 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

The representation of the vines: from symbol to spectacle

Landscapes such as its representation express values, beliefs and intentions of the individuals and the communities that produce them.

Nitrogen partitioning among vine organs as a consequence of cluster thinning

Agroscope is investigating the impact of yield on nitrogen (N) partitioning in grapevine and on must composition. The mechanism of N assimilation

Comparing different vineyard sampling densities and patterns for spatial interpolation of intrinsic water use efficiency

The need to rationalize agricultural inputs has recently increased interest in assessing vineyard variability in order to implement variable rate input applications, so-called ‘precision viticulture’. In many viticultural areas globally, precision viticulture is already widely used such as for selective harvesting and variable rate application (VRA) of inputs such as irrigation and/or fertilizer. Robust VRA relies on having a geostatistically accurate map (of one or more vineyard attributes) requiring high sampling densities, which can be cost- and time-prohibitive to obtain. Previous work on spatial interpolation using kriging have upscaled ground-based measurements, but such upscaling strategies are applicable only when vineyard conditions are spatially continuous and satisfies the assumption of second-order stationary processes. Alternatively, mixed models that combine kriging and auxiliary information, such as the regression kriging (RK) method, are more instructive for spatial predictions. In order to improve prediction accuracies, it is therefore necessary to incorporate additional information to achieve accurate spatial patterns with low error.

The impact of branched chain and aromatic amino acids on fermentation kinetics and aroma biosynthesis by wine yeast Saccharomyces cerevisiae

One of the major determinants of wine quality is the aroma. Wine aroma is the human perception of the matrix of grape and yeast derived volatiles and their interaction that contribute to flavour wine. Most common are higher alcohols, ester and aldehydes. In previous studies the formation of characteristic volatile compounds have been linked to the metabolism of branched-chain and aromatic amino acids
(BCAAs) in synthetic grape must. Here we report on an investigation to assess the impact of the initial amino acid concentration on the production of aroma compounds by the industrial yeast VIN13 grown in both synthetic and real grape musts.

Advancing wine authentication: non-invasive near-infrared spectroscopy and machine learning for vintage and quality traits assessment

Wine fraud, encompassing counterfeiting and adulteration, poses a significant threat to the wine industry, resulting in annual losses totalling billions of dollars.