ࡱ > y { x '` R bjbjVwVw F 4 4 e q R R R R R R R f 8 f 7 . : : P P P $ e h ͆ d ā - R h h @ ā R R P P F F F R P R P F F F ~ l 8 R R t P . p}e"& o X 0 7 p l 1 ^ 1 t t 1 R J} T F ā ā X 7 f f f * f f f * f f f R R R R R R Cooking Under Pressure When you boil potatoes on the stove top, it can take half an hour to cook them til tender. But, when you boil them in a pressure cooker, instead presto, theyre ready in about five minutes. Whats the difference? What makes pressure cookers cook so quickly? Lets start with the potatoes boiling on the stove top. The temperature of the boiling water wont go above 212 degrees Fahrenheit, no matter how high you turn up the burner or how long you leave the pot on the stove. Thats because, at normal air pressure, water boils at 212 degrees and escapes as steam. In a pressure cooker, on the other hand, the steam cant make such an easy getaway. The sealed lid keeps the steam inside, raising the pressure inside the cooker to about twice normal air pressure. Now heres the secret of speedy pressure cooking. As pressure rises, so does the boiling point of water. At the higher pressure inside the cooker, the boiling point of water goes up to about 252 degrees. So, food cooks at a much higher temperature in a pressure cooker, and that`s why it cooks more quickly. Pressure cookers control cooking temperature by maintaining a certain pressure. A vent on the lid releases steam when the right pressure, and therefore the right cooking temperature is reached. And to prevent disasters like boiled potatoes exploding onto the ceiling, modern pressure cookers also have a safety valve to release steam, just in case the vent gets stuck. 0 0ؚSpj 0 0Yg\WF>e(WpP[ Npnq JS\eMbnqq0Yg\WF>eeQؚSS ww5 R1\qN0$N gUO:S+RbT? :NUOؚSpjYdkŏ? 0 0bNNpP[ NnqvWF _Ywe`O\dqlvpY'Ybb/fpjeY4lvlp NOǏNSl2 1 2 ^0ُ/f1uN(WhQ'YlSN4l0RNSl2 1 2 ^1\Ol~v^b_b4ll%cSc0 0 0[NؚS 4llv^ NOYdk[f%cSQS0[\v\4ll\X[(W̑QS:_GShQ'YlSv$N P0 V Z \ h j ҽһҲzofa[Q[Q j hCi KH U hCi KH hCi o(hCi 5PJ o( hCi 5CJ PJ o( hCi 5CJ OJ PJ o( hCi CJ OJ PJ o(hCi j hCi UmH nH sH tH h?q j h?q Uh4 h[3 aJ U)hoch hoch B*KH OJ QJ ^J aJ ph -hoch hoch B*CJ KH OJ QJ ^J aJ ph +hoch hoch 5B*KH OJ QJ \^J ph M G N gd4 $ dw d d 1$[$\$a$ gdoch $dw d d 1$[$\$a$gdoch ~ 0 0s(WbN _ؚS_pjvy0@wQS:_ NGS4lvlp_NnGSؚ0QS~c(Wؚ4ls^4lvlp NGSNSl2 5 2 ^]S0Vdk(WؚS-Npjߘirv)n^fؚpjef>f)w0 0 0ؚSǏ~cg NSRegpj)n^0[\v NvclT[ʑ>e4llNdk0RTvSRpj)n^_NKN0Rt`