terclim by ICS banner
IVES 9 IVES Conference Series 9 EVIDENCE OF THE INTERACTION OF ULTRASOUND AND ASPERGILLOPEPSINS I ON UNSTABLE GRAPE PROTEINS

EVIDENCE OF THE INTERACTION OF ULTRASOUND AND ASPERGILLOPEPSINS I ON UNSTABLE GRAPE PROTEINS

Abstract

Most of the effects of ultrasound (US) result from the collapse of bubbles due to cavitation. The shockwave produced is associated with shear forces, along with high localised temperatures and pressures. However, the high-speed stream, radical species formation, and heat generated during sonication may also affect the stability of some enzymes and proteins, depending on their chemical structure. Recently, Celotti et al. (2021) reported the effects of US on protein stability in wines. To investigate this further, the effect of temperature (40°C and 70°C; 60s), sonication (20 kHz and 100 % amplitude, for 20s and 60s, leading to the same temperatures as above, respectively), in combination with Aspergillopepsins I (AP-I) supplementation (100 μg/L), was studied on unstable protein concentration (TLPs and chitinases) using HPLC with an UV–Vis detector in a TLPs-supplemented model system and in an unstable white wine. In model wine, neither temperature nor sonication affected TLPs concentration, suggesting their unfolding reversibility. However, the presence of AP-I during US treatment reduced protein concentration, up to complete removal under the most powerful conditions. In wine, the temperature effect was enough to lower chitinase levels (~48% and ~54% reduction at 40°C and 70°C, respectively) but had an undetectable effect on TLPs level. US significantly reduced both protein families, being more effective on chitinases (52% and 69% reduction at 20 s and 60 s, respectively) than TLPs (~11%) with the most powerful treatment. Interestingly, US was more successful than heating on chitinase (32%) and TLPs (15%) removal at the most energetic conditions. The supplement of AP-I combined with heating or US further reduced protein concentration. For heat treatment, both proteins were affected at both temperature conditions (TLPs: ~25% and ~23%; chitinases: ~58% and ~46%), while AP-I combined with US only affected TLPs under the most energetic treatment (~18%). The study found that US can affect unstable grape proteins and has additional mechanisms beyond sonication-induced temperature increase. When combined with AP-I, it further reduces unstable proteins, and suggests interaction between the US and AP-I. Further investigation is required to determine if US treatment destabilises proteins through a mechanism distinct from temperature increase, considering other factors affecting protein stability in winemaking conditions.

 

1. Celotti, E., Barahona, M. S. O., Bellantuono, E., Cardona, J., Roman, T., Nicolini, G., & Natolino, A. (2021). High-power ultrasound on the protein stability of white wines: Preliminary study of amplitude and sonication time. LWT, 147, 111602

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Adelaide Gallo1,2, Tomas Roman¹, Andrea Natolino³, Andrea Curioni4,5, Matteo Marangon4,5, Emilio Celotti³

1. Fondazione Edmund Mach—Technology Transfer Center, via Edmund Mach 1, 38050 San Michele all’ Adige, Italy
2. C3A – Università degli Studi di Trento, Via Mach, 1, 38010 San Michele all’Adige, Italy
3. Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, via Sondrio 2/A, 33100 Udine, Italy
4. Department of Agronomy, Food, Natural Resources Animals and Environment (DAFNAE), University of Padua, Viale dell’Uni-versità, 16, 35020 Legnaro, Italy
5. Interdepartmental Centre for Research in Viticulture and Enology (CIRVE), University of Padova, 31015 Conegliano, Italy

Contact the author*

Keywords

Ultrasound, Aspergillopepsins I, TLPs, Protein stability

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

EVALUATING WINEMAKING APPLICATIONS OF ULTRAFILTRATION TECHNOLOGY

Ultrafiltration is a process that fractionates mixtures using semipermeable membranes, primarily on the basis of molecular weight. Depending on the nominal molecular weight cut-off (MWCO) specifications of the membrane, smaller molecules pass through the membrane into the ‘permeate’, while larger molecules are retained and concentrated in the ‘retentate’. This study investigated applications of ultrafiltration technology for enhanced wine quality and profitability. The key objective was to establish to what extent ultrafiltration could be used to manage phenolic compounds (associated with astringency or bitterness) and proteins (associated with haze formation) in white wine.

Read More

OTA DEGRADATION BY BACTERIAL LACCASEST

Laccases from lactic acid bacteria (LAB) are described as multicopper oxidase enzymes with copper union sites. Among their applications, phenolic compounds’ oxidation and biogenic amines’ degradation, have been described. Besides, the role of LAB in the toxicity reduction of ochratoxin A (OTA) has been reported (Fuchs et al., 2008; Luz et al., 2018). Fungal laccases, but not bacterial laccases, have been screened for OTA and mycotoxins’ degradation (Loi et al., 2018). OTA is a mycotoxin produced by some fungal species, such as Penicillium and Aspergillus sp., which infect grape bunches used for winemaking.

Read More

ASSESSMENT OF GRAPE QUALITY THROUGH THE MONITORING OFPHENOLIC RIPENESS AND THE APPLICATION OF A NEW RAPID METHOD BASED ON RAMAN SPECTROSCOPY

The chemical composition of grape berries at harvest is one of the key aspects influencing wine quality and depends mainly on the ripeness level of grapes. Climate change affects this trait, unbalancing technological and phenolic ripeness, and this further raises the need for a fast determination of the grape maturity in order to quickly and efficiently determine the optimal time for harvesting. To this end, the characterization of variety-specific ripening curves and the development of new and rapid methods for determining grape ripeness are of key importance.

Read More

INCREASING PINOT NOIR COLOUR DENSITY THROUGH SEQUENTIAL INOCULATION OF FLOCCULENT COMMERCIAL WINE YEAST SPECIES

Vitis vinifera L. cv. Pinot noir can be challenging to manage in the winery as its thin skins require careful handling to ensure sufficient extraction of wine colour to promote colour stability during ageing.1 Literature has shown that fermentation with flocculent yeasts can increase red wine colour density.2 As consumers prefer greater colour density in red wines,3 the development of tools to increase colour density would be useful for the wine industry. This research explored the impact of interspecies sequential inoculation and co-flocculation of commercial yeast on Pinot noir wine colour.

Read More

CHARACTERIZATION OF THE AROMA PROFILE OF COMMERCIAL PROSECCO SPARKLING WINES

The typicality of a wine, as well as its aromatic identity, are attributes that are highly sought after and requested by the current market. It is therefore of considerable technological interest to investigate the aromatic aspects of specific wines and to identify the odorous substances involved.In this thesis work, the characterization of the aromatic composition of Prosecco wines available on the market with a price range between 7 and 13 euros was carried out. These wines came from three different areas of origin such as Valdobbiadene, Asolo and Treviso.

Read More