Yes it can be used as long as you didn't burn any coal or coke with it.

Thanks for the info, i was worried about the possible ash taste in any of the veggies.

No taste of ash just sprinkle over the surface before you sow.

Ash is high in potassium so is good for flowers and fruit rather than green growth. Don't put it on your raspberries as the pH is wrong for them. It is very soluble so keep it dry until you want to use it - no use adding it in autumn for a spring sowing as it will wash out over the winter.