 IVES 9 IVES Conference Series 9 Wine archeochemistry: a multiplatform analytical approach to chemically profile shipwreck wines

Wine archeochemistry: a multiplatform analytical approach to chemically profile shipwreck wines

Abstract

AIM: The Cape of Storms (also known as Cape of Good Hope) is renowned for harbouring a multitude of shipwrecks due to the inherent treacherous coastline and blistering storms. One such shipwreck is the English East Indiaman Colebrooke, wrecked in False Bay, South Africa, in 1778. A discovery on the shipwreck was a shipment of wine of unknown origin and style, possibly Madeira as it was known that the English East India Company often purchased wine from there but this was not mentioned in the ship’s log. As the wreck was exploited by treasure hunters, very little contextual information is known. To further expand the sample pool with more examples of old wine, we have included another sample recovered from the wreck of the SS Maori sunk in 1909. Additionally, three samples of (old) wines stored in vinotheque conditions were included: a Château d’Yquem (1918 vintage) and two Château Margaux (1984).

METHODS: A minimal volume of wine (<50 mL) was analysed using untargeted analyses (GC-MS, LC-HRMS and NMR spectroscopy), metals (ICP-MS/OES), and sugars and organic acids (HPLC-DAD-RID). Important volatile aroma compounds were identified by HS-SPME-GCMS and their identification confirmed using Wiley/NIST libraries and RI. A screening exercise was performed by experienced researchers to sensorially evaluate the possible wine-like aromas.

RESULTS: Unexpected chemical characteristics regarding the metal concentrations, sugar and acid composition as well as the aroma profile were found. Compared to current export regulations, the levels of heavy metals were considerably higher, possibly due to the bottle glass composition and leaching over time. The untargeted analyses showed various compounds including fermentation-derived products (esters, alcohols, aldehydes and fatty acids), terpenoids (linalool, fenchone) and “woody” compounds (furfural and guaiacol). Incredibly, some of the samples still presented wine-like features related to aroma both in the chemical and the sensory evaluation.

CONCLUSIONS

Unlike other work where the source and/or type of beverage recovered from shipwrecks were known, and with a limited volume of sample, we could still obtain results providing interesting “chemical snapshots” of old wines using advanced analytical and spectroscopic techniques. Combining new technology platforms in analytical chemistry can provide valuable insight into the composition of wines recovered from shipwrecks with the help of maritime archaeologists. Including analyses such as X-ray diffraction on the bottles can assist in tracing more information about the sources of heavy metal content and possibly even the origin of the wines.

DOI:

Publication date: September 13, 2021

Issue: Macrowine 2021

Type: Article

Authors

Astrid Buica

South African Grape and Wine Research Institute, Department of Viticulture and Oenology, Stellenbosch University, South Africa,Cody, WILLIAMS, Department of Viticulture and Oenology, Stellenbosch University, South Africa Jaco, BOSHOFF, Iziko Museums of South Africa, Maritime Archaeology Unit, Research and Exhibitions, Cape Town, South Africa Wendy, BLACK, Iziko Museums of South Africa, Archaeology Unit, Research & Exhibitions Department, Cape Town, South Africa Valeria, PANZERI, Department of Viticulture and Oenology, Stellenbosch University, South Africa

Contact the author

Keywords

marine archeology, shipwreck, untargeted analyses, metals, sugars and organic acids, sensory screening

Citation

Mesoclimate and Topography influence on grape composition and yield in the AOC Priorat

The Priorat AOC, which is situated behind the coastal mountain range of Tarragona, is characterised by a Mediterranean climate that tends towards continentality and has very little precipitation during the vegetation cycle

Key genes in rotundone biosynthesis are affected by temperature, light, water supply, and nitrogen uptake

Rotundone accumulation and biosynthesis is a complicated process. Previous research highlighted that these phenomenons were affected under ecophysiological conditions by viticultural practices (e.g. defoliation or irrigation). Individually, these practices often impact several abiotic factors that are difficult to separate such as temperature, water or nitrogen status, or radiation. Such dissociation can be achieved under controlled environmental conditions using potted vines.

‘TROPICAL’ POLYFUNCTIONAL THIOLS AND THEIR ROLE IN AUSTRALIAN RED WINES

Following anecdotal evidence of unwanted ‘tropical’ character in red wines resulting from vineyard interventions and a subsequent yeast trial observing higher ‘red fruit’ character correlated with higher thiol concentrations, the role of polyfunctional thiols in commercial Australian red wines was investigated.
First, trials into the known tropical thiol modulation technique of foliar applications of sulfur and urea were conducted in parallel on Chardonnay and Shiraz.1 The Chardonnay wines showed expected results with elevated concentrations of 3-sulfanylhexanol (3-SH) and 3-sulfanylhexyl acetate (3-SHA), whereas the Shiraz wines lacked 3-SHA. Furthermore, the Shiraz wines were described as ‘drain’ (known as ‘reductive’ aroma character) during sensory evaluation although they did not contain thiols traditionally associated with ‘reductive’ thiols (H2S, methanethiol etc.).

Effect of irrigation and soil type on root growth and distribution of Vitis vinifera L. cv. Nero d’Avola grown in Sicily

L’essai a été effectué dans un vignoble du cépage Nero d’Avola greffé sur 1103 Paulsen dans un terroir de la D.O.C Alcamo en Sicile. Le système de conduite des vignes était à espalier, la taille à cordon coursonné et l’irrigation à goutte a goutte. On a été confrontés trois types de traitements: A) vignes non irriguées; B) vignes irriguées quand le

Targeted and untargeted 1H-NMR analysis for sparkling wine’s authenticity

Studies on wineomics (wine’s metabolome) have increased considerably over the last two decades. Wine results from many environmental, human and biological factors leading to a specific metabolome for each terroir. NMR metabolomics is a particularly effective tool for studying the metabolome since it allows the rapid and simultaneous detection of major compounds from several chemical families.1 Quantitative NMR has already proven its effectiveness in monitoring the authenticity of still wines.