15-minute experiment

Green beans with and without an ice bath

Q: What does the green beans with and without an ice bath experiment test?

It tests one variable: ice bath or not. The idea is that green beans plunged into ice water stay bright and crisp. Beans left to cool on their own turn dull and soft.

Bright green isn't an accident.

The idea

Green beans plunged into ice water stay bright and crisp. Beans left to cool on their own turn dull and soft.

The one thing you change: Ice bath or not

You need

200 g green beans, trimmed and split in two
A pot of boiling salted water
A bowl of ice water
A plate

Steps

Boil all the beans for 2 minutes.
Lift half out with a slotted spoon into the ice water and the other half onto a plate. The cooking water is scalding.
After 5 minutes, drain the iced beans. Compare the color, then bite one of each.

What you should find

The iced beans are bright green and snappy. The plate beans are olive and softer.

From the app

Cook this with Chef Fizz

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The science behind it

Blanch and shock vegetables

Drop green vegetables into well-salted boiling water for 1 to 3 minutes, then straight into ice water. The brief heat drives out trapped air so the green…

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