Food for thought: Why are some potatoes good for boiling but not others?

With more than 80 varieties of potato available in the UK, selecting the right type to make the perfect mash can prove problematic. Although there are so many, all potatoes have the same composition; the outer skin (periderm), the flesh and the inner pith. Starch is the major component of the potato.

Cooked potatoes have different textures, depending on whether they are "waxy" or "floury". Waxy potatoes are translucent and may have a moist and pasty feel, and their cells are packed tightly together. This structure means the potatoes can be boiled and not become mushy. Floury potatoes are brighter and more granular in appearance, which gives them a drier feel, and their cells are loosely arranged. This structure allows them to be baked or boiled for mash.

For example, the Pentland Squire is suitable for mashing, the Pentland Dell for chipping, the Cara for boiling and the King Edward for anything except boiling. The type of potato and the conditions it is stored in are also very important factors in making chips, as they determine the levels of sugar present in your vegetable and will affect the chips' final colour. Roy Ballam, British Nutrition Foundation