Claire,
Unless you have an extra $100 just waiting to be spent, keep cooking with
your old jiggle-top pressure cooker. The new designs have pressure
regulators (you can set whatever pressure you want, although I can't imagine
why you'd want anything less than maximum) rather than safety valves (that's
what the jiggle top is), and better lockout devices so that you absolutely
cannot open the lid until the pressure inside is down to ambient. It's not a
good idea to be impatient with opening a pressure cooker.
The only reasons to buy a new pressure cooker are if your old one is made of
aluminum, now that we know what it might do to our brains, or if it's been
damaged in some way (overheated, overpressurized, opened when under
pressure). Otherwise, just replace the silicon gasket in the lid and keep
using it for all the recipes that take forever on the stovetop. If the books
you're referring to are by Lorna Sass, she does mention that old-style
pressure cookers need a bit more water.
I've never heard of the Manttra brand, but rather than taking the
manufacturer's word for it, some safety aspects are easy enough to verify on
your own.
1. What's the material? Only 18-10 stainless steel is acceptable; 18-8 is no
good, and aluminum is out of the question. Nobody as far as I know has been
stupid enough to try and make one out of cast iron, but if you see any,
avoid them. Don't be tempted to buy T-Fal's teflon-coated aluminum cooker;
the teflon won't last the first year.
2. What pressure is it rated for? Maximum should be at least 15 psi above
ambient; some go to 30.
3. How is the steam vented? The flow of steam must be away from the handle;
otherwise you won't be able to take the cooker off the heat in case of
overpressure.
4. Does the cooker give you any indication whether or not there is residual
pressure inside it? In other words, how do you know when it's safe to open it?
It's easy to get excited about a nifty new purchase like that, but unless
you have good reason to replace old pressure cooker, keep on using it and
spend the $100 on something more useful.
Alla Linetsky
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