Using Glad wrap instead of a lid
by manticle on 09-02-2010 at 12:12 pm

Once again a common question and no article seems to exist. Please delete if my searching is inadequate, please edit if required and if you can be clear.

For various reasons, many brewers replace their lids with plastic food wrap.

WHY?

One reason might be so they can forget about whether an airlock bubbles. The main reason though is probably because you don't need to clean anything beyond your fermenter and tap.
Another bonus is that you can see directly what is occurring in your beer including the wonderful, thick, creamy krausen developing. A further reason is that you might have more success brewing two beers at once in a confined space (like a fermenting fridge) without the airlock.

HOW?

1. Get some glad wrap or other plastic wrap used for food. Stretch some out to cover the fermenter opening.

2. Take out the rubber ring from your fermenter lid. Do not throw the lid away (can be useful for when you run out of glad wrap).

3. Place o-ring over glad wrap like a large rubber band (which it is)

DO I NEED TO SANITISE THE GLAD WRAP?

In my experience no. If you have a handy spray bottle of no rinse sanitiser and it will put your mind at ease, then by all means spray away.

HOW WILL THE GAS ESCAPE?

Again in my experience, the carbon dioxide will find a way. Glad wrap held in place with a rubber o-ring is not a quarantine zone and the carbon dioxide will find its way out. The glad and CO2 production combined with healthy yeast will be sufficient in most case to keep out hostile micro-organisms. Again in my experience, it will be as effective as a lid and airlock as a barrier layer.

Some people do prick holes in their plastic wrap. To my mind this is unnecessary and defeats the purpose. Make up your own mind but many people don't bother and I've never heard of one person who doesn't who got convinced to change after a few brews.

CAN I USE PALLET WRAP?

I have heard of people who do. The stuff I've used in workplaces has a funny smell so I personally wouldn't but having never tried it, I can't say for certain that it's no good. As with all things brewing - work out what makes sense to you and give it a go. I doubt it will kill you but I'm not your doctor or your mum.

WHAT IF THE KRAUSEN BILLOWS OUT THE SIDES AND MAKES A MESS?

During this point of fermentation, the yeast is in healthy numbers and is producing carbon dioxide and alcohol. This is not a welcoming environment for other organisms but any spilt beer left for a few days on the side of the fermenter might be. Fruit flies (which can cause alcohol to turn to vinegar via acetobacter) also love this. If you fill the fermenter too full or have a super, healthy ferment with a monster yeast and krausen bubbles over the sides, simply wipe up the mess with a clean cloth, spray no rinse sanitiser on the clean areas and replace the glad wrap.