Hello everybody! Today, we are going to talk about temperature in fermentation or doing fermentation. And even though I am standing over a Syrah bin that is getting pumped over, I think everybody should know that temperature in fermentation really relates to basically every wine that you are making whether it is a Syrah or a Pinot Noir or a Cab or the white wines like Chardonnays or Sauvignon Blanc.
So, how important is temperature and how do we monitor it? And how do we actually keep it from either going too high or too low? Now, let us start with white wines, get those out of the way. With the white wines, whether you are making a very bright fruity kind of crisp style of wine versus something that has a little bit more weight or a little bit more density to it, temperature does play a key role. And that is why the grassy kind of spritsy, bright, sauvignon blanc tend to be fermented at that cool temperature or actually even cold anywhere between, I want to say 12 and 15 Degrees Celsius. You are looking at getting that style evolve from there because the cooler the fermentation, the more fruit forward the wine is going to be or if you are doing a barrel fermentation chardonnays, you are looking more for that 18 to 20 Degrees Celsius temperature. Because that slightly warmer temperature tends to enhance a little bit more of the weight of the wine and does not focus so much on the fruit intensity that the wine offers. That is white wine.
Now, let us go to red wine and to some extent, there is some similarities when it comes to temperature range for making a particular red wine. If you are making a very bright kind of light colored, very fruit driven Pinot Noir, you do not need to get that temperature up to about 32 to 33 Degrees Celsius, you can actually cap it on about 27 to 18. Because at that point, you really are accentuating the fruit component and kind of limiting the real deep color extraction that happens when you do ferment quite hot. Now, if you go for the more hardy robust reds like cabs, you kind of want to push the envelop when it comes to temperature, you do want to get up there around 33 to 34 degrees without necessarily going to over boil because you do run the risk of harming the yeast. They do have a tolerance level when it comes to high temperatures but you will get some real deep dark color extraction when you get that temperature up early in fermentation.
There is different times doing fermentation where you need to focus on getting that temperature up. And early on in fermentation is where you get all of that color extraction happening and that is where you want to focus on your temp. In my hand, I have a thermometer that we actually use to go around bins and actually monitor the temperature. And the reason I am pumping over this bin of Syrah is because it actually got the temperature. It was getting above 33 degrees. And when you get too warm where it can actually harm the yeast, you do need to circulate the wine so that you can aerate it and actually cool the temp down. Sticking the thermometer, we will find an area to go in there, I am actually seeing that we are able to take it down from 33 degree to 29 degrees. So it is probably getting a good aeration, it is getting the temperature lowered, so we are able to actually maintain the health of that fermentation.
A lot of people actually wonder how do you maintain temperature and control when it comes to fermenting your wines in bins? We do not have those shiny, stainless, sealed tanks here like the traditional wineries where they have temperature control through glycol. Here, everything is done in these one-ton tea bins and the way to control that temperature is by, one, doing this pump over like we are doing here. Two, we do have our cold room, which really serves a good purpose in terms of fermenting or cool our white wines in to that cold room so that it maintains that 15 Degrees Celsius temperature range. And then of course doing traditional punch downs, if you are not doing this up cap. If you got a Cabernet that you do not want to do sub cap for color extraction or for cap management but you are continuing to just do the standard punch down. That punch down itself actually helps cool that temperature down by actually mixing up the cap and the juice and actually bringing up the juice, doing the course of actually doing a punch down.
So in terms of monitoring, again, with the submersed cap, you can do the pump over. You can actually even take the sub cap out and do a punch down and then put the cap back in. If you have got a temperature that is really getting hot, another option is to actually move it in to the cold room and let the cap cool down and then punch the bend down while it is the cold room so that you can actually get the temperature gored by a good three to four Degrees Celsius. And again, if you are doing a white wine, whether it is a stainless steel fermented sauvignon blanc or chardonnays, most of the time, it is fermented in that cold room and a chardonnay that is barrel fermented a lot of times can actually be in our cellar, where you can get up to about 20 to 22 Degrees Celsius.
The yeast gets real happy when it has got all of the nutrients available to it so that it can consume all of the sugar and produce alcohol. But what a lot of people may not realize is that the alcoholic fermentation itself is an exothermic reaction. Hopefully, I am not using too big of a term for a lot of you folks out there. But exothermic meaning that is a reaction that actually releases heat and the stronger the yeast is, the more nutrient it has to feed on, the more active the fermentation is going to be which in turn then raises that temperature.
So it is very important to maintain consistency of temperature and actually having a healthy level of temperature where it is not harming the yeast. So by continually monitoring the temperatures on a daily basis, we are able to maintain the health of the yeast and be able to have a steady rate of fermentation. At the same token, if the temperature is too cold, you are going to have problems with the yeast actually doing their job too. So there is definitely a window where the yeast likes to function and give you the kind of wine that you want to make. And that is where the in-house wine makers and the cellar crew here that are working our Crushpad are making sure that everyone of these bins has the right proper temperature.
So now, to sum it all up, what kind of wine are we making and how is temperature going to be helping achieve that style of wine? If you are making a wine that you want to express a lot of bright fruit, that you want to show off a lot of nice red colors that are not completely dark and dense and brooding, then you can look at maximizing your temperature at about 25 Degrees or so Celsius. The deeper, the darker, the denser your wines are going to be. If you want to do something that is going to be really opaque in color, that is going to have a lot of inkiness to it. When the wine is young whether it is a Cab or Syrah or even a Zinfandel, then getting the temperatures up especially early on in fermentation, that is where you get a lot of that extraction happening.
So it is imperative to really look at getting the temperature up there if you want that style of wine. As far as whites are concerned, if you want to make a real crisp, bright, sauvignon blanc with a lot of vibrancy to it, a lot of freshness, you can actually then look at fermenting it quite cold. Again, in that 12 Degrees Celsius to 15 Degrees Celsius range. And if you want something a little bit more wavy, have a little creaminess and have some metalactic activity happen in that wine, you can actually look at getting the temperature up to about 18 Degrees Celsius to 20 Degrees Celsius.
So I hope that this brief little talk helped you guys out with how important temperature is during fermentation and I look forward to catching up with you with another edition of wine making.
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