The tight-lipped school eschews any show of emotion, metaphor and simile. Michael Broadbent, possibly the leading authority on wine tasting and author of several books on the subject, maintains that "it is ridiculous to be over-expressive about quite ordinary wines". He is supported by the great Hugh Johnson, for whom the effusions of the florid school smack of bad English: "Some wines do not require that sort of imagery".

But the florid school is currently winning the day. Jilly Goolden is the doyenne. For her the restrained tasting notes of the past are 'a fat lot of use' when it comes to getting the taste of wine over to a wider public. She prefers to create 'taste pictures' with similes drawn from everyday life.

Her co-presenter on The Food Programme, Oz Clarke, believes the tight-lipped approach is a hang-over from the days when the wine trade was dominated by upper-class public schoolboys who had been brought up to distrust any display of emotion or enthusiasm. He is even happy that the many followers of The Food Programme 'take the piss' (his words) out of his and Jilly Goolden's approach.

We openly admit to being hedonic (as in 'hedonism', the search for pleasure) when we describe our malt whiskies. There is much to be enthusiastic about, and, as the Society's founder Pip Hills wrote in Scots on Scotch, the notes represent "...the joint subjectivity of our tasting panel". Nevertheless, our notes are worthless to you, dear member, if they bear little or no relation to what is actually there in the glass.

The Scientific Approach

Bearing this in mind, we were delighted to be able to help Colin Brown, a Manufacturing Scientist undertaking an Investigation by Analytical Chemistry of Compounds Affecting Flavour in Single Malt Whiskies, for Napier University, Edinburgh, with the support of United Distillers.

He writes:
"Single malt whiskies are chemically complex and are known to contain several hundreds of individual components (congeners) including a variety of alcohols, aldehydes, acids, esters and phenols, as well as carbonyl-, sulphur- and nitrogen-containing compounds. Many of these contribute to the flavour of a whisky and the relative concentrations of each are dependent upon variations in raw materials and production methods. Consequently, each single malt whisky is discernable from any other, including those produced at a neighbouring distillery."

The investigation, which is continuing, began by identifying the relative concentrations of compounds known to be extracted from the cask during maturation ('cask-extractive congeners') and a group of those which arise from the raw materials and during production ('volatile phenolic congeners'). It went on to make a correlation between these and the perceived flavour of the finished product.* Four samples of whisky were considered, affording a regional spread. They were: Caol Ila (Islay), Scapa (Orkney), Rosebank (Lowland) and Balvenie (Speyside). "Cask-extractive congeners are of great importance to the overall flavour as well as the aroma and colour of the finished beverage. Whisky casks are traditionaly treated to thermally degrade the internal surface of the cask, by firing and charring, for three major reasons:

• to generate a layer of active carbon which removes undesirable flavour substances;
• to effect the release and dissolution of flavour compounds such as vanillin during maturation;
• to yeild colour and phenolic substances which result in new flavour compounds by oxidative interactive reactions.

The results revealed that all four samples contained similar levels of the compound furfural, which is associated with a general 'whisky flavour'. The unmistakably woody flavour in the Scapa sample is attributable to syringealdehyde, which is also present in Caol Ila, although the dominating flavours of the Islay whisky are discussed later. The Balvenie chromatogram reveals a high level of ellagic acid, a compound known for its pungent odour and flavour. The number and relatively large abundance of lignin degradation products in the Caol Ila sample would suggest that a heavily charred oak cask was used for the maturation process. The presence of 5-hydroxymethyl furfural in Caol Ila would allow the taster to expect a slightly reddish tint to the whisky.

"Volatile phenolic congeners' primary source is from the peated malt used in whisky production. So it was not surprising to discover that the Caol Ila sample had a large number present and in concentrations greatly in excess of the other whiskies under investigation.

"The presence of phenol at 2.1 parts per million (ppm), was almost five times that for Rosebank, 20 times that for Balvenie and 200 times greater than that found in Scapa. Phenol has a medicinal taste and therefore would be expected to be present in an Islay whisky. Guaiacol, known for its smoky and phenolic flavour, was detected in concentrations of 1.2 ppm in Caol Ila, but was barely detectable in the others. Further investigation showed that the levels of compounds responsible for 'tarry' and 'disinfectant' flavours (m-, p- and o-cresol) were evident in the Islay sample but relatively low in Rosebank, very low in Balvenie and not detectable in Scapa. However, similar concentrations of the compound eugenol (perceived as having a flavour not dissimilar to that of cloves) were determined in both Scapa and Caol Ila. All of the whiskies investigated contained varying concentrations of 4-ethyl phenol and 2,5-xylenol, which co-eluted and could not be determined separately. Both of these substances have a powerful 'whisky' flavour."

Mr Brown concludes:

"Many other compounds were determined analytically during this investigation, however their individual impact on flavour is considered less important than their contribution to the overall flavour of each whisky. These analyses are intended to give an insight into the complex chemistry of single malt whiskies and the impact which each of the many hundereds of compounds has on the characteristics of the finished product."

With respect to chemists - and subject, of course, to your comments - I think we will stick to hedonic descriptions!

*For those of you who understand the lingo, the compounds were determined by the use of a 'direct-injection reversed-phase High Performance Liquid Chromatographic technique (HPLC), employing gradient elution and either uv/vis (diode array) detection or fluorescence'.

Charlie Maclean