Seasonal influences on whisky destilling?
as an advanced novice I quite enjoy the postings in this BB and would like to contribute by following up on Eriks advice to Iain on the vintage subject.
I guess this is about vintage taken a level further.
To answer your question about temperature and weather, Iain, I tried to find an answer in some books and found the following:
Charles MacLean mentions in 'Malt Whisky' that water temperature is crucial (for the cooling of the production process) but adds in the same sentance that most destillers cool the water anyway. He mentions further that destillers are able to determine whether a whisky was destilled in spring or autumn. Winter destilled whisky appears to be the best. He suspects the temperatue difference between the environment and the still: the higher the environment temperature, the higher the chance that unwanted elements pass through the still.
Graham Moore in 'Malt Whisky' mentions the change in water quality: the chemical make-up of water changes with the ambient temperature, with the quality falling as temperature rises. According to GM this is the reason why some destilleries close in summer.
Walter Schobert (Das Whisky Lexikon) and Thierry Bénitah (Whisky) only mention that there should be a lot of water available (that's why some destilleries close in summer) and that it should be cold, but they both don't reveal the reason.
Of course we know of the foreshots and feints being returned to the low wines/feints receiver but Philip Hills' in 'Appreciating Whisky' wonders about the possible influence this has on the taste of whisky if this happens over and over again. Furthermore, PH tells about the receiver that is opened and cleaned once a year. Its walls are coated with a dark waxy oily substance that might contibute to flavour...
I could not find any more in other publications, not even in , so, who could fill the gap here?
But now to the practical side, this seems more important yet even more difficult to determine: what does the time of destillation do to the taste of whisky?
I spoke to a bottler once, who stated that sampling casks with successive casks numbers revealed huge differences in taste and quality....
If we (the consumers) want to compare, we have to do it with commercial bottlings available, I guess, so:
adogranonthepitch mentions The Provenance with season bottlings. As for Port Ellen, the 18y winter bottling is aged in sherry cask, and the 19y looks like plain oak (bourbon?) to me. So we can't compare the seasonal influance with these.
Since most Independants except for G&M and Scott's state the month and year of destilling/bottling, has anyone noticed any seasonal differences?