well, it all depends. the taste varies from place to place, depends on where you harvest it from. the best place is always as close to a water source as possible. grass growing on the edge of a lake or stream is best.
also, there are types of grass that taste better. for instance the grass with a round, hollow body tastes best, grass with the flat blade tastes very bitter. also, the more it has rained, the better the grass tastes. if its rained for a couple days, then is bright and sunny, thats the best time to harvest.
how much carrots do you use in your wheatgrass growing medium? do you mean the carrot pulp ejected from the juicer?