Mary asked Rolando why the lemonade is bright pink instead of blue. He instantly said the name of this chemical. For those of you who don’t know Rolando, he used to be a culinary professor, so it’s not weird that he knows this. Turns out, blueberries aren’t actually blue, they’re purple, and when you mix blueberries with lemon, the reaction between that chemical (anthocyanidin?) and the acid from the lemon juice makes this bright pink color.