I decided to do my first ever wort stability test on this last brew. As I understand it 3 days is a passing grade. Mine went five!
I’m wondering what your longest is.
What is a wort stability test?
A wort stability test is a way to test your brewery sanitation practices. Take some boiled and cooled wort, put it in a covered sanitized container (I use a glass horseradish jar) then set it somewhere warm. It should go three days without going sour, making CO2, developing bacteria and mold, etc. If not you probably have something contaminating your wort (dirty chiller, tubing). See the following from Wyeast:
Hmm. I’ll need to try this on my next batch. Pour off a pint or so into a sanitized mason jar and see what happens.
I’m brewing Sunday morning. Think I’ll give it a try.
I do it periodically to check my sanitation practices pre-ferment. I usually am able to go seven days with no visible activity and no drop in gravity.
I’ve not done this before, but it’s on the list for my next batch. I don’t typically have contamination isues that I notice…but maybe they’re small problems that I’m just not picking up on. I think this test is a great idea and it really doesn’t cost much. I imagine just a cup of wort in a Ball jar would be plenty, right?
Yep
Enough to fill a hydrometer tube I bet. Probably less needed if you have a refractometer.