There are products that are directly derived from soy, soy sauce, soy protein isolate, and soy milk for example. The reason they are still identified as “soy something” is because the soy proteins, soy genetic materials and anything else that is particular to soy is still contained in them. Those proteins are the culprits in soy allergy
But when you see an ingredient labeled tocopherol, or saponin, or stannol, even though these may be derived from soy (they may be derived from many other sources as well), the fact that the ingredient is not labeled soy tocopherol, or soy saponin, or soy stannol tells you that there is no soy in it. In other words, what you have is pure tocopherol or pure saponin, or pure stannol, there is no soy in it anymore.
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