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Pasteurization needs a time as well as a temperature

If a recipe or food-safety rule simply said 'heat milk to 72°C to pasteurize it,' it would leave out a critical half of the science. Killing harmful microbes depends on both temperature and exposure time working together: validated combinations of a lower temperature for longer or a higher temperature for less time can meet a pasteurization standard.

3–5 min

Questions you could explore

  • Why is a temperature without an exposure time an incomplete description?
  • How can contamination after treatment change the outcome?

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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.

Pasteurization needs a time as well as a temperature | Speech Topic | speaking.app