Aflatoxin M1 in cow, sheep, and donkey milk produced in Sicily, Southern Italy

Abstract

Samples (n = 485) of raw (n = 394) or heat-treated (n = 91) milk of three different species (cow, n = 170; sheep, n = 133; donkey, n = 84), collected 2013-2016 in Western Sicily (Southern Italy), were analyzed for aflatoxin M₁ (AFM₁) by enzyme-linked immunosorbent assay (ELISA). Positive ELISA results were further analyzed by HPLC with fluorescence detection. Both methods had a detection limit for AFM₁ in milk of 7 ng kg^-1. ELISA yielded 12.9 and 5% positives in cows and sheep milk, respectively, all samples of donkey milk were negative. Levels of AFM₁ were in most cases at 0.007-< 0.05 μg kg^-1, only two samples (sheep milk) slightly exceeded the European Union maximum level of 0.05 μg kg^-1. Only 6% of the samples were positive for AFM₁ in a concentration range of 0.008-0.15 μg kg^-1. Only milk samples collected directly from farms were positive. Overall, the levels were much lower than previously reported for Southern Italy cow and sheep milk samples purchased in retail stores. The results of this work indicate a continuous improvement of the feeding techniques on dairy farms of Southern Italy, which is essential to ensure consumers' protection.

Keywords: Aflatoxin; Donkey; ELISA; HPLC-FLD; Milk.