Analysis of Potent Odour-Active Volatile Thiols in Foods and Beverages with a Focus on Wine

Abstract

Certain volatile thiols are some of the most potent odour-active molecules that are found in nature. Thiols play significant roles in the aroma qualities of a range of foods and beverages, including wine, with extremely low odour detection thresholds (nanogram per litre range). A fundamental understanding of their formation, fate, and impact essentially depends on the development of suitable analytical methods. The analysis of volatile thiols in foods and beverages is a challenging task when considering (1) the complexity of food and beverage matrices and (2) that thiols are highly reactive, low molecular-weight volatiles that are generally present at trace to ultra-trace concentrations. For the past three decades, the analytical evaluation of volatile thiols has been intensively performed in various foods and beverages, and many novel techniques related to derivatisation, isolation, separation, and detection have been developed, particularly by wine researchers. This review aims to provide an up-to-date overview of the major analytical methodologies that are proposed for potent volatile thiol analysis in wine, foods, and other beverages. The analytical challenges for thiol analysis in foods and beverages are outlined, and the main analytical methods and recent advances in methodology are summarised and evaluated for their strengths and limitations. The key analytical aspects reviewed include derivatisation and sample preparation techniques, chromatographic separation, mass spectrometric detection, matrix effects, and quantitative analysis. In addition, future perspectives on volatile thiol research are also suggested.

An Approach of the Madeira Wine Chemistry

“…The volatile composition of wine has a significant role in wine quality as it contributes to several sensations during wine tasting. The odors (owing to compounds that can bind to olfactory receptors) can influence flavor (mixture of aroma and taste) in the mouth retro-nasally, which leads to consumer rejection or acceptance, and subsequently wine valorization [4,8,9]. Until now, more than 1000 VOCs with different polarities, volatilities, and in widespread concentrations (ng/L to mg/L) [10] have been identified in wines.…”

“…The volatile thiols, also called mercaptans, can cause defective aromas to wine quality, when present at a high concentration, as they possess the lowest OTs (ng/L or lower) [8]. The most common volatile thiols found in wines include 3-sulfanylhexan-1-ol (aroma descriptor: grapefruit; OT = 60 ng/L [50]), 3-sufanylhexyl acetate (aroma descriptor: passionfruit; OT = 4 ng/L [50]), and 4-methyl-4-sulfanylpentan-2-one (aroma descriptor: boxwood; OT = 0.8 ng/L [50]).…”

Physicochemical and aromatic characterization of carob macerates produced by different maceration conditions

“…Detection of aroma compounds is one of the most important steps in the evaluation of spirits, liqueurs, and other types of alcoholic beverages quality (Chen, Capone, & Jeffery, 2019). The aroma is influenced by many factors, including the quality of the starting raw material together with variables within the production process (Sliwinska, Wisniewska, Dymerski, Wardencki, & Namiesnik, 2015).…”

New Precursors to 3-Sulfanylhexan-1-ol? Investigating the Keto–Enol Tautomerism of 3-S-Glutathionylhexanal

“…Volatile thiol compounds, such as 4-methylsulfanylpentan-2-one (4MSP), 3-sulfanylhexan-1-ol (3SH), and 3-sulfanylhexylacetate (3SHA) are significant contributors to the sensory profile of white wines, including those produced from Vitis vinifera L. cv. Sauvignon Blanc, imparting characteristic grapefruit and passionfruit aromas [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. Despite the prominence of these odorants in the finished wines, these compounds are not found in appreciable levels in the grape berry or pressed juice and are produced almost exclusively during fermentation [ 8 , 9 ].…”