demijohn

pog it

Hi all, I need to ask a 'stupid question'!! Sorry!

I'm going to try making a wine for the first time, and I have to get a demi-john to but the mixture into- I know that a demijohn is a 1 gallon sized container, but what makes a demi-john useful for this? Has it got a special way to close or something and is therefore airtight??

Thanks a mil for any help.

BeerNut

I think it's just easier, since homebrew buckets are generally 5 gallons. Demis are better for aging things in because glass is less permeable than plastic. And, as you say, the narrow neck makes them easier to seal.

Mantel

They're fairly narrow at the top which lets you put in a stopper with a hole in it (called a bung) which lets you put in an airlock. The airlock is used to let air out but not in since you get alot of CO2 in the brewing process. The demi is clear aswell so you can see how things are going just keep it in a dark place while it's fermenting

rubadub

Being clear you can also see if it has cleared when fining. Also since it is shorter than a big tub the yeast settles to the bottom faster. Also are easier to handle etc, the lugs are nice to hold. Many also perfer the fact their drink has only been in contact with glass for long periods, a glass carboy costs a lot and weighs a lot.

oblivious

rubadub wrote: »

a glass carboy costs a lot and weighs a lot.

An there have been a few interesting visits to A&E too:p

pog it

Thanks so much, that's gonna be a brill help.

With regards the airlock though- at what stage do you take this in and out?! I had been thinking the bung was enough on its own - that it was a good sealer, but how long would you need to let the air out and how would you manage that air didn't get in?!
Sorry I'm a total novice!

rubadub

pog it wrote: »

Thanks so much, that's gonna be a brill help.

With regards the airlock though- at what stage do you take this in and out?! I had been thinking the bung was enough on its own - that it was a good sealer, but how long would you need to let the air out and how would you manage that air didn't get in?!
Sorry I'm a total novice!

Do not fully seal it! when it is brewing it basically turns the sugar into carbon dioxide gas, yeast and alcohol. More oxygen in the brew will lead to more yeast being formed. This can be important at the start to get the brew going with a good amount of yeast. Many brewers who boil their unfermented brew will aerate it since boiling will drive off the oxygen.

Once the brew is going you do not want more yeast made (at the expense of alcohol), so you put a airlock on, this allows excess CO2 to escape by bubbling out, it will form a head of CO2 over the top of the brew. It also keeps bugs out which might be attracted to the smell of brewing wine, also keeps dust out.

If fully sealed the gas has nowhere to escape and it could even explode if you jammed the bung in really tight.

An airlock is not essential, I used to just jam in some kitchen roll or cotton wool, this allowed gas exchange while keeping nasties & dust out. CO2 is heavier than air so it forms a layer over the brew so in that way oxygen is kept out.

The bubbling airlock also lets you know if the fermentation is taking place, if speeding up or slowing down. When it stops bubbling you can take it out and check with a hydrometer. Again a hydrometer is not absolutely essential, I used to often just taste a spoonful to see if it was dry (not sweet) so you know all the sugars are probably fermented out.

pog it

wow

Thank you! one last little question- is brewing basically the same as fermenting? As in you make the brew (the mixture) and it goes to fermenting stage (brewing)?

Mantel

pog it wrote: »

Thanks so much, that's gonna be a brill help.

With regards the airlock though- at what stage do you take this in and out?! I had been thinking the bung was enough on its own - that it was a good sealer, but how long would you need to let the air out and how would you manage that air didn't get in?!
Sorry I'm a total novice!

The airlock is in an side ways s shape, you pour water in to one side so it's about one third filled on both chambers. This makes an airlock that will let the CO2 build up out without the top going pop due to a build up in pressure and will let your yeast ferment in peace without any nasty things getting in to ruin it.

http://www.youtube.com/watch?v=CBHVKp6ePQg [Airlock in action]

Mantel

pog it wrote: »

wow

Thank you! one last little question- is brewing basically the same as fermenting? As in you make the brew (the mixture) and it goes to fermenting stage (brewing)?

Yes, fermentation is turning sugars in to alcohol using yeast. Once you have everything in the container of choice and you add the yeast, fermentation will kick off shortly afterwards, anything from an hour to a day or two once the yeasties go to work

BeerNut

pog it wrote: »

is brewing basically the same as fermenting? As in you make the brew (the mixture) and it goes to fermenting stage (brewing)?

Not exactly. Strictly speaking, brewing is just dissolving stuff in boiling water. Fermenting is what happens afterwards when the mixture is cooled and the yeast goes in. But the term "brewing" is often used for the whole process from mixing the ingredients through to bottling/kegging.

You'll often hear people talking about "brewing cider" even though no actual brewing is involved.