Making Liquid Fertilizer?

3 weeks ago I hit on the idea to make my own fertilizer for tomatoes, cucumbers, etc. I used a plastic bin, put a tap in it about 6 inches up from bottom and put all raw bits of carots, potatoes, nothing cooked, all raw, anything that we normally sling in the refuse bin. I looked at it today and it's got white froth on top. Can I really use this stuff? I am now tempted to sling it as it smells very high. I have added some Dobbies plant food liquid fertilizer for good measure, too.

By Stan