Fuel Stabilizer Recommendations?

[PaulSmith]

I took this picture of a carb bowl from a zzr400 I was servicing for a lady friend. This bike was fuelled up just before xmas a couple of years ago and left in a dry garage until beginning of March when it was started up and then decided to misfire on all cylinders and generally run like crap.
This is what you risk getting in your carbs if you leave a bike for a coupl of months without using preserver or draining the carbs. And no, it isn't caused by water ingress in the tank/carbs, it's fuel gone 'off'

That is a stunning mount of gunge in the carbs. How much of it was already there before the bike was parked up for the winter?