Detection and quantification of Ochratoxin A in milk produced in organic farms

Dairy cows (as all other ruminants) possess physiological systems for mycotoxins’ detoxification. However, in organic farming practices the detoxification could be impaired because of possible higher contamination of feedstuff, changes in rumen pH and other factors. So the organic milk could be at risk in this respect. The results of an investigation on the presence of Ochratoxin A (OTA) in 63 samples of organic and 20 samples of conventional milk are reported in this paper. The quantification was carried out by means of the HPLC method described by Sørensen and Elbœk (2005). The method has been modified in the purification step so as to shorten the time of analysis and lower the cost of the assay. organic out of 63 “organic” samples resulted positive for OTA, with amounts ranging from 0.07 to 0.11 ppb.