Abstract

CANAS, Sara; SUN, Baoshan; COIMBRA, Luis  and  BARROCA, João. Effects of sterilising filtration on microbiological stability, chemical composition and sensory properties of red wine. Ciência Téc. Vitiv. [online]. 2011, vol.26, n.2, pp.77-83. ISSN 0254-0223.

It was studied the effects of the sterilising filtration on the microbiological stability, chemical composition and sensory properties of a red wine that has not undergone malolactic fermentation and that needed to be bottled. The filtration was performed in a pilot-scale system composed by a set of membranes in series: a prefiltratiomembrane of 5 µm (fiberglass), followed by the sterilising membranes of 1 µm (fiberglass), 0.6 8µm (fiberglass) and 0.45 µm (polyethersulfone). The results obtained showed that the levels of microorganisms decreased considerably after the sterilising filtration, without detection of microorganisms at the wines filtered with the membranes of 0.6 µm and 0.45 µm. The total phenolic content and the chromatic characteristics of the filtered wines were affected by the procedure under study, varying over the time of storage. After two months of storage, the filtered wine cannot be distinguished from the non-filtered wine by their phenolic content, being the wine filtered with the 0.6 µm membrane more similar to the control group. Except for lightness, there was a remarkable positive evolution of the chromatic characteristics of the wine, especially in the wine filtered with 0.45 µm. This suggests that two months after filtration the wines have actually reached its balance, along with the required microbiological stability. From the sensory point of view, there were no significant effects on the colour intensity, aroma quality, flavour quality and overall quality of the filtered wines after one month of storage. After two months of storage, there was a significant increment on colour intensity, which is in agreement with the effects observed in the chromatic characteristics. Although there were no significant differences among wines in the other sensory properties, there was a preference, corresponding to high quality, for the wine filtered with 1 µm membrane, followed by the wine filtered with 0.6 µm membrane.

Keywords : Sterilising filtration; red wine; microbiological stability; chemical composition; sensory properties.

        · abstract in Portuguese     · text in English     · English ( pdf )