High protein foods tend to be disastrous in an earthworm bin. They decompose very quickly and release ammonia, which is toxic to earthworms, and other bad-smelling substances. They attract flies and other nasty creatures. They lead to earthworms getting deformed and dying (string of pearls).

To feed Tofu safely, you should dry it in a microwave oven and blend it into a fine powder. Dust a small quantity of the powder very lightly over the surface of your bin and cover it with paper. If it's gone after 24 hours, repeat the process until its all gone. Some people have safely disposed off powdered milk this way.

I think protein poisoning is actually ammonia poisoning. Decomposing protein releases ammonia, which earthworms are very sensitive to. In the presence of carbohydrates, ammonia released by the breakdown of protein is quickly taken up by microbes feasting on the carbs. With high protein foods, ammonia utilizing microbes can't absorb all the ammonia, so it accumulates until it reaches levels that can injure and kill earthworms. High protein wastes in nature - for example, animal carcasses - are usually eaten by maggots, which have a high tolerance for ammonia.

I think the advantage of grinding your tofu into a fine powder and sprinkling a little bit of it around your bin is because it will maximize the area of contact between your tofu and the ammonia utilizing microbes in your worm bin. An even better way is to lay some moist paper over the bin contents and sprinkle your tofu powder over it.

I think you're correct that ammonia is the harmful agent there. Which is why I think making sure there aren't big solid blocks of high-protein matter and that the area where it's found is small enough to be avoided by worms until it gets to a condition they like is important. I guess I don't see much added benefit in going through all the trouble of processing it so very finely, though.

Maggots are most visible on animal carcasses because they produce and excrete enzymes that actively digest dead tissues and therefore can feed very quickly and efficiently on carcasses and colonize them rapidly. Worms can't do that and have to wait for microorganisms and critters like maggots to break the carcass down more.

There are certain nitrifying bacteria in the soil that will turn ammonia into nitrite and then another group of nitrifying bacteria will convert that nitrite to nitrate which is harmless to the worms and really good stuff for plants. This happens to be is the nitrogen cycle in fish ponds and aquariums as well in which ammonia (and to a lesser extent nitrite) is harmful to the fish because it is in solution... however in a worm bin with the lid off, whatever ammonia that doesn't gas off will be confined to the area where you put the source and so is easily avoided by the worms.

Personally, if it were me I'd just dump the tofu in one corner of the bin and not worry about it... the nitrifying bacteria will multiple rather quickly and make short work of it unless the worms decide they what a piece of that action too. I know my worms grow and multiply on the prodigious amounts of powdered grains I feed them on a regular basis... protein is good for them... heck if you think about it they are mostly made up of water and protein anyway. Ammonia is just a degradation by-product produced by certain nitrifying bacteria in the soil, the worms will not get near if they find the concentration irritating... same thing with carbohydrates, yeast can take simple sugars and convert to alcohols, and certain bacteria create phenols, etc. These are all by-products of the creatures that inhabit a compost pile, which is all a worm bin really is. If the concentrations get too high the worms have mobility and will just move/keep away until its their turn.

Compost piles are ecosystems... Ever since my bins balanced out, I have no fear and feed whatever organic trash we have available... I just break it down small enough that the worm bin inhabitants can reduce it quickly... I think the worms are being given too much credit, the heavy work is done by bacteria, yeast, fungi. Okay, so I refuse to feed them citrus rinds and give only very limited amounts of meat and fats mostly because I don't want to attract big hairy pests and flies and also rotting meat stinks.

OK, I have read enough - the tofu is NOT going into the worm bin! Instead, I'll break it up & mix it into the outdoor pile. Thanks for the interesting & enlightening discussion, everyone.

I would do it. If I ever get a reason to throw some tofu in the bin, I'll report back.