Key to sweet wines: 

– The fruit must be physiologically ripe prior to botrytised infection.  What I am looking for is 21-24 brix, apricot/mandarin/lemon blossom aromas, acidity

– Need vintage conditions and site to allow slow ripening whilst retaining high natural acidity and low pH.  Why? – acid/fruit sweetness balance in the mouth – avoid that sugary/cloying character of warmer climate sweet wines and/or the need for massive additions of tartaric acid which can be detected as harsh on the palate.  Marlborough’s vintage climate and cool nights are ideally suited to achieve this acid/pH balance.

– Botrytise; ideally a late warm rainy infection of this fungus followed by drying conditions is ideal.  But that’s not always what nature deals up to us, so we can manipulate conditions a little to help her ... I will say no more!!

– My old girls, some of whom have worked for me for 20 years.  They know what to pick and when.  If you think that’s not important, then you’ll struggle to make great sweet wine.  Maybe its because they are so sick of my annual pep-talk that they get on and do it before I have a chance to give it!

– Making wine from grapes heavenly infected with the ”noble – rot” is not without its challenges.  The first of which to achieve maximum extraction of the lovely honeyed toffee botrytise flavours whilst retaining the fresh citrus aroma of ripe Riesling.  That done the juice with its very high solids content, from long pressing, is always difficult to clarify to allow the best fermentation of clear juice.  Fermentation itself can be difficult – yeasts don’t like living in that higher sugar solution – who would? Not to mention the presence of some exotic toxins from the botryise fungus.  All of which can make the fermentation yeasts struggle which may lead to excess production of volatile acids, (stale tomato sauce aroma) in the final wine – lovely!
So next time you enjoy a great Trockenbeerenauslese, $100 - $200/ 375 ml bottle, I hope you may appreciate what a bargain you’re getting at $40/ 375 ml from Forrest.

January 2011