About 10 or 15 years back, my Primary Care Physician was going over my meals with me. I told him I created a protein drink the night before, set it in the refrigerator, and brought it with me as an "after workout" drink the next morning. He asked why I did not bring the protein powder in and mix it after my workout. I explained that the drink had smoother texture after sitting overnight in the refrigerator. He said that smoother texture is because the protein I am using is breaking down after being mixed with water, and that a portion of it has been converted to fat. Since then, I put my powder in a mixing cup and add the water when I am ready to drink it. Seeing premixed drinks sitting on the shelf makes me question this. They taste like ass, so they could have an added chemical to keep the proteins from breaking down. Or, maybe only certain proteins (like Ionized Whey) break down after being mixed. I'm not interested in Bro Science. But I would like to have someone explain to me if my doctor was mistaken or if there are certain proteins that break down faster than others - and possibly explain to me what is going on.