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The recovery of tartaric acid (TA) from three industrial enological wastes: (i) cream of tartar, (ii) lees, and (iii) eluates from the regeneration of anion exchange resins used for the production of grape liquid sugar, was studied. Recovery of TA ranged between 58 and 99%, the highest being from cream of tartar. The level of addition of calcium salts is important to improve the recovery of calcium tartrate from lees and eluates. A signi®cant inverse correlation between TA recovery and the percentage of organic acids, except for tartaric acid, was found; this index may help to optimize the level of calcium addition. Enological eluates would represent a commercial source of malic acid (recovery of 51%).

A high-performance liquid chromatographic method is proposed for the simultaneous separation of main carboxylic acids, carbohydrates, ethanol, glycerol, and 5-HMF in beer by direct injection. A column packed with a sulfonated divinyl benzene-styrene copolymer and an isocratic elution with 0.0045N sulfuric acid and acetonitrile (6%, v/v) are employed. UV and refractive index detectors connected in series are also used to reduce the matrix interference of phenolic compounds. In conditions described, nine compounds are quantitated in a single chromatographic run without any pretreatment except for sample dilution and filtration before injection. Precision, accuracy, linearity of response, limit of detection, and limit of quantitation are also evaluated for each compound. Satisfactory results are obtained to justify the application of this method to all phases of beer production for process and quality control.