terclim by ICS banner
IVES 9 IVES Conference Series 9 IMPACT OF RHIZOPUS AND BOTRYTIS ON WINE FOAMING PROPERTIES

IMPACT OF RHIZOPUS AND BOTRYTIS ON WINE FOAMING PROPERTIES

Abstract

A lot of work has been done on the impact of Botrytis on the foam of sparkling wines. This work often concerns wines produced in cool regions, where Botrytis is the dominant fungal pathogen. However, in southern countries such as Spain, in particularly hot years such as 2022, the majority fungal pathogen is sometimes Rhizopus. Like Botrytis, Rhizopus is a fungus that produces an aspartic protease. The aim of this study was therefore to determine the foaming properties of wines produced with a synthetic must contaminated by a Rhizopus or Botrytis culture. In order to confirm the identification of the fungal strain, the D1-D3 domains of the 28S rRNA gene were amplified and sequenced. BLAST search indicated 100% identity with a reference strain of Rhizopus lyococcus (CBS 320.35).

The complete experimental design presents 12 modalities (AF in triplicate, i.e. 36 bottles). The fungal isolates of Botrytis cinerea (B. c.) and Rhizopus lyococcus (R. l.) were cultured using a modified version of the method described by Gimenez et al. (2022). Alcoholic fermentations (AF) were performed in 500mL glass bottles from synthetic grape must supplemented or not with 50 mg/L of epicatechin. The yeast strain S. cerevisiae Lalvin EC1118 (Lallemand) was used for the AF process. To examine the impact of the pathoge- nic fungi, 10% (v/v) of B.c. or R.l. culture were added (separately) to the model grape juice. Furthermore, two different concentrations of L-malic acid were added to the fermentation media creating two sets of conditions : 2g/L of L-malic acid (pH=3.5) and 6 g/L of L-malic acid (pH=3). The results of the wines with fungus were compared to those of the control wines obtained without fungus.

The results of this study show that the presence of Rhizopus in the must significantly or highly significantly degrades the foamability and foam stability of the wines (foam measured with the KRUSS DFA100 equipment). The analysis of the protein composition by SDS-PAGE clearly shows a degradation of the yeast proteins by the fungal proteases of Rhizopus. Surprisingly, the Botrytis strain used did not affect the foam of the wines. These differences in proteolytic activity are confirmed by using BSA as a subs- trate: the Rhizopus culture degrades the 500 mg/L BSA in a few minutes, whereas the BSA degradation by the Botrytis culture remains considerably lower despite the longer culture of the fungus. Finally, the presence of epicatechin did not affect the wines’ foaming properties.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Richard Marchal¹, Candela Ruiz De Villa Sardón², Arnau Just Borràs², Nicolas Rozès², Fernando Zamora Marín², Joan-Miquel Canals Bosch², Thomas Salmon¹, José Francisco Cano Lira³, Jacques-Emmanuel Barbier4, Sabine Gognies¹

1. Université de Reims Champagne-Ardenne, Faculté des Sciences, Laboratoire d’Oenologie, 51687 Reims CEDEX 02, France
2. Universitat Rovira i Virgili, Facultat d’Enologia, Campus Sescelades, 43007 Tarragona, Spain
3. Un+iversitat Rovira i Virgili, Mycology, Environmental Microbiology Unit, Medicine Faculty / Oenology Faculty,  Sant Llorenç 21, 43201-Reus, Spain
4. Institut Œnologique de Champagne – ZI de Mardeuil – 51201 Épernay Cedex, France 

Contact the author*

Keywords

wine foam, Rhizopus, yeast proteins, aspartic protease

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

ADDITION OF OAK WOOD ALTERNATIVE PRODUCTS: QUALITATIVE AND SENSORIAL EFFECTS FOR A WHITE WINE OF ALIGOTE

Wines matured in contact with wood are extremely popular with consumers all over the world. Oak wood allows the organoleptic characteristics of wine to be modified. Wines are enriched with volatile and non-volatile compounds extracted from the wood. The aromas extracted from oak wood contribute to the construction of the wine’s aromatic profile and the main polyphenols extracted can modify taste perceptions such as astringency and bitterness. All the compounds extracted from the wood thus contribute to the balance and quality of the wines.

REMEDIATION OF SMOKE TAINTED WINE USING MOLECULARLY IMPRINTED POLYMERS

In recent years, vineyards in Australia, the US, Canada, Chile, South Africa and Europe have been exposed to smoke from wildfires. Wines made from smoke-affected grapes often exhibit unpleasant smoky, ashy characters, attributed to the presence of smoke-derived volatile compounds, including volatile phenols (which occur in free and glycosylated forms). Various strategies for remediation of smoke tainted wine have been evaluated. The most effective strategies involve the removal of smoke taint compounds via the addition of adsorbent materials such as activated carbon, which can either be added directly or used in combination with nanofiltration. However, these treatments often simultaneously remove wine constituents responsible for desirable aroma, flavour and colour attributes.

CHARACTERISTIC EXTRACTION OF THE PHENOL COMPOUNDS IN KOSHU (VITIS VINIFERA CV.) WINE DURING THE MACERATION

Koshu is one of the indigenous grape variety that has been grown in Japan for more than one thousand years. Recent research showed that it has 70% of Vitis vinifera genes. In 2010, the Koshu variety was included in ‘International List of Vine and Varieties and their Synonyms’ managed by the ‘International Organisation of Vine and Wine’ and has further fueled its popularity in Japan. It is the most cultivated variety for winemaking in Japan.
Koshu berries have light purple skins. The variety is mainly used to produce white wines such as an aromatic wine and a wine produced by sur lie method although various styles are produced.

EMERGENCE OF INORGANIC PHOSPHONATE RESIDUES IN GRAPEVINE PLANT PARTS, BERRIES AND WINES FROM SOURCES OTHER THAN FOLIAR SPRAYING

Inorganic phosphonates are known to effectively support the control of grapevine downy mildew in vi- ticulture. Their application helps the plant to induce an earlier and more effective pathogen defense. However, inorganic phosphonates have been banned in organic viticulture due to their classification as plant protection products since October 2013. Despite the ban, phosphonate has been recently detected in organic wines.

Microbial ecosystems in wineries – molecular interactions between species and modelling of population dynamics

Microbial ecosystems are primary drivers of viticultural, oenological and other cellar-related processes
such as wastewater treatment. Metagenomic datasets have broadly mapped the vast microbial species
diversity of many of the relevant ecological niches within the broader wine environment, from vineyard
soils to plants and grapes to fermentation. The data highlight that species identities and diversity
significantly impact agronomic performance of vineyards as well as wine quality, but the complexity
of these systems and of microbial growth dynamics has defeated attempts to offer actionable
tools to guide or predict specific outcomes of ecosystem-based interventions.