Coffee/Mocha aroma research on Pinotage
Tuesday, 16 August, 2011
Wines of South Africa (WOSA)
In the past few years, prominent coffee/mocha flavours are being found
in certain styles of Pinotage wines. These emanate from a specific oak
regime used during the vinification process.
A letter published in the Sunday Times (South Africa) on the 7th of August 2011 refers to high levels of caffeine in Pinotage wines tested by a research team at the University of Pretoria
The first Pinotage wine of this style was produced by Bertus Fourie at Diemersfontein in 2001. Currently a lecturer at Elsenburg Agricultural College, Fourie explains that, from a technical point of view, the aromatics that give roasted coffee beans their aroma are also found in wine and are in fact a result of alcoholic fermentation in contact with toasted oak.
“The interesting fact is that although coffee or chocolate nuances are common descriptors of some wine aromatics, no other varietal emphasises the intensity as significantly as Pinotage. And of course a number of variables play a role – the ripeness, the type of yeast (and particularly its sulphur metabolism) and the type of oak, as well as the degree of toasting.”
The South African Department of Agriculture confirmed that where coffee flavours are derived naturally from the use of allowed oak products during vinification, the product is not in contravention of relevant South African and international wine legislation. The Department has been testing a range of Pinotage wines with pronounced coffee flavour profiles, using the liquid chromotography mass spectrometry method, and has not found any traces of caffeine. This is a dedicated and highly specific methodology for the detection of caffeine in wine, unlike the University of Pretoria’s small-scale study, which used a different methodology, designed to detect and identify wine aroma compounds. Caffeine was not a targeted analyte and different results could thus have been yielded.
In other words, the coffee aroma and caffeine will only have a relationship with each other if artificial products have been added to enhance the flavour, which the Department of Agriculture has not found to be the case.
This particular style of Pinotage wine has been hugely successful in certain export markets, as well as domestically, and seems to really appeal to consumers.