The presence of buffer capacity-substance in red wine was supposed from the reason that pH of red wine was generally higher than that of white wine in spite of a little difference of total acidity among them.The buffer-substance (s) was adsorbed by charcoal powder, dissolved with methanol, not adsorbed with ion exchanger, Amberlite IRC 50 and IR 120 B, and adsorbed with IRA 410.
On the paper chromatogram (butanol-acetic acid-water, 4: 1: 5), Rf of the substance was observed 0.5-0.7;pale blue fluorescence under UV and blue violet coloration with spray of Folin's reagent.
From above results, it was recognized that the buffer-substance was polyphenolic substance.
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