Pressure Cooking a way of cooking things at a higher temperature than is normally possible, by increasing the air pressure in the recipient and thus raising the temperature at which water boils.
Denys Papin can be counted the inventor of this, in 1679, when he demonstrated his digester to the Royal Society. It rendered bones soft and gelatinous; his machine was also the inspiration for early steam engines. The modern domestic pressure cooker developed out of much larger ones used in the canning industry. They were adopted for the home when small-scale canning was more widespread. By the 1920s, cast aluminium saucepans such as are familiar today were being offered for general cookery. A pressure valve reduced the risk of explosion, but this was never far distant until more satisfactory designs were perfected in the 1950s. The device permits much faster cooking, and may destroy more bacteria due to the high temperatures reached. The advantage of greater speed was harnessed by Colonel Sanders in the 1930s to convert his Kentucky fried chicken into an international fast food (the joints are cooked under pressure).
