To gris, or not to gris

Pinot gris and pinot grigio - different styles of white wine made from the same grape - have emerged as a significant part of the wine market but many drinkers are confused about their identity.

Gris is a richer, fuller-bodied wine made from riper grapes and often with a touch of sweetness. It's based on the pinot gris of Alsace, France. Grigio, based on a style of wine made in northern Italy, is lighter, crisper, drier and less complex. It is made from earlier-harvested grapes, which naturally make lower-alcohol wine.

Needless to say, they are suited to different foods - imagine a crisp dry white with oysters, or a fuller, softer white with stuffed and roasted chicken - and it would make sense if gris and grigio had labels indicating their properties.

Well, help is at hand in the form of a scale that will begin to appear on some wine bottles.

Called the Pinot G Style Spectrum, the scale was devised by the Australian Wine Research Institute in co-operation with the idea's prime mover, winemaker Kevin McCarthy of T'Gallant winery on the Mornington Peninsula. T'Gallant was an Australian pioneer of pinot gris/grigio in the early 1990s and is still a leading producer.

Why involve such a busy and rarefied organisation such as the AWRI in what seems like a pretty simple exercise?

Well, McCarthy wanted to do it properly and he wanted the scale to have a scientific basis.

Unveiling the spectrum in Sydney, the AWRI's Peter Godden says McCarthy phoned him one day and asked: "Can the AWRI do some analysis which would define the difference between gris and grigio?" About three years and a lot of money later, the partners launched the initiative last Friday.

The Pinot G Style Spectrum relies on spectral analysis to determine the constituents of wines. By shining lights through a fluid you can discover what's in it, from the light that's absorbed and the light that isn't.

To set up profiles for pinot gris and grigio, the AWRI analysed a number of wines, measuring the main components such as alcohols, acids, sugars and phenolic compounds, which are mostly tannins. To check their results they used human tasting panels. They were in close agreement with the spectral analysis so the system proved accurate and helpful.

To demonstrate how tasting correlates with analysis, a group of professionals - mainly sommeliers and myself - did a simple blind tasting of six pinot gris/grigios. We were asked to place each wine on a nine-point continuum from crisp at one end to luscious at the other. When the wines were revealed, we found most of us placed the wines precisely where the analysis put them. That is, the grigios were clustered at the crisp end (between 3.5 and 4.5 on the scale of nine) and the gris at the luscious end (between 6.5 and seven). There was a distinct gap between the groups.

T'Gallant Grace, Rosemount and Seppelt (all labelled grigio) were in the crisp half of the scale, while T'Gallant Tribute, T'Gallant Imogen and Secret Stone (all labelled gris) were in the luscious half. T'Gallant Tribute, which weighs in at an astonishing 15.8 per cent alcohol, was at the extreme point of luscious - at least on my notepad. But of course, it's not only alcohol that determines gris style.

Age has a subtle influence on how a wine rates. The wines we tasted were all 2008s except the '07 Secret Stone. "As wines age, they move up the scale of lusciousness slightly - say one point per year," Godden says.

What about sweetness? Both styles, especially gris, can vary widely. So, does the analysis accommodate differences in residual sugar?

The answer is, somewhat disappointingly, no. "Ten grams per litre is the sweetness limit for this analysis," Godden says. That would cut out a lot of the richest Alsace gris and many of the more commercial New Zealand versions. "It's still in the development phase," McCarthy says.

However, the two men believe the scale will be very useful in Alsace and Italy as well as the Antipodes. Godden expects several hundred thousand bottles wearing the Pinot G Style Spectrum label will be on the market this year. It just remains for wineries to send samples to the AWRI for grading.

The spectrum bears the AWRI logo. It's the first time the institute has been involved in such a commercially-applied project.

Interestingly, in future, the AWRI will be able to spectrally analyse wines without opening the bottles. It will simply shine lights through the glass. This will greatly reduce the time taken and the cost of analysis.

So, the bottom line is this: tasters agree on what constitutes a gris versus a grigio. But, can this be communicated? "Probably - with a considered and consistent marketing approach," McCarthy says. "In future, I imagine people will walk into a shop and say, 'I'd like a PG at three on the scale, please'. Before now we never had an objective scale to describe wine. It's a whole new language."