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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?

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Food

Why bread dough rises

The holes in a slice of bread are a record of what happened inside the dough. In ordinary yeast-raised wheat bread, making gas is only part of the story: the dough also has to hold it.

3–5 min

Why bread dough rises

Food3–5 minThe holes in a slice of bread are a record of what happened inside the dough. In ordinary yeast-raised wheat bread, making gas is only part of the story: the dough also has to hold it.

Food

How does milk become yogurt?

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?

Food3–5 minYogurt 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.

Food

How does mayonnaise keep oil and water together?

Oil and water separate readily, yet mayonnaise can hold them in a thick mixture. The oil remains in tiny droplets rather than dissolving, and emulsifying components help those droplets stay dispersed.

3–5 min

How does mayonnaise keep oil and water together?

Food3–5 minOil and water separate readily, yet mayonnaise can hold them in a thick mixture. The oil remains in tiny droplets rather than dissolving, and emulsifying components help those droplets stay dispersed.

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