A question from Carol:
Found a couple packages of extra firm tofu in the back of the fridge. Figured it would be fine – if a tad too much moisture – but thinking if I crumble it up and add maybe a third or quarter of the block at a time it’d be OK. Anyone tried tofu? Seems the meatless protein would be dandy.
This is an interesting idea – but I would definitely have some cautions as well. Firstly, yes I would agree that a meatless protein would usually be better than adding meat to your worm bin (especially in the case of meats containing lots of salt etc). Meat often has more fat than meatless protein sources, so they can get really putrid during the breakdown process. In outdoor systems this can attract flies (producing maggots) and other unwanted critters.
That said, it is important to note that any protein source is going to be very rich in nitrogen, and it is very important not to end up with two much nitrogen-rich material in the system at once. Once the C:N ratio hits a certain threshold (usually around 20:1 or below), there is more nitrogen than the microbes can take up, and the excess is released as ammonia gas – very toxic for worms.
In my experience you need to be even more careful with proteins that are combined with starchy elements – eg. legumes. Any sort of concentration of these types of materials can turn into a nasty, anaerobic goo with even more potential for problems than regular starchy materials (like breads, pastas etc).
I think something like tofu could make for a great protein source if chopped up well and mixed with other food materials and bedding – and just generally, when added in moderation.
Hope this helps!