When to press & initial headspace

[Vinoors]

Hi everyone,

Question 1: How long do you wait before pressing your grapes?

We've blindly waited between 5 & 7 days in the past and then pressed (using native wild yeast every year). However, I came across something recently that stated you should wait until your Brix is 0º before pressing(possibly either a morewine manual or the winemakers answer book by Alison Crowe....can't recall exactly, but it was a reputable source). This coming year will be the 1st where I will use a refractometer. In thinking about prior years, whenever we move the must to the press there is still a great deal of fermentation going on, so we typically leave significant headspace when funneling wine into vessels so as to avoid any blow off and then top off in about a week or so. Which leads me to....

Question 2: When initially filling your vessels after pressing do you immediately eliminate all headspace?

Assuming that you wait until the brix is 0º from the maceration, then I suspect there is no need to allow headspace, since any vigorous fermentation has already been completed and there is no CO2 production to fill the gap.

I've attached an image from 2016 in order to give you an idea of the fermentation vigor post the press and the amount of headspace we leave.

I'm not interested in extended maceration/cold soaking, etc. just looking for standard protocol (if there is one).

 

[sour_grapes]

This coming year will be the 1st where I will use a refractometer.

I don't know the answer to your winemaking questions, but I caution you that you cannot (easily) use a refractometer to tell when your fermentation is completed. The alcohol in the wine affects the index of refraction.

I think it would be easiest to use a hydrometer. However, if you want to use a refractometer anyway, here is a page that should help: http://valleyvintner.com/Refrac_Hydro/Refract_Hydro.htm

 

[Ajmassa]

I think pressing at 0° Brix still leaves enough fermentation going on to not worry about headspace yet. At least a couple weeks. After racking the massive amount of lees a few days after press and then another rack a couple weeks later. Worked for me at least. And I have seen it work that way even over a much longer time period. (Though You have more headspace than what I've seen in what I mentioned)

 

[salcoco]

if using a refractometer fermentation ending number is anywhere from 5-8 brix depending on starting sg. download the spreadsheet and fool around with some numbers and you will see that 0 brix is difficult to attain on refractometer because of alcohol . the vessels shown in the picture are adequately filled as some fermentation will occur once pressing is done and head space required for any foaming. head space issues are after clearing.

 

[Johnd]

I'll second the several suggestions of caution when using a refractometer to evaluate the fermentation progress, in my opinion, a hydrometer is easier and more appropriate. I use my refractometer prior to the beginning of fermentation, but not after.

Having said that, my typical process is to ferment down to somewhere around 1.000, maybe a tad lower or higher, depending upon my ability to actually press. Once pressed and the wine is in vessels, a reasonable amount of air space is essential, as you recognized, to prevent overflows, etc., and the remaining fermentation produces sufficient CO2 to protect your wine.

2 -3 days after pressing, fermentation is typically slowing substantially, and the wine is racked to rid it of much of the gross lees, and the vessels are filled higher than before, eliminating a lot of air space, but not completely topped off.

After a couple of weeks, AF is completely over, and MLF is progressing, my wine will get racked again and topped off to appropriate levels until the end of MLF.

 

[Vinoors]

Thanks for all of the input. Not to start another whole topic- but I had a question about dry ice. How do you typically keep your fermentation temps down? I searched youtube for something like "wine dry ice" and I came across videos of actual wineries adding dry ice directly into their must to cool it down. When I search for "dry ice" on this site, nothing came up. Does anyone have any input on adding dry ice directly to their must? If dry ice is just frozen CO2, then maybe there is no harm in doing so?

 

[Johnd]

Thanks for all of the input. Not to start another whole topic- but I had a question about dry ice. How do you typically keep your fermentation temps down? I searched youtube for something like "wine dry ice" and I came across videos of actual wineries adding dry ice directly into their must to cool it down. When I search for "dry ice" on this site, nothing came up. Does anyone have any input on adding dry ice directly to their must? If dry ice is just frozen CO2, then maybe there is no harm in doing so?

I'm sure it would work just fine, I plan to use dry ice during transport of my must this year, it's just CO2......

If you don't have a cool / cold room to keep your must in, there are other ways to keep it cool. Set your fermenter in a water bath and keep ice in the bath, or adding frozen gallon jugs of water directly into the must, are a couple that are easy enough for a home winemaker