PQQ is another "maybe" vitamin. It participates oxidation and reduction and is found in trace amounts in whiskey (it leaches from the charred oak) and other fo

PQQ is another "maybe" vitamin. It participates oxidation and reduction and is found in trace amounts in whiskey (it leaches from the charred oak) and other foods, and often formulated together with coQ10. PQQ was almost declared a vitamin a decade or two ago. If you have the pure crystals, drop just a tiny one into a glass of water and watch it dissolve as it sinks. Beautiful show! Also, you'll see it changes color with pH.