Fermenting in a 5-10 litre water bottle?

[badgerdan]

I have a 30ltr fermenter but now I'm about to start in extract brewing I was thinking about fermenting small amounts at a time so I can try out different recipes and have 2 going at the same time but with slight differences to the recipe so I can learn what each ingrediant adds to the final taste.
This way I learn and can try different recipes at one time instead of brewing 23ltrs of just one type. Kit wise this is fine but I want to leave fermenting large amounts until I have a recipe I like and want lots of

Can I just use 5 or 10 ltr water containers for this, with an airlock on the top of course?

[Invalid Stout]

Of course you can. You just need to make sure that the container is big enough to cope with the yeast head. And very small batches, less than four litres aren't worth doing as the proportion of trub and sludge gets too high, to say nothing of the work involved.

[badgerdan]

Ok, how about a 10ltr tub with 8ltr of beer in, would that work?

[boingy]

Yep, as long as the tub is food-grade that would be fine. A couple of litres headroom is more than enough for the yeast to stay in the tub rather than overflowing!

[badgerdan]

Excellent. I think my local supermarket has some 10ltr ones but how do i know if they're food grade? The ones i've seen are made for people to take drinking water for when they go to stay in their log cabins in the winter holidays.

[Invalid Stout]

If they can legally sell drinking water in them, then they're food grade.