Wine Fermentation issue

gazzor114 · Mar 4, 2012

I am new to homebrew and would be grateful for some advice, I purchased two 22.5L carboys which came with caps. These caps are designed to fit both an air lock and thermometer and just push over the top of the carboy glass lip. Started my fruit tea wine must on the Friday and the fermentation started bubbling on the Saturday, this carried on until the Wednesday when it appeared to stop.
I noticed that bubbles were still being produced in the must, so I contacted the shop I bought the equipment from on the Friday, I had been hoping that it would restart again but to no avail. The shop suggested putting petroleum jelly on the cap to create a better seal, this was done on the Saturday and the air lock immediately started bubbling.
My question is that if the yeast will only produce alcohol in a non oxygen environment, could I have affected the % of alcohol, taste or any other factors

pittsy · Mar 4, 2012

no worries , yeast will do there thing in an open container but you dont want to do that as germs and wild yeasts in the air floating around would cause an infection , do you have a hydrometer , if yes then after around 1 to 2 weeks take a reading and when you have no movement for 2 to 3 days running its done (as long as its around the expected final garavity reading) did you take a starting gravity reading (also called an original reading ) if yes then you can work out with a FG reading the % of alcohol you have at end of fermentation, good luck and welcome to the greatest hobby :clap:

RobWalker · Mar 4, 2012

Aah this old chestnut... :-)

The only way to track fermentation is with a hydrometer. Fermentation releases all sorts of gas, and even when it doesnt, its not neccessarily stopped fermenting. Your booze will also create a co2 cloud that will keep out most infections, and the oxygen is pushed through the airlock at the start by this. Oxygen would ruin the taste of your wine but you should be fine, some people ferment with the lid hanging off - you just need to get it racked quite quickly after fermentation if you have any sort of air exposure :-)

Abv will definitely not be affected, its a straight a to b from sugar to alcohol :-)

bobsbeer · Mar 4, 2012

Welcome to the forum Gazzar. Don't worry about the lack of seal. It is best to keep the air out if you can but don't get too worked up about it. The wine will do it's own thing. After about a week or 2 check your SG. The reading should be around .990-995. The nearer to .990 the dryer the wine will be, and that's about as low as it will go. All will be fine and don't worry.

gazzor114 · Mar 4, 2012

My hydrometer initial reading of the must was 1076, so after your advice I will wait till next week and re-test

Thank you for your help with this issue.