Here's a good, short description of the manufacturing process with a link to the full site following:
"Basic regular tofu is a white, essentially bland, soft product, closely resembling pressed white milk curd. Its production starts with the preparation of soymilk, as described in the previous chapter. Soybean is boiled, then cooled to around 75o C. The thin protein-lipid film (surface scum) formed on the surface of the milk is removed. A coagulant, which consists of a slurry of gypsum powder or a solution of magnesium salts (nigari) is added. Curdling occurs. The free supernatant whey is removed and the curd is transferred to perforated boxes and pressed until a coherent block of curd is obtained. The curd is next immersed in cold running water for several hours, with the purpose of cooling and leaching out excess coagulant and entrapped whey solids. The block is cut to retail-size portions and wrapped for marketing. Fresh tofu is stored, transported and sold as a refrigerated perishable. The analogy between tofu production and cheese manufacture is evident."
"off" tofu stinks really bad, but mine always lasts ages past the sell by date on the package and keeps a few days in fresh water in the fridge.
I rinse it under a running tap before I eat it.
“There is a distinct difference between having an open mind and having a hole in your head from which your brain leaks out."-James Randi
Random story: when my in-laws were visiting us, my MIL somehow decided that since I like tofu so much, I should just eat it straight from the pack with nothing on it (no one would dare do that for chicken or pork but yet for tofu... ). Anyway, I was acting like I wouldn't do it (only for effect, though), and 'finally' I said "okay... you wanna see me eat tofu out of the box, here it is." and I took a slice and ate it! She started to gross out and then she started yelling for my FIL to "Come in here and see what Dee's doing" when he came into the room, she nudged me and said "do it again" so I sliced another slice off and ate it. My FIL said "I can't watch that" and left the room right away and left my MIL's standing there, saying over and over "I CAN'T believe you ate that... I can't BELIEVE you ate that."
Ahhh... fun with the inlaws. There's nothing like it.
I don't like it plain raw.But I do like it when it is blended into smoothies,desserts or tofu ricotta.I have never had a problem.My friend eats it plain raw with a little soy sauce and I've never heard him complain about any illness from it.