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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

Questions you could explore

  • What do the starter bacteria produce from lactose?
  • How does acidification change the milk?

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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 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.

Food

What two plants can a fruit tree contain?

The roots and the fruiting branches of a grafted tree can come from different plants. Growers choose a rootstock and a scion for different jobs, joining them without creating the same kind of new plant as a seed cross.

3–5 min

What two plants can a fruit tree contain?

Food3–5 minThe roots and the fruiting branches of a grafted tree can come from different plants. Growers choose a rootstock and a scion for different jobs, joining them without creating the same kind of new plant as a seed cross.

How does milk become yogurt? | Speech Topic | speaking.app