Red wine and model wine astringency as affected by malic and lactic acid

Red wines and model solutions containing grape seed phenols were assessed for perceived astringency, bitterness and sourness by a panel of trained assessors using time-intensity (T-I) methodology. The effect of lactic and malic acid on perception of these attributes was evaluated at two pH values, by adding different amounts of acids. Maximum intensity (I-max) and total duration (T-tot) of astringency increased with decreasing pH in model solutions and red wine, but no differences were found between malic and lactic acid on perception of astringency. The pH and the acid type did not affect any of the bitterness T-I parameters. However, sourness showed an increase in I-max and T-tot with decreasing pH.