is partly a psychological exercise. You like to have a mouth that feels minty fresh. But there is no reason why toothpaste has to taste like wintergreen or peppermint or whatever you use. We could easily make toothpaste that tastes like barbeque sauce, or dark chocolate, or blood. Partly you're brushing your teeth to dislodge microscopic food particles and hit your oral bacteria with something nasty. But partly you're brushing because you want your mouth to taste like mint.
So now that you know that the minty taste is not necessarily coupled to the plaque-fighting ingredients, don't you wonder if the toothpaste makers ever skip on the important stuff, safe in the knowledge that you won't perceive a difference (at least for a while)?
Incidentally, I think the best way to avoid the horrible face that you get when you try to drink orange juice too soon after brushing is to just make orange-juice-flavored toothpaste. That way you're ready for anything! Another seemingly unsolveable problem solved. I'm going to sign off and bask in the warm glow of my own genius for a while. Cheerio!