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…

Using unmanned aerial vehicle with multispectral camara to efficiently and precisely monitor the incidence of downy mildew and technical maturity of beibinghong (vitis amurensis Rpru.) grapes 

Multispectral unmanned aerial vehicle (UAV) has been successfully applied in monitoring vine vegetative growth, however, there are still potential relationships between remote sensing vegetation indexes (vis) and vine condition or grape quality, so it is worthy a deeper investigation to make a better use of UAV. One of the purposes of the study is to find out vis that could denote the severity of downy mildew (DM), so that precise and differentiated control strategies would be adopted subsequently.

Does treatment of grape juice with aspergillopepsin-i influence wine aroma?

Acid aspergillopepsins-i (ap-i) have been suggested for use in winemaking due to their ability to degrade proteins, which reduces haze formation and the necessity for bentonite to achieve protein stability. These endopeptidases cleave non-terminal amino acid bonds of proteins, resulting in their degradation.

New ways of grape pomaces valorization: production of functional beverages or nutraceuticals

The wine industry generates each year 20 million tons of by-products. Among them grape pomaces represent a big part that can be considered as a source of potentially bioactive molecules such as polyphenols. Kombucha fermentation is an ancestral process which allow to increase the biological properties of tea by the action of a microbial consortium formed by yeasts and bacteria called scoby.

Social and environmental impacts of the adoption of a variety of table grape in the region of vale do São Francisco – Brazil

This study explores and analyzes the socio-environmental implications associated with the cultivation of the “brs-vitoria” table grape variety. Focusing on its adoption by farmers in the vale do submédio São Francisco region in Brazil, this study delves into the diverse impacts and changes brought about since its introduction, encompassing both the social and environmental dimensions of agricultural practices in the area. Embrapa, brazil’s federal agricultural research institution, encompasses a network of 43 thematic research centers spread across the nation.

Contribution of grape seeds to evolution of acetaldehyde, pigments and tannins reactive towards salivary proteins of red wine over time

This study investigated the impact of the gsk/gse ratio on the evolution of acetaldehyde and of major phenolic compounds of aglianico wine in wine like solution and real wine. Four model solutions and the correspondant control wines were prepared. The natural weight ratio between grape skins and seeds was determined on the real grapes, and a control wine was obtained from those.