In-depth proteomic analysis of non-alcoholic beverages with peptide ligand libraries. I: Almond milk and orgeat syrup

Combinatorial peptide ligand libraries, both commercial and home-made, have been adopted to investigate the proteome of non-alcoholic beverages, in order to assess their genuineness and detect also trace proteins, in search of potential allergens. Two such beverages have been studied: almond milk and orgeat syrup. In the first product we have been able to identify 132 unique protein species, the deepest investigation so far of the almond proteome. In the second beverage, a handful of proteins (just 14) have been detected, belonging to a bitter almond extract. In both cases, the genuineness of such products has been verified, as well as the fact that almond milk, judging on the total protein and fat content, must have been produced with 100 g ground almonds per litre of beverage, as required by authorities. On the contrary, cheap orgeat syrups produced by local supermarkets and sold as their own brands, where found not to contain any residual proteins, suggesting that they contained only synthetic aromas and no natural plant extracts. This could be the starting point for investigating the myriad of beverages that in the last decades have invaded the shelves of supermarkets the world over, whose genuineness and natural origin have never been properly assessed.

Graphical abstractThere are rumours that even Saint Thomas of Aquinas had selected it as his preferred beverage, probably because liquors were banished from convents.Figure optionsDownload full-size imageDownload high-quality image (506 K)Download as PowerPoint slideResearch highlights► The drink that helped Crusaders survive during the siege of Jerusalem. ► Recommended also by Saint Thomas of Aquinas. ► The deepest coverage of almond's proteome so far. ► How to recognise genuine orgeat syrup from cheap imitations! ► The best alternative to intoxicating alcoholic beverages!