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An analytical comparison of three different techniques for quantitative profile of esters in cachaca is reported. The Ministerio da Agricultura Pecuaria e Abastecimento (MAPA) recommends the use of GC/FID or volumetry. Despite being laborious and lacking in chemical speciation, the volumetric technique for total ester content shows to be appropriate, reproducible, and accurate for the analysis of cachaca. However, the GC/FID suggested by MAPA, considering only ethyl acetate, shows inaccuracy, underestimating the total ester content by a median factor of 72%, mainly due to the absence of ethyl lactate analysis. On the other hand, the GC/MS technique that comprises the analysis and speciation of nine esters, including ethyl lactate, proved to be reproducible, simple, fast and accurate for the analysis of total ester content in cachaca. Thus, the total ester content results obtained using GC/FID must be considered with precaution.

O objetivo do trabalho foi avaliar o efeito da fermentação maloláctica (FML) na composição dos vinhos Cabernet Franc, Cabernet Sauvignon e Isabel, elaborados em pequena escala na safra de 1995. Dezoito variáveis foram avaliadas antes e após a FML. Os resultados mostraram que houve degradação do ácido málico; diminuição da acidez total, do extrato seco, do extrato seco reduzido e da intensidade de cor; e aumento do pH, da acidez volátil, da relação álcool em peso/extrato seco reduzido e da relação I420/I520. Entre os compostos voláteis, verificou-se a formação de lactato de etila e da acetoína. The objective of the work was to evaluate the effect of malolactic fermentation (MLF) on the composition of Cabernet Franc, Cabernet Sauvignon and Isabella wines, elaborated on a small scale during the 1995 vintage. Eighteen variables were evaluated before and after MLF. The results showed that MLF degraded the malic acid, decreased the total acidity, the dry extract, the reduced dry extract and color intensity and increased the pH, the volatile acidity, the alcohol in weight/reduced dry extract ratio and the A420/A520 ratio. Among the volatile compounds it was observed the formation of ethyl lactate and acetoin.