Pressure Cookers & Denis Papin

[MULTIZ321]

- Denis Papin's Pressure Cooker

The man who gave us the pressure cooker, Denis Papin, was born on this date in 1647.

The French physicist and mathematician was best known for his work with steam power.

He worked closely with Christiaan Huygens, experimenting with the air pump.

Aside from the pressure cooker (which he called the "steam digester"), Papin conceived the idea for the steam engine and built the first human-powered paddle boat.

In 1710, he was appointed to the Royal Society, but many of his ideas and his personality conflicted with those of other members, especially Sir Isaac Newton, the Society's president.

No one seemed to know where Papin spent his final days; the last record of his whereabouts is a letter he wrote, dated January 23, 1712.

It is believed that he died destitute later that year and was buried in an unmarked pauper's grave.

Quote: "The scientist is not a person who gives the right answers, he is one who asks the right questions." — Claude Lévi-Strauss

What is a pressure cooker?

A pressure cooker is a cooking vessel that is enclosed with a lid that seals to the pan with a rubber gasket, which cooks at a pressure that is higher than the atmospheric pressure.

These cookers are usually made of thick-wall stainless steel or thick aluminum.

In the lid is a small vent-hole that contains a pressure-regulating mechanism.

Water in the food being cooked will boil and cause a steam build-up in the vessel, which will increase the pressure inside the vessel.

The pressure-regulating mechanism on the vent-hole will allow some steam out if pressure exceeds a certain limit (usually around 15 psi, or 15 pounds per square inch), thus maintaining a more or less constant pressure inside the pressure cooker that is higher than atmospheric pressure.

Since the boiling point increases with higher pressure (for example, water boils at 100 degrees C at atmospheric pressure but it will boil at a higher temperature inside a pressure cooker since the pressure inside is higher), the temperature inside a pressure cooker can rise more than it would have in an open-enclosure pan.

Because of the higher temperature, meat becomes soft easily and food cooks faster causing less loss of nutrients.

Pressure cookers often have various safety mechanisms to prevent the buildup of excessive pressure and exploding.

After cooking is finished, it is important to release the steam slowly first, because if the lid is opened suddenly, a large amount of steam escaping can cause scalding.

Many pressure cookers have special mechanisms for controlled steam release before opening the lid.


Richard

 

[MuranoJo]

Very timely, for those of us harvesting a garden now!

Those pressure cookers always make me nervous, though they're actually quite safe if used wisely.

Have a friend who's a good cook and uses them a lot for just fixing everyday meals, not just canning. (Meats, beans, rice, etc.)