|The spring-valve of the Duromatic pressure cooker by Kuhn Rikon allows the user to determine the exact time at which the interior of the pan comes to pressure and thereby affords much greater accuracy in the timing of cooking.
When the first red ring appears, the internal pressure has been raised 8 pounds per square inch (psi) above the external pressure. When the second red ring appears, internal pressure has been raised 15 psi above the external pressure. The Quick Cuisine cookbook (included with every cooker) tells exactly how to use the ring indicator for each recipe, and provides guidelines and tables for using the same techniques for any food you may wish to prepare.
The weight valve system on older pressure cookers and on some contemporary pressure cookers gives no clear indication of when full pressure is achieved; the user must guess as to when this has occurred. Kuhn Rikon's spring valve system, by providing more accurate timing, allows superior cooking results.
A weight valve system allows a great deal of steam to escape. When a large amount of steam is escaping, there is a constant hissing noise, an increased likelihood of a clogged valve, and greater evaporation of moisture. Duromatic's valve allows cooking with less water (thereby retaining more of the vitamins, minerals and natural taste of the food), almost eliminates clogged valves, and is much quieter than cooking with a weight-valve system.