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…

WINE LEES AS A SOURCE OF NITROGEN FOR OENOCOCCUS OENI TO IMPROVE MALOLACTIC FERMENTATION PERFORMANCE

Malolactic fermentation (MLF) is a desired process in red and acidic white wines, after alcoholic fermentation (AF), carried out by the lactic acid bacterium (LAB) Oenococcus oeni. The advantages are an increase of pH, microbiological stabilization and organoleptic improvement of the final wine. However, the presence of stress factors such as ethanol, low pH, high total SO2, lack of nutrients and presence of inhibitors, could affect the successful completion of MLF [1]. Changes in amino acid composition and deficiencies in peptides after AF, showed that MLF can be delayed, signaling its importance for bacterial growth and L-malic acid degradation during MLF [2].

INSIGHTS ON THE ROLE OF GENES ON AROMA FORMATION OF WINES

Yeast secondary metabolism is a complex network of biochemical pathways and the genetic profile of the yeast carrying out the alcoholic fermentation is obviously important in the formation of the metabolites conferring specific odors to wine. The aim of the present research was to investigate the relative expression of genes involved in flavor compound production in eight different Saccharomyces cerevisiae strains.
Two commercial yeast strains Sc1 (S.cerevisiae x S.bayanus) and Sc2 (S.cerevisiae) and six indigenous S. cerevisiae strains (Sc3, Sc4, Sc5, Sc6, Sc7, Sc8) isolated during spontaneous fermentations were inoculated in Assyrtiko and Vidiano grape must.

OENOLOGICAL AND SUSTAINABILITY POTENTIAL OF WINES PRODUCED FROM DISEASE RESISTANT GRAPE CULTIVARS (PIWI WINES)

The strategy for sustainability in the wine sector of the EU refers to a set of practices and principles that aim to minimize the negative impact of wine production on the environment, social and economic sustainability. Sustainable wine production involves a range of practices that are designed to reduce waste, conserve resources, and promote the well-being of workers and communities.

CHARACTERIZATION AND ANTIBACTERIAL ACTIVITY OF A POLYPHENOLIC EXTRACT OBTAINED BY GREEN SUPERCRITICAL CO₂ EXTRACTION FROM RED GRAPE POMACE

Upgrading wine industry solid wastes is considered as one of the main strategies to support the circular economy. Red grape pomaces constitute a rich source of polyphenols, which have been shown to possess antioxidant properties and to provide benefits for human and animal health. The objective of this work was to obtain and characterise polyphenolic extracts from red grape pomaces via green supercritical CO₂ extraction using ethanol as a co-solvent, and to evaluate their antibacterial activity against susceptible and multidrug-resistant Escherichia coli strains of animal intestinal origin.

UNRAVELING THE CHEMICAL MECHANISM OF MND FORMATION IN RED WINE DURING BOTTLE AGING : IDENTIFICATION OF A NEW GLUCOSYLATED HYDROXYKETONE PRO-PRECURSOR

During bottle aging, the development of wine aroma through low and gradual oxygen exposure is often positive in red wines, but can be unfavorable in many cases, resulting in a rapid loss of fresh, fruity flavors. Prematurely aged wines are marked by intense prune and fig aromatic nuances that dominate the desirable bouquet achieved through aging (Pons et al., 2013). This aromatic defect, in part, is caused by the presence of 3-methyl-2,4-nonanedione (MND). MND content was shown to be lower in nonoxidized red wines and higher in oxidized red wines, which systematically exceeds the odor detection threshold (62 ng/L).