Biology · GCSE · Human Body Systems

Food tests

Food testsFree3:50Heddy Score 3 of 7, below the standard
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What you need to know

  • Iodine solution is the test for starch and turns blue-black when starch is present.
  • Biuret reagent is the test for protein and turns purple if protein is present.
  • Benedict's solution is heated to test for reducing sugars, changing from blue towards brick red if they are present.
  • Fats are tested with ethanol; a milky emulsion shows that fat is present.

In this clip

Runs 3:50, from 0:00 to 3:50 of the full video.

Heddy Score3/7, Below the standard
See the seven stars
  • Trusted source · passed. The creator's own upload, live and playable here.
  • On the map · not judged yet. A teacher watched it: it mainly teaches this map topic.
  • Spec-true · not judged yet. Accurate, and right for the current UK specification.
  • Focused · passed. One idea, short enough to watch in one go.
  • Accessible · passed. Good captions, clear sound and pictures.
  • Safe for children · not judged yet. Right for 11 to 16 year olds, with no sales pitch.
  • Proven · not judged yet. Earned from our students: they learn from it, find it helpful and watch it to the end.
★ passed · ☆ pending · ✕ failed
Our students

Not enough students yet

Our own students' answers. These are what move ★7 Proven.
On YouTube

1.07M views · 10.7K likes · Science Sauce 125K subscribers

As reported by YouTube on 2026-11-02. Not part of the Heddy Score.
How the Heddy Score works

Why we picked it

It demonstrates the colour changes for starch, protein, reducing sugar and fat, which is the food-test practical.

Science Sauce on YouTubechecked 2026-10-18

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