POTATO
Potatoes have an interesting history. Brought to Europe by the Spanish, they quickly became a popular food because of their resistance to coldness and therefore a relatively easy cultivation. They were also, and still are, one of the cheapest vegetables around. Everyone, from the poor to the rich, had a new vegetable in abundance. Nowadays, potato is the main vegetable produced in the world.
Potato is a tuber, which means that it develops from the stolon from underground. The characteristic eyes on a potato are the basis for growth of stems and roots of a new plant, as you might have witnessed on some old potatoes. The flavor of a potato is simple and consists of a combination of three basic flavors - sweet, bitter, and earthy. The sweetness comes from the sugars in the potato, bitterness comes from solanine and chocanine, and the earthy flavor is generated by the microbes that live in the soil wherein the potato grows. Some earthiness is also created within the potato itself. The nutritional value of potatoes is high - they contain lots of starch and vitamin C, as well as fibers.
The content of starch within the potato depends on their age. New potatoes, harvested during late spring and summer, contain little amount of starch and high amount of water. The situtation is reverted in the old potatoes. Storage of potatoes is normally done in low temperatures, around 8 C/45 F, during which they can develop even more flavor. The main difference between an old and a new potato is then the starch content and the amount of flowery taste in it. The old potatoes also contain some simple sugars, because some of their starch becomes digested by their own enzymes when kept in old environment.
Cooking with potatoes is simple, altough it is quite important to match the kind of potato you use to the dish you want to make. Basically, we can say that there are mealy (high starch, old potatoes) and waxy (low starch, newer potatoes) potatoes. They each have a different texture, due to their different starch to water ratio. When you cook a mealy potato, you want to use it for mashing or baking, as well as for frying. The heat will cause separation of the clustered starch-packed cells and create a fluffy texture. On the other hand, waxy potatoes with their low content of starch, do not experience that much starch swelling action, so the cells inside them don't separate but rather converge due to heat. That's why the new potatoes are so dense and the old potatoes are so fluffy. Waxy potatoes are used in salads, gratins, or dishes where you desire a denser texture.
When potatoes are cooked, their basic flavors should be noticable, and the texture should be fairly soft but not too soft. They should be easy to bite through, all the way into the core of potato. If the potato tastes very bitter, don't eat it - it has too many solanine and chaconine toxins, and they can be outright dangerous for your life. If the potato becomes discolored after cooking (gets grayish after some time of storage) it is due to oxidation, and this can prevented by coating them in some acidic liquid, e.g. lemon juice or vinegar. On our HOW TO pages, you'll find more about all basic techniques of cooking potatoes.