The Lemon Fool

We were given one a while back and it is a Russell Hobbs Chalkboard cooker.

We have tried about twenty recipes and in all cases the food cooked in about half the suggested time, even on Low as always.

The liquid is often bubbling and the temperature is 99 degrees C. I.e boiling not simmering.

Surely it is not right to be this hot?

I too just bought a slow cooker, but mine is a cheapo "Crockpot" brand.

To my surprise also, mine too gets the contents actually boiling around the edges even on "Low" setting. I'm sure the slow cooker we had 25 years ago didn't do this but kept it just below boiling - the whole point of a slow cooker originally IIRC.

I suspect consumer demand has led to this. No bubbles from boiling results in them being sent back as supposedly not working.

Google it!

https://chefspick.co.uk/slow-cooker-tem ... B0C%20mark.

"When set to ‘low’, the internal temperature of the slow cooker reaches around 90°C. On the other hand, the ‘high’ setting will see the internal temperature rise to around 150°C."

monabri wrote:Google it!

https://chefspick.co.uk/slow-cooker-tem ... B0C%20mark.

"When set to ‘low’, the internal temperature of the slow cooker reaches around 90°C. On the other hand, the ‘high’ setting will see the internal temperature rise to around 150°C."

Self-evidently rubbish I'd have thought!

How can 'internal temperature' of the contents rise to 150C, 50C above boiling point, without a corresponding and enabling rise in pressure?

This might shed some light.

https://www.thespruceeats.com/are-hotte ... bad-479985

I made a "Haybox" years ago using polystyrene. For those who don't know it's a somewhat agricultural slow cooker. Get pot and contents up to boiling then place in very well insulated container. Should be good and ready in about 8 hours. Safety depends upon time and insulation.

https://en.wikipedia.org/wiki/Haybox

Our RH cooker is 200 watts. Some are as low as 130. Many are 160.

Today,s ratatoille cooked well in 3 hours - recipe provided says 6-8 hours on low! Ratatuoille Soup anyone?

Isn't the point of a slow cooker to use it for stuff that can be left to cook more-or-less indefinitely? Mine tends to get used for broths and soups, and doesn't emit steam.

Today I was out from a little before noon for 8+ hours. I did my cooking in the morning, and left the slow cooker brewing (on low). Don't know how hot it gets, but the tomato and basil soup (which I've just eaten) was delicious, and of course there's plenty left for the fridge and freezer once it's cooled. It could've been brewed in a big cauldron on the hob in a small fraction of the time, but takes on an even richer flavour slow-cooked.

UncleEbenezer wrote:Isn't the point of a slow cooker to use it for stuff that can be left to cook more-or-less indefinitely?

Yes it is, but if you read the links you'll see the manus have been running scared of being sued by stupids who put frozen meat in them then get food poisoning, so they raised the temp of new slow cookers so they boil in about 2006.

General idea now seems to be to buy an ancient one in a charity shop, made before the design was modified to make them 'safe'.

And looking on ebay, it looks as though this is a well known problem. Old slow cookers form the 1970s are often highlighted as "vintage" and seem to command a price premium.

Mike4 wrote:

UncleEbenezer wrote:Isn't the point of a slow cooker to use it for stuff that can be left to cook more-or-less indefinitely?

Yes it is, but if you read the links you'll see the manus have been running scared of being sued by stupids who put frozen meat in them then get food poisoning, so they raised the temp of new slow cookers so they boil in about 2006.

General idea now seems to be to buy an ancient one in a charity shop, made before the design was modified to make them 'safe'.

That seems at odds with my experience.

My slow cooker is (one function of) a Ninja Foodi. Can't remember exactly when I bought it, but it was new since moving here - the address where I've lived since 2019. I don't know how hot it gets, but it certainly doesn't visibly steam (on slow-cook setting) as a pan or kettle does when boiled.

UncleEbenezer wrote:

Mike4 wrote:

Yes it is, but if you read the links you'll see the manus have been running scared of being sued by stupids who put frozen meat in them then get food poisoning, so they raised the temp of new slow cookers so they boil in about 2006.

General idea now seems to be to buy an ancient one in a charity shop, made before the design was modified to make them 'safe'.

That seems at odds with my experience.

My slow cooker is (one function of) a Ninja Foodi. Can't remember exactly when I bought it, but it was new since moving here - the address where I've lived since 2019. I don't know how hot it gets, but it certainly doesn't visibly steam (on slow-cook setting) as a pan or kettle does when boiled.

I'm just measuring mine now. Filled with hot water and on the "high" setting, it is now up to 96.9C according to my digital cook's thermometer

Update:
It's just started boiling properly, just like a saucepan on a hob. Temp according to my cook's thermometer: 102.4C !

feder1 wrote:We were given one a while back and it is a Russell Hobbs Chalkboard cooker.

