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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

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.

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