22 December 2011

Let ML's begin

Yes folks, it's that time of year again.  I've started tracking MLs on the Pinot noir using paper chromotography.  I haven't inoculated the Chardonnay or the Rosé yet, still waiting for the fermentations to finish is all the barrels, but I did get on the Pinot noir.  As a refresher, ML stands for malo-lactic, and is the secondary fermentation that wine can go through.  Not all wines go through ML though generally wines aged in barrels do.  Wine in stainless steel tanks can also go through ML but it seems to be less common.  Instead of a yeast fermentation, like primary fermentation, which converts the sugar to alcohol, this is a bacteria which converts malic acid, like that found in green apples, to lactic acid, found in milk.  The change in the type of acid causes a pH shift which combined with the different acid makes the wine taste softer and rounder.  Which is why winemakers have wine go through in ML.  This year the wines seem to have very high levels of malic acid and I am expecting to see a larger pH shift than normal.  We'll see if that is true.  After checking to see if the barrels had started on their own, they hadn't, I decided to inoculate. 
The ML bacteria comes freeze-dried and I allow it the rehydrate in water for 15 minutes before adding it to barrel, you can see it sitting in the plastic container in the upper right corner of the picture below.  I also add nutrients specific for the bacteria to each barrel which is the powder sitting on the scale.   Healthy bacteria combined with the right nutrients and a warm enough barrel room will hopefully get the fermentation off to a strong start and I'll soon be able to see activity in the barrels.  I enjoy checking on the wines while they are going through ML because the wine seems to sparkle and swirl all on its own when the bacteria is going strong.  I'll inoculate the Chardonnay and Rosé as soon as they are finished with primary fermentation, it is rumored that you can have both going at the same time but I've not had much luck with that so I prefer make sure the primary fermentation is done before trying to start the secondary.
As for primary fermentations, my reinoculated Pinot gris seems to be going, not very quickly and I have to warm it just about every other day but it's moving, i.e. the sugar is dropping, and that makes me happy.  The rest of the whites in the winery are finished and I'm just waiting on this last tank of Pinot gris to start blending trials for Seven.  I also need to start checking the wines for protein stability and cold stability.  I can't wait to get started!

No comments:

Post a Comment