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Why can frozen food still contain living microorganisms?

Freezing can suppress microbial growth without killing every microorganism. When conditions change after thawing, surviving organisms can become active again, so freezing does not erase a food's handling history.

3–5 min

Questions you could explore

  • How is preventing growth different from sterilizing?
  • Why does what happened before freezing still matter?

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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.

Why can frozen food still contain living microorganisms? | Speech Topic | speaking.app