How to boil the perfect egg: use thermochromic ink, of course

Tech Digest news

Scientists have been working on something which is, apparently, a big problem – perfectly boiling an egg.

Yes folks, forget the humble egg timer, or intuition: if you really want to know when your egg is cooked to perfection, you need ‘thermochromic’ invisible ink, which turns dark when it reaches a certain temperature.

According to Lion Quality Eggs, who launched the project, thousands of
people have been asking how to boil an egg properly, and so B&H
Colour Change came up with this techie solution.

Inks have been developed which change colour after 3, 4 or 7 minutes –
for soft, medium, and hard boiled eggs. They’ve even been promised on
supermarket shelves soon – so not only will you be able to choose size,
organic, free range, etc. but also how you like them cooked. I suppose
you’ll have to go back to guesswork if you want to soft boil half the
eggs and hard boil the other half.

This is just one application in the development of heat-sensitive
, which could also be used for talking oven gloves,
colour-changing fire doors, sports clothing that can tell when a person
is overheating (I thought we had that in the 90s?), or road signs that
respond to road conditions.

Modern science, eh?


Andy Merrett
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