Picking the right size fermenter

[sixdoubleo]

This weekend I'll be picking up my first batch of grapes (Zinfandel), and wanted to know if there were any basic guidelines for sizing the primary fermenter. I'll be picking them up de-stemmed and lightly crushed.

I'm getting 300lbs of grapes. Based on the general numbers I see online (12-16lbs of grapes per gallon of finished wine) that will be roughly 20-22 gallons of *finished* wine after pressing.

However, how what size container will I need for the grapes themselves during fermentation? I was going to go with the Brute food-grade garbage can and was thinking of either a 32 gallon or two 20 gallons.

Based on openwheel's Cab Sav post about 860lbs yielding 88 gallons of must (so roughly 10lbs of grapes yielding 1 gallon must) that puts my 300lbs at about 30 gallons of must.. This sound about right?

 

[Wade E]

It really depends on how much you are willing to press, the harder you press the more tannins youll extract and some of this can get very astringent from the seeds. With bigger quantities you wont notice as much but always take a cup of free run juice at the very beginning and towards the end start comparing whtas coming out as your pressing to the free run juice so youll have an idea of when to stop, a little aint bad but too much and youll taint the whole batch with this taste that can only be ridded basically by blending up with more must. I think youll be fine with the 32 but if your worried get the 2 20's. Actually thats probably a good idea and keep the free run stuff in one and mark it and then the rest in the second in case you decide down the line that you pressed too much.

 

[sixdoubleo]

It really depends on how much you are willing to press, the harder you press the more tannins youll extract and some of this can get very astringent from the seeds. With bigger quantities you wont notice as much but always take a cup of free run juice at the very beginning and towards the end start comparing whtas coming out as your pressing to the free run juice so youll have an idea of when to stop, a little aint bad but too much and youll taint the whole batch with this taste that can only be ridded basically by blending up with more must. I think youll be fine with the 32 but if your worried get the 2 20's. Actually thats probably a good idea and keep the free run stuff in one and mark it and then the rest in the second in case you decide down the line that you pressed too much.

Thanks Wade. I was sort of thinking along the same lines in terms of having two 20's just in case I wanted to try different yeasts or whatever.

By my estimations, each 20 gallon container will have about 5-8 gallons of head space. Do you see any problems with that during fermentation?

 

[Wade E]

Not at all, youll have plenty of room that way.

 

[sixdoubleo]

Not at all, youll have plenty of room that way.

Just so I understand...does it even really matter how much or little headspace you have during fermentation? I guess I was under the impression that you needed something to keep the layer of CO2 in place.

Theoretically, could I ferment 5 gallons of must in a 50 gallon container and still be OK?

 

[Wade E]

During primary fermentation you want lots of headspace for one so it doesnt overflow and two to get lots of 02 to your yeast to keep the happy. Once you get down to about 1.000 then its time to press and get it under airlock and topped up properly.

 

[sixdoubleo]

Just wanted to provide an update on this. I went ahead and purchased two 20-gallon Brute garbarge cans and they held about 125lbs each at about 2/3-capacity. I probably could have squeezed 150lbs into each but it wouln't have left much room for the cap.

So now I know for next time that I can plan for about 125lbs of must per container.

After pressing, this 250lbs yielded about 17-18 gallons of wine, which works out to just about 14lbs per gallon...right in the 12-16lbs per gallon number others have been reporting.

 

[grapeman]

I just read this for the first time. I was going to comment that 300 pounds would push the 32 gallon Brute too full. They hold 225-250 pounds each up to the ring which is a good level to allow for the cap to rise. I have 16 of them fermenting now- down from a max of 20. I rotate through them for a month to get the wine done.

 

[Wade E]

Looks perfect! I borrowed a white fermenting bucket from a fiend this year instead of buying but will get the brute as it was a little to small and I came home one day to a cap that was about 4" above the container. Luckily I never got any fruit flies here this year at all even with the open fermenter like this and this is tall enough that the cat isnt going there which surprises me cause its nice and warm!