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IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Influence of protein stabilization with aspergillopepsin I on wine aroma composition

Influence of protein stabilization with aspergillopepsin I on wine aroma composition

Abstract

The protein haze formation in white and rosé wines during storage, shipping and commercialization has always been an important issue for winemakers. Among the various solutions industrially proposed, the use of bentonite is certainly the most widespread. However, the harmful effects of this treatment are known either in terms of wine volume loss and wine flavour and aroma. The use of aspergillopepsin I -an acid endoprotease from Aspergillus spp- in must and wine has been recently approved by OIV and the European Commission for protein stability, coupled to a heat treatment. Beyond the established efficacy of this approach on wine stability, little is known about its influence on the wine aroma profile. The present study aims to evaluate the combined effect of heat treatment with proteases (HP) in musts on the concentration of 74 wine aroma compounds at lab and semi-industrial scale.  Eight grape musts were treated with acid proteases and heated at 70°C for the lab-scale trials, and the concentrations of wine volatile compounds at the end of the alcoholic fermentation were compared with those deriving form a traditional white and rosé winemaking protocol. The must treatment induced a significant increase (one-way ANOVA, Tukey’s HSD p

DOI:

Publication date: June 27, 2022

Issue: IVAS 2022

Type: Poster

Authors

Gallo Adelaide1, Paolini Mauro1, Tonidandel Loris1, Leonardelli Andrea1, Barbero-Fondazione Alice1, Celotti Emilio2, Natolino Andrea2, Schneider Rémi3, Larcher Roberto1 and Roman Tomas1

1Fondazione Edmund Mach—Technology Transfer Center
2Università degli Studi di Udine—Dipartimento di Scienze Agroalimentari, Ambientali e Animali
3Oenobrands SAS Parc Agropolis II

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Keywords

wine aroma, proteases, heat treatment, protein haze

Tags

IVAS 2022 | IVES Conference Series

Citation

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