resumo
Fining agents derived from animal and mineral sources are widely used to clarify and stabilize white wines. Nevertheless, health and environmental problems are being raised, concerning the allergenic and environmental impact of some of those fining products. In this study, our aim is to validate the potential of yeast protein extracts, obtained from an alternative and safe source, naturally present in wine: oenological yeasts. Three untreated white wines were used in this work in order to evaluate the impact of these novel yeast protein extracts (YPE) in terms of the wine clarification and stabilization improvement. Two separated fining trials were thus conducted at laboratory scale and the yeast alternatives were compared with reference fining agents, obtained from mineral, animal and vegetable origins. Our results indicate that YPE were capable to promote (i) brilliance/color improvement, (ii) turbidity reduction (76-89% comparing with the untreated wines), and (iii) production of compact and homogeneous lees (44% smaller volume than obtained with bentonite). Additionally, after submitting wines to natural and forced oxidations, YPE treatments revealed (iv) different forms of colloidal stabilization, by presenting comparable or superior effects when particularly compared to casein. Altogether, this study reveals that YPE represent a promising alternative for white wine fining, since they are resultant from a natural and more sustainable origin, at present not regarded as potential allergenic according to Regulation (EC) No. 1169/2011.
palavras-chave
SACCHAROMYCES-CEREVISIAE MANNOPROTEINS; FINING AGENTS; RED WINE; SENSORY CHARACTERISTICS; POTASSIUM CASEINATE; PHENOLIC-COMPOUNDS; CANDIDA-ALBICANS; MOLECULAR-WEIGHT; BENTONITE; HAZE
categoria
Chemistry
autores
Fernandes, JP; Neto, R; Centeno, F; Teixeira, MD; Gomes, AC
nossos autores
Rodrigo de Sousa Trêpa Alves Neto
Estudante de doutoramentoagradecimentos
This work is supported by the BioClarVino project (Ref. FCOMP-01-0202-EEDER-021576) financed with funds from FEDER through the COMPETE/QREN program and by the Holiwine project (Ref. ECOMP-01-0124-FEDER-027411) financed with funds from FEDER through the COMPETE/ECT (Eundacao para a Ciencia e Tecnologia) program. This work is also financed by FCT through a PhD grant attributed to IF (SEM/BD/87649/2012).