Taint, Mould, Sweet-Sour, Elastoplast, Stale Honey, Bee Wax and Potato Skin With the Wine Prof
Education Experience 4.0 Wine Courses

Taint, Mould, Sweet-Sour, Elastoplast, Stale Honey, Bee Wax and Potato Skin With the Wine Prof

Wednesday 30 August 2017

Experience: 4/5

There was no easy route from the Southern Suburbs, Cape Town to the Cape Wine Academy offices in North-East Stellenbosch for a 6pm start. I left plenty of time as I had not been to the venue before and yet I was one of the last to arrive. There was an unexplained hush among the 20 or so students in the classroom. I never got the chance for introductions and so perhaps they were eager learners in awe of their Professor.

Lecturer Dr Wessel du Toit, Associate Professor at the Department of Viticulture and Oenology, Stellenbosch University, was anything but imposing. Chatty and with humour, he guided us through the characteristics and chemistry of faulty wines. I soon learned that faulty and spoiled wines are not the same. ‘Faulty’ wines are not always spoiled. How does that make sense?! A faulty wine is one with a definite fault which lowers the quality or makes the wine undrinkable. A spoiled wine, in the other hand – pun intended – is one that has been tainted or is undrinkable by certain micro-organisms.

The first half of the lecture was theory, the second practice. Wine faults are logically classified into those that can be seen (clarity and colour), smelt (off flavours) or tasted (bitterness). We can detect 5 or 6 taste sensations but several hundred aromas and so most faults are detected on the nose. Dr du Toit explained the different characteristics, causes and methods of prevention for cloudy wines, those with crystals and other hazes. I have rarely seen hazy wines in recent experience but have occasionally seen crystals in the bottom of a glass of white wine.

I have occasionally too detected volatile acidity (VA) caused by poor bacteria or yeast. The risk of VA is the reason why winemaking using natural yeasts is so risky. Brettanomyces, commonly known as ‘brett’, is rare too. It reduces fruitiness and wine complexity and brings distinct medicinal/elastoplast or rancid barnyard/horse sweat aromas to a faulty wine. Cork taint, that gives wine a metallic earthy, mouldy, mushroom or damp cardboard nose, is decreasingly common due to a combination of better winemaking, improved treatment of natural cork, synthetic corks and screw-caps. We learned too the difference between wines with oxidation and those that are over-aged. As for bitter tasting wines, Pinotage used to be susceptible. I learned that our sensitivity differs widely. This can range from allergy to ‘super taster’.

Theory over and it was time to smell and taste the major wine faults that had been reproduced with ‘spiked’ wines. We sampled white wines with mouldy TCA, the chemical and burning after-taste of over ageing, burnt rubber aromas from H2S, and with a sherry/nutty nose that is symptomatic of oxidisation. Red wine faults that were shown included medicinal ‘brett’, acetone/nail polish remover VA, mouldy potato oxidisation and dry, flat, plumy over ageing.


We ended with some ‘nice wines to taste’ as Dr du Toit informed. These were 2 wines made by Stellenbosch University: a fruity 2016 Die Laan Chenin Blanc (R55) and a plum 2015 Die Laan Pinotage (R75). It was good to return home with a pleasant wine taste in my mouth!

The course (excellent value at R420) gave me all the learning I wanted and all that a passionate wine enthusiast needs to know. The chemistry was sufficient and of interest to explain the underlying processes that make wine faulty. I had some pre-learning having completed (and passed) the Certificate in Wine Evaluation Short Course in June, also provided by the Viticulture and Oenology Department of Stellenbosch University. The Faulty Wine Course did what the Evaluation Course did not – and that was to be guided to see, smell and taste the common wine faults. I would advise anyone who wishes to learn more about faulty wines to do the Cape Wine Academy course first and then, if you wish to consider a hobby or career in wine evaluation or judging, to do the Short Course after.

I hope to continue my studies with Dr Wessel du Toit in future. He runs a 2½ day garagiste course twice a year. Regrettably, I had to cancel my course booking later this month as the dates clashed with my Cape Wine Academy Diploma training. Meanwhile, I shall follow Dr du Toit on Face Book. He must have one of the coolest profile names ever: TheWineProf!

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