Great question! I have heard many mixed reviews on whether or not the store bought sour cabbage has the same probiotic potential, but have never read any scientific studies on such. As such, I prefer to make my own. There are certain brands I've bought in a pinch that I've found certainly do have a high probiotic count (you can normally tell by opening the bottle and the pressure created from fermentation causes juices to spray everywhere), but it is the safest bet to make your own. :)