Abstract The effect of the variety (Gala, Lis Gala and Fuji Suprema) and the ripening stage (unripe, ripe and senescent) of apples on the phenolic compounds (HPLC) and antioxidant capacity (FRAP and DPPH) of apple juices and ciders were evaluated. The phenolic content of the Gala and Lis Gala apple juices decreased from the unripe to ripe stages and increased from the ripe to the senescent stages, while in the case of Fuji Suprema these values decreased with senescence. Fermentation caused a reduction (17 to 50%) of phenolics and the most affected were hydroxycinnamic acids and flavanols. Principal component analysis confirmed the influence of variety, and the use of multivariate regression (PLS) made it possible to create significant models (p < 0.05) to predict the antioxidant activity. The phenolic composition of the juices at different ripening stages was related to the variety of apple, which influenced the effect of fermentation on these compounds.

The objective of this work was to study the malolactic bioconversion in low acidity cider, according Brazilian conditions. The apple must was inoculated with Saccharomyces cerevisiae or S. cerevisiae with Oenococcus oeni. The control contained the indigenous microorganisms. Fermentation assays were carried out with clarified apple must from the Gala variety. At the beginning of fermentation, there was a fast growth of the non-Saccharomyces yeast population. Competitive inhibition occurred in all the assays, either with inoculated or indigenous populations of the yeast. The lactic acid bacteria count was ca. 1.41·10²CFU/mL at the beginning and 10(6)CFU/mL after yeast cells autolysis. The lactic bacteria O. oeni reached the highest population (10(7)CFU/mL) when added to the apple must after the decline of the yeast. The malic acid was totally consumed during the alcoholic fermentation period (80.0 to 95.5 %) and lactic acid was still synthesized during the 35 days of malolactic fermentation. These results could be important in order to achieve a high quality brut, or sec cider obtained from the dessert apple must.