How to Pick and Store Mushrooms - as part of the expert series by GeoBeats. Nowdays, the choice of mushrooms is really enormous. Some supermarkets might have upwards of eight or nine different kinds of mushrooms. So how do you buy them, how do you store them, how do you prepare them and keep them? Well, one of the things that you should remember, and I am just going to talk now about the most common mushroom, which is actually called the "common mushroom" or the "white mushroom" or the "button mushroom", that is the most common mushroom you will see everyday. You can buy them loose, which is how I prefer to buy them because I can buy the amount that I want, and I can examine each one, as opposed to a basket of mushrooms, where I cannot examine the mushrooms. Mushrooms look dirty. that really is not dirt, that is some of the particle of the mushroom that has rubbed off. When you wash a mushroom, do not. You do not wash mushrooms. You brush them with a mushroom brush, or I use a paper towel that has been rolled up and I just brush some of these little particles away, and that is all you need to do when you use your mushrooms. But let's say you cannot use a mushroom right away. How do you store it? Well the first thing you do not want to do is you do not want to put it in a plastic bag, you do not want to put it into a refrigerator, and you do not want to cover them. Because if you do, they will become wet, slimy, and they will deteriorate very quickly. The best way to preserve a mushroom is leave them out, or put them in a paper bag. What happens if you are not using them right away is that the mushrooms will become drier and drier, and that presents no problem at all because a dry mushroom can always be rehydrated with water, whereas a slimy mushroom is just a slimy mushroom that never dries out. So keep your mushrooms out. Do not worry about them drying out. The moisture will come later when you cook with them because you are going to be cooking them in some kind of cooking fat, or some kind of water, or some kind of sauce, and they will be rehydrated naturally.