The proteome Argonauts: conquering the “golden fleece” of alcoholic beverages and soft drinks via combinatorial peptide ligands

Proteomic science has been vastly exploited in the past ten years for biomarker discovery in sera, in search of panels of proteins able to warn about the onset of various diseases. According to Mitchell (Nature Biotech. 28, 2010, 665-670), this has been the biggest “fiasco” in this arena, with billions of dollars wasted. Completely different results have been obtained by us when analyzing a “fiasco” (a 1.5 liter jug) of white or red wine, with the combinatorial peptide ligand library (CPLL) technology. It turns out that most wine producers treat white wines with casein (and red wines with egg albumen) in order to eliminate residual grape proteins that would flocculate upon long term storage. Although required by EC rulers, no producer has ever stated the residual amount of these allergenic additives in their product. With the CPLL technology, we were able to detect as little as 1 µg casein/L, an extremely high detection sensitivity, unreported up to the present (the official ELISA test of the EC reached barely down to 200 µg/L). However, if untreated wines are analyzed, we can detect well over 100 residual grape proteins present in wines, this suggesting the possibility of proteo-typing grand crus against counterfeited products invading the market. We will additionally report proteo-typing of beers as well as different carbonated soft beverages. One could thus easily distinguish among artificial beverages, made only with synthetic additives and flavours (Coca Cola being a classical example) vs. genuine products made with plant extracts. Regulatory agencies and customers would thus have a new, formidable tool for protection against adulterated and counterfeited foodstuff and beverages.