Spectroscopic Analysis of Wine Crystals

Samples of crystalline material found in bottled wines were analyzed according to their vibrational spectra using both infrared and Raman techniques. The samples were identified as either KHC 4 H 4 O 6 or CaC 4 H 4 O 6 • 4H 2 O with the latter compound growing most often on the cork. In one unique case, crystals of both compounds were found growing together. Vibrational spectroscopy proved to be a sensitive and rapid method for analyzing deposits in wines.