Yeah keep it cold!!!
DONT leave it in your bag....within a couple of days it ll fur up like some sort of new life form [xx(][xx(]
It seems to go off very quickly, probably the bread element in the groundbait.
I dont even mix mine up before the day anymore, just mix enough up on the bank to last a couple of hours and mix more up if needed. Mainly due to during hot weather, it goes a bit cakey, and a skin forms on the top, so keep it covered.[

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