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What changes inside an onion when you cut it?

Cutting disrupts onion tissue and allows a sequence of enzyme reactions to produce a volatile tear-inducing compound. The irritation therefore depends on chemistry triggered by damage, not simply a liquid already waiting to squirt out.

4–5 min

Questions you could explore

  • How does disrupting the tissue start the reaction sequence?
  • How does the reaction in a cut onion connect to irritation in the eyes?

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Food

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3–5 min

Why bread dough rises

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Food

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Yogurt begins with milk, but its tang and texture develop as starter bacteria change the mixture. Their use of milk sugar and the resulting acidity connect the microbial activity with what ends up on the spoon.

3–5 min

How does milk become yogurt?

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Food

Keeping oil and water together in mayonnaise

Pour oil and water into a jar, shake them hard, and they will quickly separate back into two layers. Yet mayonnaise stays a thick, stable sauce because vigorous whisking breaks the oil into microscopic droplets, while emulsifiers in the egg yolk coat those droplets and stop them from recombining.

3–5 min

Keeping oil and water together in mayonnaise

Food3–5 minPour oil and water into a jar, shake them hard, and they will quickly separate back into two layers. Yet mayonnaise stays a thick, stable sauce because vigorous whisking breaks the oil into microscopic droplets, while emulsifiers in the egg yolk coat those droplets and stop them from recombining.

What changes inside an onion when you cut it? | Speech Topic | speaking.app