terclim by ICS banner
IVES 9 IVES Conference Series 9 OIV 9 OIV 2024 9 Short communications - Oenology, methods of analysis 9 Direct SPME GC-MS determination of volatile congeners in wines without sample pre-treatment

Direct SPME GC-MS determination of volatile congeners in wines without sample pre-treatment

Abstract

In this study, the “Ethanol as an Internal Standard” method was employed for the SPME GC-MS quantification of volatile congeners in wines. This method is fast, cheap, and simple, as it requires no sample pre-treatment beyond dilution with water. A series of standard solutions containing 10 commonly encountered wine congeners was prepared gravimetrically to test the method’s linearity and sensitivity. The proposed method was then compared to the traditional internal standard (IS) method, using 1-pentanol as the IS compound. Although the precision and linearity for some compounds were slightly lower when using the proposed method, these issues can be mitigated through further optimization of the SPME methodology. In terms of accuracy, the proposed method exhibited similar recoveries to the traditional IS method. Ten real wine samples (five white and five red) produced in Austria were simultaneously analysed using both IS methods for comparison. The results showed that over 90% of the obtained data (mean concentrations of individual congeners from both IS methods) did not differ significantly (p=0.05). Given its significant advantages, the “Ethanol as an Internal Standard” method is recommended for routine wine analysis.

Direkte bestimmung flüchtiger verbindungen in wein ohne probenbehandlung

In dieser arbeit wurde die methode “ethanol als interner standard” zur spme-gc-ms-quantifizierung flüchtiger kongenere in weinen verwendet. Unser ziel war es, eine schnelle und einfache methode der weinanalyse ohne zusätzliche verfahren, reagenzien usw. Zu entwickeln. Eine reihe von standardlösungen, die einige häufig vorkommende kongenere im wein enthalten, wurde gravimetrisch vorbereitet. Die vorgeschlagene methode wurde mit der traditionellen methode des internen standards verglichen. 1-pentanol wurde als traditionelle is-verbindung verwendet. 10 echte weinproben (5 weiße und 5 rote) wurden mit beiden methoden analysiert, um sie zu vergleichen.  Es wurde festgestellt, dass das vorgeschlagene verfahren in der routinemäßigen weinanalyse eingesetzt werden kann. Probleme mit der linearität für einige verbindungen können durch zusätzliche optimierung der spme-experimentparameter gelöst werden. Hinsichtlich der metrologie wurde festgestellt, dass die vorgeschlagene methode eine ähnliche wiederholbarkeit und rückgewinnungsraten wie die traditionelle is-methode aufweist. Die nachweis- und bestimmungsgrenzen waren jedoch höher für die vorgeschlagene methode. Die analyse von weinproben ergab, dass 10% der erhaltenen ergebnisse (mittlere konzentrationen einzelner kongenere, die mit beiden is erhalten wurden) signifikant unterschiedlich waren (p = 0,05).

прямое определение летучих веществ в вине без пробоподготовки

В этой работе метод с использованием этанола в качестве внутреннего стандарта был использовандля определения летучих примесей в винах методом spme gc-ms. Нашей целью было созданиебыстрого и простого метода анализа вина без дополнительных процедур, реагентов и прочего. Сериястандартных образцов, содержащих некоторые часто встречаемые в винах примеси, былаприготовлена гравиметрически. Предложенный метод был сравнен с традиционным методомвнутреннего стандарта. 1-пентанол был использован как классический внутренний стандарт. 10 реальных образцов вина (5 белых и 5 красных) были измерены двумя методами в целях сравнения.  Было обнаружено, что предложенный метод может быть использован в рутинном анализе вина. Проблемы с линейностью для некоторых компонентов могут быть решены дополнительнойоптимизацией процесса экстракции. С точки зрения метрологии, предложенный методхарактеризуется схожей с традиционным методом повторяемостью и величинами извлечениядобавок. Однако, пределы обнаружения и определения у предложенного метода были нескольковыше. Анализ реальных образцов вина показал, что 10% полученных результатов (среднееконцентрациий индивидуальных аналитов полученных двумя методами внутреннего стандарта) имеют значимое отличие при уровне значимости p=0.05.

DOI:

Publication date: November 18, 2024

Issue: OIV 2024

Type: Article

Authors

Anton Korban¹, Goessler Walter², Radomir Čabala1

1 Faculty of Science of Charles University in Prague, Hlavova 2030/8, 128 00, Prague, Czech Republic
2 Faculty of Chemistry of University of Graz, Universitaetsplatz 1, 8010, Graz, Austria

Contact the author*

Tags

Full papers OIV 2024 | IVES Conference Series | OIV | OIV 2024

Citation

Related articles…

Acceptance of fungus-resistant grape varieties from the perspective of producers and consumers in Germany

Fungus-resistant grape varieties (frgv) are an important field of research in viticulture, as they represent a way of reducing the use of copper-containing pesticides and thus minimising the environmental impact. The literature suggests that resistant grape varieties are a promising solution to the problem of using copper-containing pesticides in viticulture and that their quality has improved in recent years. However, there are still challenges in the acceptance and dissemination of FRGV by wine producers and consumers.

Coping with heatwaves: management strategies for berry survival and vineyard resilience

Climate change is leading to an increase in average temperature and in the frequency and severity of heatwaves that is already significantly affecting grapevine phenology and berry composition (Webb et al., 2010). This is compounded by water stress, which is well known to increase the vulnerability of grapevines and berries to heatwaves. In hot climate regions like australia, grape production is only possible due to relatively secure supplies of water for irrigation. However, the upper temperature limits for berry survival of well-watered grapevines remains to be tested.

Applying value proposition design to collective strategic actions in family wineries: enhancing territorial resources in Vale dos Vinhedos, Brazil

The study aims to propose collective strategic actions for family wineries, promoting their competitiveness and the valorization of territorial resources.

Direct-injection HPLC for simultaneous determination of individual and total polyphenols in red wines: validation of the method

Polyphenols are very important compounds of red wines, serving as essential bioactive components and playing an important role in sensory properties. The determination of individual phenolic compounds in red wine is commonly performed by HPLC analysis, while the total polyphenols are quantified by spectrophotometric methods, usually by the method of absorbance at 280 nm (index of ribéreau-gayon) or the method of index of folin-ciocalteu. In this work, we pioneeringly proposed a new and fast method for simultaneous determination of individual and total polyphenols in red wines by direct-injection HPLC without sample preparation.

Inactivated yeasts: a case study for the future of precision enology

Yeasts serve as highly versatile tools in oenology. They do more than just perform alcoholic fermentation. Nowadays, yeasts from various species, naturally present in grapes, are selected for specific non-fermentative applications. For example, the use of selected non-saccharomyces at the early stage of winemaking has become a common practice to limit the growth of unwanted microorganisms. When inactivated, yeasts can be fractionated into soluble and insoluble fractions providing a wide range of benefits related to structural components or specific metabolites.