I’ve come across several recipes (specifically for lefse) that require old or mealy potatoes. I assume some desirable chemical conversion occurs over time. My question is, how old is old? Months? Years? Is there some lower limit that makes a potato “old”?
Also, how do you determine if a potato is “mealy” with just a cursory examination in the supermarket?
Are you sure they’re asking for old potatoes?
Do the recipes call for “old potatoes” or “mealy potatoes?”
“Mealy” is a term for the texture of some potato varieties, as compared to “waxy” potatoes.
Mealy are better for mashing because they don’t get sticky & gummy when you mash them (unless you’re a very enthusiastic masher).
Russets are one mealy variety.
Waxy are good for potato salad because they hold their shape well after they’re cooked.
There’s also something called all-purpose potatoes, e.g. Yukon Gold, which are sort of good for most purposes but not perfect for any porpose (if that makes sense).
Some further reading:
Solanine is a toxin present in potatoes, which are a member of the nightshade family. Solanine may be present where potatoes have sprouted, so I would expect it to be more prevalent in older potatoes. It’s not going to kill you, but it may give you a tummy ache. If you’re going to eat old potatoes, I’d recommend cutting off any green bits, or “eyes” where the potatoe has sprouted.
Some links:
http://www.straightdope.com/classics/a2_055b.html
http://www.drweil.com/u/QA/QA252785/
I think they mean not new potatoes.
Potatoes come in two broad types; floury and waxy; the waxy sort are mostly first and second ‘earlies’ - typically planted just after the last frost and harvested in full growth, yielding a moderate crop of smallish, firm potatoes, often elongated in shape, with thin, sometimes flaky skins and cooking to a firm, often translucent ‘waxy’ consistency.
The ‘floury’ sort are mostly ‘maincrop’ varieties that are sometimes planted a little later and are harvested as the top growth dies off - typically yielding a larger crop of large, usually fat and round in shape, potatoes with thicker skins, cooking to a fluffy, mealy texture.
As a rule of thumb (to which there are exceptions) in the supermarket, roundish, pale-coloured potatoes will be floury; smaller, blimp-shaped yellowish ones will be waxy.
If the pack says they are ideal for mashing or roasting, they will be a floury variety; if it says they are good for potato salad, they will be waxy.
Here’s some examples of recepies that require “old” or mealy potatoes:
http://www.amazon.com/exec/obidos/tg/guides/guide-display/-/1K90HUXSYIQ0I/104-4604187-3179167
http://www.bbc.co.uk/h2g2/guide/A533422
http://www.recipecottage.com/breads-pancakes/lefse04.html
http://www.cybershingle.com/recipes/pages/lefse/lefse1.htm
http://www.creativekitchenonline.com/story/lefse/