A MALDI-TOF PLATFORM FOR INTEGRATED PROTEOMIC PEPTIDOMIC PROFILING OF MILK SAMPLES ALLOWS RAPID DETECTION OF ILLEGAL FOOD ADULTERATIONS

摘要

milk is an important food for children and adult individuals. It is the constituent of products that, depending on producing animals and transformation procedures, present organoleptic/nutritional properties and economie values. Exclusive use of a specific, raw milk is mandatory in the manufacturing of traditional high-grade European Designation of Origin cheeses. However, it has been estimated that buffalo, goat sheep milk only represent 11, 2 and 1.4% of the raw material produced worldwide and for dairy productions, compared with the bovine counterpart (85%). The adulteration ,caprine and buffalo milk with common bovine material occurs often because of the prices of the first ones, compared to the latter, and the fluctuation in their availability to the corresponding seasonal shortages. Fraudulent activities are also associated with addition of powdered/frozen material to fresh milk in the period of low lactation. practices mentioned above determined an ultimate need of rapid, sensitive, methods to determine the nature of raw milk (and of the corresponding dairy . An integrated platform for combined peptidomic/proteomic profiling of milk has been developed to rapidly reveal illegal adulterations due to the addition of non-declared bovine material to water buffalo, goat and ovine milks, or of powdered Ine material to the fresh counterpart. Analysis was based on automated MALDI-TOF-measurement of milk samples. Fresh raw bovine milk (BM), water buffalo milk , ovine milk (OM) and goat milk (GM) samples were collected from locai farms after milking and assayed within 5 h. Bovine pasteurized milk (PM), UHT milk (UM) infant formula (IM) samples from different (20 in number) commercial brands were chased from supermarkets and used before their expiration date. Twenty-five samples analyzed for each type of milk. For adulteration studies, binary mixtures of BM in , OM and GM counterparts, or IM in BM were prepared at 1, 2, 5, 10, 15, 20, 30, 40 and v/v values. Peptide and protein markers of each animai milk were identified after direct of diluted skimmed and/or enriched diluted skimmed filtrate samples. In parallel, of thermal treatment were characterized in different types of commercial milks.