terclim by ICS banner
IVES 9 IVES Conference Series 9 POTENTIAL OF PEPTIDASES FOR AVOIDING PROTEIN HAZES IN MUST AND WINE

POTENTIAL OF PEPTIDASES FOR AVOIDING PROTEIN HAZES IN MUST AND WINE

Abstract

Haze formation in wine during transportation and storage is an important issue for winemakers, since turbid wines are unacceptable for sale. Such haze often results from aggregation of unstable grape proteinaceous colloids. To date, foreseeably unstable wines need to be treated with bentonite to remove these, while excessive quantities, which are often required, affect the wine volume and quality (Cosme et al. 2020). One solution to avoid these drawbacks might be the use of peptidases. Marangon et al. (2012) reported that Aspergillopepsins I and II were able to hydrolyse the respective haze-relevant proteins in combination with a flash pasteurisation. In 2021, the OIV approved this enzymatic treatment for wine stabilisation (OIV-OENO 541A and 541B).

Herein, we aimed to gain an improved understanding of the influence of this peptidase treatment on the colloids and the quality of must and wine. For this purpose, naturally present colloids were removed from a must and wine by ultrafiltration and replaced by protein-rich, well-characterized must and wine colloids, respectively. Subsequent enzymatic treatments were performed in duplicate on technical scale (ca. 60 L for must, 16 L for wine) by adding two aspergillopepsins separately to the musts and wine followed by a brief heating to 80 °C. Control batches were treated identically, except for enzyme addition. Aliquots (each 30 L) of the treated musts were fermented. The composition and concentration of the colloids in the treated musts and wines were determined chromatographically. Haze forming potential was assessed by the heat test. The influence of the peptidases on the quality of the resulting musts and wines was investigated by sensory trials (triangle tests).

Size exclusion chromatography showed a reduction of the proteins in the musts by the enzyme treatment of about 80% as compared to a 15% reduction for the heat treatment without enzyme. Fermentation of the enzyme-treated musts resulted in stable wines, while the wines from the must without enzyme addition were unstable. The treatment of the wine showed only minor reductions of proteins (19%) in all wines. An effect of the enzyme treatment on the carbohydrates or sensory differences were not observed in comparison to the treatment without enzyme.

In brief, we provide new insights into the influence of the OIV-approved peptidase treatment with aspergillopepsin on colloids and wine quality, which will help achieve greater acceptance from wine makers.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Wendell Albuquerque², Katharina Happel³, Martin Gand², Holger Zorn2,3, Frank Will¹, Ralf Schweiggert¹

1. Department of Beverage Research, Geisenheim University, 65366 Geisenheim, Germany
2. Institute of Food Chemistry and Food Biotechnology, Justus Liebig University Giessen, 35392 Giessen, Germany
3. Fraunhofer Institute for Molecular Biology and Applied Ecology, 35392 Giessen, Germany

Contact the author*

Keywords

protein haze, peptidases, wine protein, wine stabilization

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

INTENSE PULSED LIGHT FOR VINEYARD WASTEWATER: A PROMISING NEW PROCESS OF DEGRADATION FOR PESTICIDES

The use of pesticides for vine growing is responsible for generating an important volume of wastewater. In 2009, 13 processes were authorized for wastewater treatment but they are expensive and the toxicological impact of the secondary metabolites that are formed is not clearly established. Recently photodecomposition processes have been studied and proved an effectiveness to degrade pesticides and to modify their structures (Maheswari et al., 2010, Lassale et al., 2014). In this field, Pulsed Light (PL) seems to be an interesting and efficient process (Baranda et al., 2017). Therefore, the aim of this work was to investigate the PL technology as a new process for the degradation of pesticides.

ESTIMATING THE INITIAL OXYGEN RELEASE (IOR) OF CORK CLOSURES

Many factors influence aging of bottled wine, oxygen transfer through the closure is included. The maximum uptake of wine before oxidation begins varies from 60 mg.L-¹ to 180 mg.L-1 for white and red wines respectively [1].
The process of bottling may lead to considerable amounts of oxygen. The actual contribution of the transfer through the closure system becomes relevant at the bottle storage, but the amounts are small compared to prepacking operations [2] and to the total oxygen attained during filling.

ANTI-TRANSPIRANT MODULATION OF GRAPE RIPENING: EFFECTS ON MERLOT VINE DEVELOPMENT AND ROSÉ WINE PHENOLIC AND AROMATIC PROFILES

Climate changes are impacting viticultural regions throughout the world with temperature increases being most prevalent.1 These changes will not only impact the regions capable of growing grapes, but also
the grapes that can be grown.2 As temperatures rise the growing degree days increase and with it the sugar accumulation within the berries and subsequent alcohol levels in wine. Consequently, viticultural
practices need to be examined to decrease the levels of sugars.

WHITE WINES OXIDATIVE STABILITY: A 2-VINTAGE STUDY OF CHARDONNAY CHAMPAGNE BASE WINES AGED ON LEES IN BARRELS

Ultra-premium champagne wines are characterized by a long stay on laths. The goal of the winemaker is to use all possible oenological techniques to keep the aromatic freshness of the future products. To that purpose, some champagne base wines can be aged on lees in oak barrels. However, if it is now acknowledged that such ageing practices contribute to the oxidative stability of dry white wines, no study has been done on Chardonnay champagne base wines designed for a long ageing on laths [1].

CHARACTERIZATION OF ENOLOGICAL OAK TANNIN EXTRACTS BY MULTI-ANALYTICAL METHODS APPROACH

Oak tannin extracts are commonly used to improve wine properties. The main polyphenols found in oak wood extracts are ellagitannins¹ that release ellagic acid upon hydrolysis and comprise numerous structures². Moreover, oak tannin extracts contain other compounds giving a complex mixture. Consequently, the official OIV method based on gravimetric analysis of the tannin fraction adsorbed on polyvinylpolypyrrolidone is not sufficient to describe their composition and highlight their chemical diversity.