Tim's pressure cooker

[Image of Tim's Pressure Cooker]
Breville Electric Express Pressure Cooker

Pressure Cooker

Here is my pressure cooker.

It seems well constructed.

There are three main controls - energy input (top dial), pressure - and a timer (bottom dial) that automatically turns the machine off after a specified time period.

A safety feature prevents the lid from being unlocked while the device is under pressure.

There is a temperature sensor that turns the machine off if it detects from the temperature that it no longer contains any water.

This is my first pressure cooker. Before this I used a steamer. This machine is more controllable than my steamer was.

[Image of Tim's Pressure Cooker]
View from above

At the front of the machine's lid, a large blue button represents the manual steam vent. It can be activated without getting your fingers near the steam.

The steam vent itself is the circular black knob further back - twist this to select between the three available pressure settings - and standard temperature and pressure.

Visible at the top rear is the lid locking mechanism.

The lid clamps firmly on to the bowl - and the bowl slides down into the base.

[Image pot]
View of pot from below

The heating element is attached to the bottom of the bowl. It has electrical contacts that draw power from the base.

The bowl is coated with a non-stick material. It gives the impression of good durability.

[Image of base unit]
Inside the base unit

Inside the base, there's also a manual switch (centre) - which turns off the power when the bowl is not securely in place - and a temperature sensor (top).

At the bottom, power is supplied.

The text above the power contacts reads:

"CAUTION - TO REDUCE THE RISK OF ELECTRIC SHOCK COOK ONLY IN REMOVABLE CONTAINER".

[Image of basket]
Basket

The supplied aluminium basket is too small to be of much use. I have replaced mine with a larger basket.

[Image of trivet]
Trivet

Here is the supplied trivet. It is unexceptional.

Statistics

The capacity is described as by Breville as being 2.75L. It is rated at 1200 Watts. Breville do not say what pressure can be expected to be obtained.

The electrical cable is 103cm long. I suspect this may be too short for some people's tastes.

I suspect this is not the world's fastest pressure cooker. It takes quite a while to come up to pressure - often representing a significant fraction on the total cooking time.

One gripe is that it can take quite a while to depressurise. I tend to open the vent and then leave it alone to vent steam these days.

Large American relatives

This device appears to be related to a cooker for sale in America called the [Farberware FPC400 Programmable Pressure Cooker].

You can see a picture of that model [here].

There are also "FPC600" and "FPC800V" models - with up to double the capacity (see the links at the bottom of this page for more details).

The Breville model has physical dials for controls - instead of touch-sensitive panels - but otherwise appears to be extremely similar. The upper handles are a different shape - and the pressure control seems to have more settings on the Breville model.

However it appears to be lacking some of the computerised features of the American model - no "Delay timer" - which provides a programmable delay before starting, for example.

One feature I would find useful is the ability to heat on full blast until the pressure is up - and then to turn the heat down to a steady simmer - to make sure I don't boil off my water too quickly - and make a teriffic racket.

As it is, I tend to put it on at full throttle - and leave the kitchen door open. When it starts loudly venting steam, I go and turn it down - and sometimes adjust the timer.

Unfortunately, the time dial is not very useful - due to the difficulty of using it at all precisely at small time periods.

Safety

Early pressure cookers acquired a negative reputation - due to concerns about their safety. They had a tendency to get very hot, vent piping-hot steam in an uncontrolled manner - and occasionally explode.

Modern pressure cookers now seem to be pretty safe. The machine here has two safety vents as well as the main steam vent. All three would need to be firmly blocked before there could be an unwanted build-up of pressure inside the machine. Eventually the temperature rise would trigger the safety cut-out.

Also there are a range of features designed to prevent things like the machine being opened while under pressure.

Having said this, I would not want to drop my machine from a significant height while it was under pressure.

I've boiled the pot dry a few times now. No detectable damage has resulted, though.

Cleaning

I found the machine relatively simple and easy to clean.

A small brush is supplied for cleaning inside the pressure vent. Owners of the machine may be interested to learn that this can conveniently be stored underneath the machine - by inserting one of the machine's little rubber feet through the hole in it - which has clearly been designed for this purpose.

Pressure cooking vs steaming

Pressure cooking differs from steaming in a number of ways.

The pressure is kept at around 15 pounds/square-inch (psi) - allowing the temperature of the water to rise to 121° Celcius before turning into steam.

The increased temperature cooks the food more rapidly.

From a health perspective, high temepratures and long cooking times both seem undesirable.

One hazzard of cooking at high temperatures is that food is more likely to be chemically transformed in undesirable ways by the cooking process. For example, acrylamide - the probable human carcinogen - starts to form from potatoes when cooked at around 120° Celcius.

A hazzard of cooking foods for long periods of time is that there is longer period available for chemical reactions to occur. This can result in greater free glutamate content - for example.

There appears to be a trade-off between cooking rapidly and cooking at low temperatures.

A pressure cooker lets you move towards higher temperatures and faster cooking times - if you choose.

While I don't yet properly understand all the pros and cons of pressure cooking vs steaming, it does seem to me that pressure-cooked food tastes better than steamed food.

It seems to be drier when it is done - and generally gives the impression of being less processed.

It may be one of the factors is the way the timer makes it less likely for me to over-cook my food. I need to do more extensive trials using the same equipment but different pressure settings before I can say anything very definite.

Foods that require different cooking times

One of the disadvantages of pressure cooking is that everything necessarily has to be cooked for the same period of time.

It is not practical to put rice on, cook for a while - and then add the broccoli. Everything cooks for the same period of time.

If you are cooking rice in water, then you can boil that for a while first - though this loses the advantages of steaming.

One possible approach is to insulate some foods from direct contact with the steam - by putting them inside pots - or wrapping it in foil.

The idea is to reduce the rate of heat transfer from steam into the food, due to conduction and convection.

While I've not seen this approach discussed much, I've tested it - and it my impression is that it is remarkably effective.

Mashing food

I usually like to pulverise most cooked food before eating it.

Here is the tool I usually use.

[Image of masher]
Masher

It is cheap, quick - and pretty effective.

Price

This machine cost me £56.95. I bought it on [eBay].

Is the additional expense involved in getting an electrical model worth it?

That's difficult to say - but I would definitely buy this particular machine again under similar circumstances.

Links

Studies on the effects of cooking, freezing and canning
Tim Tyler | tim@tt1.org | http://timtyler.org/