Fredrik L wrote:Andrew Burge wrote:On petrol in riesling, I have heard (third hand) that John Vickery, Australian riesling guru responsible for the Leo Buring wines of the 1970's, believes the petrol character comes from grapes getting excessive direct sun exposure. Andrew
A belief confirmed by research studies, notably Marais et al in 1992.
Marais, J., Van Wyk, C.J. & Rapp, A., 1992a. Effect of sunlight and shade on
norisoprenoid levels in maturing Weisser Riesling and Chenin blanc grapes and
Weisser Riesling wines. S. Afr. J. Enol. Vitic. 13, 23-32.
Greetings / Fredrik L
Fredrick,
That is the very source 'Jane' quoted.
Jane, 09-Mar-2002 from old WLDG wrote:J. Marais, C.J. van Wyk and A. Rapp, Effect of sunlight and shade on norisoprenoid levels in maturing Weisser Riesling and Chenin Blanc grapes and Weisser Riesling wines, S. Afr. J. Enol. Vitic., 13 (1992) 23-32.
This study was done on both wine and grapes. Within the same journal (same reference) is another study concentrating on the effects of storage time, temp and region on TDN. pgs 33-44.
I'm gonna put out an APB to other contributors to that old thread.