Towards high resolution H-1 NMR spectra of tannin colloidal aggregates

The time dependent colloidal formation of tannins in hydro-alcoholic medium has been studied by H-1-NMR, Line broadening observed with time can be can celled by making use of magic angle sample spinning (MASS) thus yielding sh arp lines that allow structural studies. We used as an example catechin, a constitutive monomer of Bordeaux young red wine tannins. Chemical shift var iations of polyphenol protons allow monitoring the time course of aggregati on.