Demi-Johns & Carboys

The difference between a Demi-John and a Carboy is size. Carboys are much bigger and hold more liquid than Demi-Johns.

Demi Johns and Carboys are designed as a secondary fermentation vessel.

The initial fermentation should be completed in a larger vessel such as a brewing bucket. This is because the initial fermentation is very vigorous and gives off a lot of carbon dioxide. The carbon dioxide helps prevent infection, but this can cause a large amount of foam on top of the fermenting liquid. If the initial fermentation is performed in a demi-john or a carboy, you risk the airlock becoming blocked by the foam, when can then lead to the possibility of an explosive eruption and a lot of cleaning up.

Once the initial fermentation slows, less carbon dioxide is given off. This means there is more chance of infection. This is the time to syphon your fermentation into a vessel with a smaller neck with an airlock such as a demi-john or a carboy.

The Demi-John or Carboy allows you to ferment wines over a long period and helps prevent infection from airborne bacteria.

Demi-Johns and Carboys are not designed to hold a carbonated liquid, so a solid bung for long term bulk ageing should only be fitted if you are sure the fermentation has completed. For security, a safety cork or airlock should be fitted.

Let customers speak for us

from 343 reviews

Marion Charles

SG Wines (Solomon Grundy) Classic - Sweet White - 7 Day White Wine Kit - 30 Bottles

Brilliant tasty glass of wine.

We have purchased this wine kit numerous times. We have always had a good quality pack of wine. Presented chilled this wine is as good as any shop wine.
Always ready to drink within a couple of weeks .

01/21/2025

Jon Pinnock

White Wine Enhancer and Enricher - 1 Litre - Grape Juice Concentrate - Youngs Definitive

If you want to make a quality wine that you used to by

Quite simply add this .
You will have the fermenter foaming all over the floor and walls but you will have the real quality that you want .
Made fruit wines of all types for years and on some as a hobby , had a go last year base level wine kit and so so ,a bit sweet ok if you only want to get well oiled . But this added to a kit is wow for a nearly sixty year old wine drinker just try adding half the bottle to your next 30 bottle kit you will never go back.

11/14/2024

andy mainwaring

Wine Bottle Shrink Capsules (Caps) - Matt Black - 30 Pack

Bottle tops

Very good works a treat.makes the wine look professional and attractive to the coinesseur.

10/19/2024

Louise Wheeler

Large Mashing - Sparging - Straining Bag

Straining bag great item

I made my first ever wine, blackberry wine using this bag after following David on his Youtube video, great product, less mess and easy to use. Thank you David for your help and support with my order.

08/26/2024

Richard Fothergill

Mangrove Jacks - Apple Cider - 40 Pint Cider Kit

Mangrove Jacks apple cider kit

Easy kit to brew. Pleasant, very refreshing apple flavour ideal for lazy summer days in the sun. Very impressed and intend to try others in this range.👍

06/20/2024

Alex Balfour

Muntons Gold - Imperial Stout - 40 Pint Beer Kit

Early days

Eventually started this one and it went off like a rocket initially. Took a reading yesterday and it was a bit off the recommended fg but will give it another week and check it.Smells amazing though.🤞🏻

02/15/2025

Colin Archer

SG Wines (Solomon Grundy) Gold - Chardonnay - 7 Day White Wine Kit - 30 Bottle

Lovely wine

Fast delivery,arrives well packaged
Excellent value for money and easy to follow instructions 10 out of 10

02/15/2025

jase

Simply - Lager - 40 Pint Beer Kit

simply lager

perfect full of flavour when partnered with light lme pack full bodied taste this man knows his stuff happy as always

02/15/2025

Laurence H.

Spin Vinator - Bottle Washer Steriliser and Rinser for Beer + Wine Bottles

Good

I use this for sterilising bottles, using a zero rinse liquid, before siphoning home brew beer.

02/12/2025

Anthony Davies

Tom Caxton Dark Real Ale Beer Kit - 40 Pint

Tom Caxton Dark Ale

I have brewed this kit a few times and it has always produced a nice tasty ale, I would recommend it to anyone who hasn't tried it yet!

02/11/2025

Anthony Davies

Tom Caxton Dark Real Ale Beer Kit - 40 Pint

Tom Caxtons Dark Real Ale

I have brewed this kit a few times and it has always turned out to be a nice tasty ale, I would recommend it and I will certainly be brewing it again.

02/11/2025