Another

random recipe?
TrafficRating
  • Already noted 5 times
  • Average note : 1.8/3





Recipes

Introduction

Cooking abounds with old sayings and proverbs, which are sometimes useful tips and sometimes myths. We learn or hear them somewhere, and often trust them completely, even when they're wrong.

I propose simply to verify them, to see whether they are real useful tips that we can use, or just ill-founded popular beliefs.

Of course I can't claim to be writing scientific facts here, just personal observations and what I understand them to mean.

The belief

"One should always cover a pan while heating, so that it boils faster."

In other words, if you heat water (or something else), it comes to the boil faster with a lid on the pan than without.

The approach

We are going to heat 1 litre of water in an uncovered pan and measure the time it takes to boil , then another litre in a covered pan, heated and measured in the same way.

Comparing these times will tell us if it is really necessary to cover the pan.


The result in brief

"One should always cover a pan while heating, so that it boils faster." : false.



Let's check this:

1 litre of water is measured and poured into a pan without the lid and put on the hob with a thermometer in it.

Starting temperature of water (and room): 70°F (19°C).

One should cover a pan while heating : Photo of step #1
The heat is switched on. The water reaches 210°F (100°C) in 9 minutes and 30 seconds.
One should cover a pan while heating : Photo of step #2
The hob is left to cool for about one hour, to allow it to reach room temperature again.

Another 1 litre water is put in the same pan covered with the same thermometer in it, on the same hob.

Starting temperature of water (and room): 70°F (19°C).

One should cover a pan while heating : Photo of step #3
The heat is switched on. The water reaches 210°F (100°C) in 9 minutes and 27 seconds.
One should cover a pan while heating : Photo of step #4
The result is shown more clearly in the diagram: the temperature of the uncovered pan in red and that of the covered pan in green.
One should cover a pan while heating : Photo of step #5

Results

The time difference is too small to be significant. It really doesn't matter whether the pan is covered or not.

Last modified on: February 21th 2011

Back to top of page



You might also like:


Your comments or questions on this recipe:

- - -

This is going to be a most interesting addition to your site, jh. Now I wonder if hot water or cold water makes any difference in the boiling time?

Comment #1 posted on october 24th 2009 at 17:48 by Louise.


Post a comment or question:

You are welcome, if you wish, to comment on this recipe: why you like it or not, what you have changed, what results it gave, point out a mistake or omission, etc. You can also ask a question. I answer all questions (in a broken English, sorry) unless someone else does it before me.
Please feel free to say what you think, I'm always very interested in your opinion. Your comment will appear on line with the recipe, so please write in standard readable English, not SIM or only in CAPITALS, otherwise your comment may be rejected.

Please look at advice for submitting a comment or image (what you should or should not do). By the way, don't type your e-mail address in the comment, otherwise you might be spammed.

Your first name or pseudo: (optional).

Please check/tick this box to show that you are a real human being (protection against Spam)*.


I am not a leaving thing

You can also get a RSS feed on last comments of this recipe.

Back to top of page


Follow this recipe

If you are interested in this recipe, you can "follow", ie you enter here your e-mail address, and then each time the recipe is modified, or commented, you will immediately receive a personal e-mail to warn you.
Note: You will need to confirm that you want to follow this recipe.
My e-mail address is:

Please check/tick this box to show that you are a real human being (protection against Spam).


I am not a leaving thing