has anyone heard of fruit pectin?

monday my boyfriend is going to take a piss test so he can start working at this local business..

my mom gets piss tested monthly because she is on parole.. she also smokes weed daily.. she passes each time by using fruit pectin (which she says can be bought in a grocery store)

you mix it with half a gallon of water, drink it all (without throwing up.. supposedly it tastes horrid).. then piss at least three times before you go.. do all of this 3-5 hours before the piss test.

she says its supposed to work. hopefully it will. has anyone else ever heard of this method or used it?