Yeasts of the southern wild

It’s been a week since I posted last, but harvest has been so hectic that I haven’t had a chance to sit with my computer and write. It’s been 13-16 hour days with a couple 4 am starts, so both my mind and body have been prioritising sleep over blogging. Nevertheless, since then we started fermenting so many tanks of must by adding yeast to them (the actual ‘wine’-making part) I thought I’d write a bit about the topic.

Yeasts are magic. They are the ones responsible fermenting what is essentially just grape juice into an even more delicious alcoholic beverage that people buy to celebrate or unwind with,  to drink when they’re happy, sad or fighting global wars (like Madame Taittinger and Churchill respectively) and generally obsess over.

Reading about wine-making before, I never really gave much thought about yeast. I didn’t realise just how many types of yeasts there are. There are yeasts for all occasions and wine styles, bred by companies to suit any type of need -slow, fast, hot, and cool fermentations, and ones that impart certain flavours to the final wine.

What’s interesting about it is that although it seems quite complex, the process of adding yeast to must to make wine is very similar to that when you prep it for baking bread. It actually looks and smells the same – miniscule sandy-coloured pellets when dry with a bready and beer-like aroma. To proof it for a vat of wine, you add hot water to a bit of grape juice to get it going. Warmed up and active, they start bubbling away quickly and create a nice warm foam floating on top of the juice that you have to stir around with your hand. Laura took quite a fancy to this, and it does feel pretty nice, although your hands smell like yeast for the rest of the day.

For white wines, before fermenting with yeast, you crush the must, press it to remove the juice from the skins and grape solids. Then you settle it so any remaining solids float down on the bottom of the vat and can be removed before adding the yeast so essentially you ferment it as a clear juice. You make up the yeast separately in a bucket and climb a ladder to pour it into the vat from the lid on the top.

A yeast culture for white wine that just started proofing, and then the same yeast 5 mins later

For reds, you actually crush the grapes and leave them in a vat with the berries and skins and then add the yeast to ferment. This helps extract colour and flavour from the skins, so that the juice has all that lovely red wine aroma and tannin that comes from the skins. Adding red wine juice to the yeast to activate it makes it looks a bit like strawberry yoghurt! At Jordan, we add the yeast when the red must is being pumped over, which is basically circulating it by drawing it off the bottom of the vat and pumping it over to the top so it sprays down and mixes again with the must. It’s a messy business, and you get splattered with red wine droplets all over any exposed parts of your body. Red juice beauty spots are a common sight amongst the team.

 

 

 

Red wine yeast-making, pouring juice into the yeast to 'feed it' during proofing, and Mike watching over a pump over process for Merlot

 

Apologies for the fuzzy pictures. Took them on my old iPhone in the cellar as having a camera around is a bit risky with all the juice droplets flying around!