Got a question the other day about gelatin that I’ve been meaning to get to. That is: why are gelatin desserts on the no-no list for vegetarians? The reason is that gelatin powder is an animal-based product. It’s made by boiling cattle and/or pork skin and bones for extended periods of time, then reducing and drying the liquid. Contrary to popular folklore, it doesn’t come from hooves.
Gelatin, as I mentioned before, is a type of protein. Ropes of gelatin molecules known as collagen make up a significant portion of the so-called “connective tissue” in animals. These are things like tendons and ligaments, the cables and belts of the body, that transfer and apply the work that’s done by muscles. Pretty tough things, they are. Even after extended boiling, they don’t really break down all that much. Yet some gelatin molecules are knocked free by the heat and disperse into the water. You can see this process in action when you make meat stocks. Since collagen is also found in high concentration in bones (especially veal bones) long-simmered stock becomes thick and jelly-like when you cool it. Beef consommé is an example, something my grandfather used to love to drink over ice.
Jellied meat stocks have been used to make savory foods like aspics since the Middle Ages. However it took until the Industrial Revolution for gelatin to be isolated as a dry powder, which made it useful for sweets.