terclim by ICS banner
IVES 9 IVES Conference Series 9 DETERMINATION OF FREE AMINO ACIDS, AMINO ACID POTENTIAL AND PROTEASE ACTIVITY IN THE LEES AND STILL WINES OF CHAMPAGNE

DETERMINATION OF FREE AMINO ACIDS, AMINO ACID POTENTIAL AND PROTEASE ACTIVITY IN THE LEES AND STILL WINES OF CHAMPAGNE

Abstract

Prior to winemaking, organic or mineral nitrogen compound concentrations are usually measured in the vineyard and in grape musts. These indicators facilitate vine cultivation decisions, usually through yield or vigor. During vinification, yeast and bacteria metabolize nitrogen compounds in the musts in order to generate biomass. After fermentation, the microorganisms rerelease a part of this nitrogen as soluble compounds into the wines. Another part remains bound in the lees and can be lost during racking. The must’s natural nitrogen quantities, additional supplements during fermentation, and lees contact management enhance the release of nitrogen compounds to the wines. During ageing these nitrogen compounds – primarily the amino acids – are implicated in the generation of odorous compounds such as heterocycles(1).

Yeast cellular autolysis facilitates the diffusion of proteins and peptides into the wine. Associated with protease activity, amino acids can be released during ageing. The organic nitrogen content of wines and lees post-fermentation is not yet fully understood. This study explored the quantities of free amino acids, potential amino acids, and protease activity in champagne still wines and their corresponding lees. To achieve this analysis, a new quantification method to detect protease activity was developed using fluorescein isothiocyanate bound to a casein substrate.

In addition, the current method used to quantify potential amino acids after acid hydrolysis was optimized and associated to the previously published HPLC/FLD method for quantifying free amino acids(2). The methods were also adapted for quantifying lees. This analytical toolbox allows the observation of nitrogen compound kinetics over time, and was subsequently applied to sixteen young wines and their corresponding lees. The results of this study highlight a high variability in amino acid content between wines and lees. This suggests huge differences between amino acids levels in wine and in lees. No direct correlation was observed between lees quantity and the concentration of free and potential amino acids, indicating the mechanism is more complex. After 5 months of wine ageing with lees contact, the wines with lower levels of amino acids showed higher protease activity. That result encourages us to continue studying yeast lees and their variable capacities to release amino acids into wine over time.

 

1. Le Menn N, Marchand S, De Revel G, Demarville D, Laborde D, Marchal R. N,S,O-Heterocycles in Aged Champagne Reserve Wines and Correlation with Free Amino Acid Concentrations. J Agric Food Chem. 2017;65(11):2345-56.
2. Pripis-Nicolau L, De Revel G, Marchand S, Beloqui AA, Bertrand A. Automated HPLC method for the measurement of free amino acids including cysteine in musts and wines; first applications. J Sci Food Agric. 2001;81(8):731-8.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Nicolas Le Menn¹, Sera Goto1,2, Stéphanie Marchand¹

1. Université de Bordeaux, ISVV, EA 4577, INRA, USC 1366 OENOLOGIE, 33140 Villenave d’Ornon, France
2. Champagne Veuve Clicquot, 13 rue Albert Thomas, 51100 Reims, France

Contact the author*

Keywords

Nitrogen, relesable nitrogen, lees, ageing

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

WHAT’S FUTURE FOR SANTORINI’S VITICULTURE IN THE CONTEXT OF CLIMATE CHANGE

The own-rooted vineyard of Santorini is a unique case of vineyard worldwide that is been cultivated for thousands of years. On the island’s volcanic soil, the vines are still cultivated with traditional techniques, which are adapted to the specific and extreme weather conditions that prevail on it. While climate change is a reality in the Mediterranean region, will Santorini vineyard endure its impact? The study of the traditional training systems, techniques and vine density, as well as the application of sustainable solutions (cover crops and use of kaolin etc.) revealed sustainable methods for the adaptation of the local viticulture to new climatic phenomena that tend to be more and more frequent in the region due to climate change.

Read More

WINE AS AN EMOTIONAL AND AESTHETIC OBJECT: IMPACT OF EXPERTISE

Wine tasting has been shown to provide emotions to tasters (Coste et al. 2018). How will expertise impact this emotional response? Burnham and Skilleås (2012) reported that the cultural, experiential, and aesthetic competencies characterize an expert in wine compared to a novice. Although there is no consensual definition of an aesthetic experience, Burnham and Skilleås (2012) reported that aesthetic appreciation is “disinterested, normative for others and communicable” in comparison to sensory pleasure.

Read More

YEAST LEES OBTAINED AFTER STARMERELLA BACILLARIS FERMENTATION AS A SOURCE OF POTENTIAL COMPOUNDS TO IMPROVE SUSTAINABILITY IN WINE- MAKING

The yeast residue left over after wine-making, known as wine yeast lees, is a source of various compounds that are of interest for wine and food industry. In winemaking, yeast-derived glycocompounds and proteins represent an example of circular economy approach since they have been proven to reduce the need for bentonite and animal-based fining agents. This leads to a reduced environmental impact in the stabilization and fining processes in winemaking. (de Iseppi et al., 2020, 2021).

Read More

SIP and save the planet: a sensory and consumer exploration of australian wines made from potentially drought-tolerant white wine grapes

In order to attenuate the effects of climate change on the ability to cultivate quality wine grape vines in Australia, it is essential to adapt to the projected less favourable Australian climate scenarios. One response may be to convert a portion of the current grapevine plantings to those varieties that demand less water and can tolerate increased heat. This investigation aimed to (i) generate sensory profiles and (ii) obtain knowledge about Australian wine consumers’ preferences and opinions of Australian wines made from potentially drought tolerant, white wine grape varieties not traditionally cultivated in Australia. A Rate-All-That-Apply (RATA) sensory panel (n = 49) generated sensory profiles of 44 commercial white wines made from 7 different white grape varieties (Arinto, Fiano, Garganega, Greco, Verdejo, Verdelho and Vermentino), plus two benchmark examples each of an Australian Riesling, Pinot Gris and Chardonnay wine.

Read More

METHYL SALICYLATE, A COMPOUND INVOLVED IN BORDEAUX RED WINES PRODUCED WITHOUT SULFITES ADDITION

Sulfur dioxide (SO₂) is the most commonly used additive during winemaking to protect wine from oxidation and from microorganisms. Thus, since the 18th century, SO₂ was almost systematically present in wines. Recently, wines produced without any addition of SO₂ during all the winemaking process including bottling became more and more popular for consumers. A recent study dedicated to sensory characterization of Bordeaux red wines produced without added SO₂, revealed that such wines were perceived differently from similar wines produced with using SO₂ and were characterized by specific fruity aromas and coolness1,2.

Read More