It fizzles

[Copper_clad]

I have a product I have been working on for about a year. I cooked up a large batch 5 gallons, biggest I've ever made. On this particular batch I've noticed that every container I have fizzes. Could there have been some left over sugar in the bottom and now it has primed it like a sparkling wine?

[cranky]

What exactly did you make?

[fizzix]

And what's your gravity?
I've hit 1.000 and still had fizzing a day or two later.
On some beer sites they call that "gassing." Just residual, trapped CO2 still finding its way out even though fermentation is complete.