We have tried about twenty recipes and in all cases the food cooked in about half the suggested time, even on Low as always.

The liquid is often bubbling and the temperature is 99 degrees C. I.e boiling not simmering.

Surely it is not right to be this hot?

I have exactly the same slow cooker (one of these - https://uk.russellhobbs.com/chalkboard- ... oker-24180) and when left on I wouldn't say the contents are "bubbling" but with the steam collecting under the glass lid then it is certainly warm.

How full is it when you are using it? When we use ours then it is almost full, and would using it with a smaller quantity make a difference?

Also you say the food is cooked in about half the time, but there is 'cooked' and 'cooked'. When cooking things like a bolognese sauce or a chilli you could say it was 'done' after 3 hours, but after leaving it for another 3 hours then it will have changed dramatically to produce what I would say is what is expected from a slow cooker.

Can I recommend that a thermometer like this

https://www.amazon.co.uk/flintronic-The ... 117&sr=8-5

will aid to the discussion as well as aid in other things. I found that a sugar thermometer made a huge difference when I made jam.

Ps quantities and Wattage should only change how quick things happen, not the temperature.

Maybe add an external temperature control (basically, use a dimmer).

From memory, using triacs for stuff like this was much more effective (and efficient and possibly safer....) than simply adding an inline rheostat, but I have no idea how modern dimmers work.

So just a suggestion for further investigation. Please DYOR!

https://vaporbaker.wordpress.com/2010/06/28/how-to-make-and-use-a-slow-cooker-temperature-control/

Mike4 wrote:

UncleEbenezer wrote:Isn't the point of a slow cooker to use it for stuff that can be left to cook more-or-less indefinitely?

Yes it is, but if you read the links you'll see the manus have been running scared of being sued by stupids who put frozen meat in them then get food poisoning, so they raised the temp of new slow cookers so they boil in about 2006.

There should be a catch-all law preventing the stupid from suing for the consequences of their stupidity.

We had a slow cooker in the 70s. After 8-10 hours typically came home to lukewarm and sometimes not really cooked, so we sold it.

The pressure cooker made them an irrelevance for us long ago, but I would think one could be useful as a sort of permanent stockpot.

V8

A quick Google reveals that a "trailing edge dimmer" is based on Triacs (or whatever they are called these days) and should be safe and efficient with a slow cooker.

A version suitable for 100 W LEDs should be able to handle 1000 W but do check! ("The 10% rule" over rates dimmers by a factor of 10 when using for LEDs).

Urbandreamer wrote:Can I recommend that a thermometer like this

https://www.amazon.co.uk/flintronic-The ... 117&sr=8-5

will aid to the discussion as well as aid in other things. I found that a sugar thermometer made a huge difference when I made jam.

Ps quantities and Wattage should only change how quick things happen, not the temperature.

Ha, that is the exact thermometer I have!

My own £15 Crockpot also has a "warm' setting which I discounted as the manual stresses it os only for keeping things warm, not for cooking. But I filled the pot with water at about midnight and set it to "WARM" as an experiment, and this morning, used said thermometer to measure the temperature, it measures 74.9C.

Given these pots are so cheap I think the heater elements are just two short pieces of resistance wire in the base. A different length for each heat of the two lower settings on mine (with them both turned ON for the "High" setting) and no further control mechanisms.

I've turned it up now to the "LOW" setting and I'll see what temp it has gone up to when I get home tonight.( Got a boiler to fix in Cambridge today!)

Oh and is 75C (OK 74.9C) actually hot enough for it to work as an old school slow cooker, does the team think?

Mike4 wrote:Oh and is 75C (OK 74.9C) actually hot enough for it to work as an old school slow cooker, does the team think?

It's how it should work, IF you do things properly.
First get your food up to boiling for 5 to 10 minutes. Then turn it down to warm (75).

You NEED to get most food to that temperature. The 75C is not really hot enough to kill bugs or destroy the toxins in kidney beans.
https://www.dadcooksdinner.com/slow-coo ... poisoning/

BTW, if you look up pulled pork, many recommend an internal temperature of 75C (in F). Hence as long as you get the outside hot enough to kill surface bugs you are good to go.

With respect to my last post.

75C is good for most meats. Here is USDA safety advice on temperature (in F, pick the hottest and convert to C, or use the thermometer and think in F).
https://www.usda.gov/media/blog/2011/05 ... mperatures

Remember though that you should get the surface hotter to kill surface bugs.

Looking forward to Mike getting back with the temperature of the "Low" setting.