products, are major metabolites of Aflatoxins B1 and B2. They are produced by lactating animals consuming aflatoxin contaminated feeds. The ingested Aflatoxins B1 and B2 are metabolized by livestock into Aflatoxins M1 and M2 respectively.
Aflatoxins are heat resistant and are not destroyed by cooking or pasteurization, posing significant food safety risks to humans and animals. Exposure to aflatoxins can cause edema, liver cancer and even death. Children are particularly affected by aflatoxin exposure which leads to stunted growth, delayed development, liver damage and liver cancer.
Regulatory bodies have established action levels for aflatoxins in food and animal feed to help ensure food safety. It is, therefore, important to monitor and regularly test foods for aflatoxin contamination.
Ensuring food safety and compliance with international standards is critical for maintaining access to overseas markets.
The Ministry for Primary Industries (MPI) plays an important role in monitoring and managing aflatoxins in the New Zealand food supply.
Aflatoxin testing at AsureQuality
AsureQuality has validated an in-house liquid chromatographic method, AsureQuality (UPLC) for quantitation of Aflatoxins B1, B2, G1, G2, M1 and M2 in milk, milk powders, nutritional powders (infant formula, paediatric/ adult formulas), carbohydrate raw materials, grains, nuts and nut products, cereals, dried fruits, cheese, oils, anhydrous milk fat (AMF), protein products (lactoferrin), yogurt and cream samples.
Testing is carried out at the Chemistry department of our Auckland Laboratory.
Sampling
Aflatoxin contamination of particulate products, such as, nuts and grains, is likely to occur in pockets, which may be randomly distributed. Sampling must be performed keeping this in mind to ensure a true representative of the whole sample size is taken for testing.
For import purposes, sampling is conducted by an Authorised Health Officer on behalf of the customer. Each lot normally consists of up to twenty-two 500-gram samples per import consignment. A maximum of five individual samples should be composited.
For peanut butter, two units should be sampled per lot and tested as a composite. Each unit should be at least 500 grams.
For the local market, sample size may be less than 500 grams.
More information
For further detail, please read: Aflatoxins B1, B2, G1, G2, M1 and M2 Analysis (customer sign in required)