Science Experiments

Dissolving eggs - the power of enzymes

Sun, 16th May 2010

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What you Need

Boiled Egg

A hard boiled egg

Biological washing powder - not one of the 'eco' brands


Jars or glasses

Non-biological washing powder

What to do

Take 3 jars fill all of them with water, and add about a couple of tablespoons of biological washing powder to one and a couple of tablespoons to another, and leave the third as a control with just water.

Cut the white of the hard boiled egg into lumps of about the same size or thickness. I ended up using slices about 5mm thick.

Egg at start

Put a lump into each jar and leave them for 2-3 days somewhere as warm as you can find, 40C is ideal.

Is there any difference between the bits of egg?



What may happen

You should find that the egg in the water has hardly changed and the egg in the biological washing powder is significantly smaller than it started, particularly at the corners which become very curved.


Egg in ecover non-bio

The egg in non-biological powder is essentially unchanged - the corners are still sharp.

Egg in tesco bio

The 'eco' biological powder seems to have had very little effect.

Egg in Ariel

However the conventional biological powder has eaten away all the sharp edges.

Egg in coop bio

The own brand biological powder does seem to have eaten away at the egg, but in a slightly different way



Why does it happen?

One of the hardest stains to remove from clothes conventionally are long molecules that have dried on, such as proteins and fats. The problem is that the long molecules tangle together and are very hard to dissolve and remove from the clothing fibres.

One solution that the washing powder manufacturers have come up with is to add enzymes to the powder. Enzymes are biological catalysts, molecules assist chemical reactions and make them occur much faster and more easily without being used up themselves. Each enzyme molecule can catalyze thousands of reactions. There are a variety of enzymes in the washing powder which catalyze the break up of fats, starches or proteins.


Egg white

Enzyme attacking egg whte

Egg white is made up of long tangled protein molecules so doesn't dissolve. well

The protease enzyme acts to cut up the egg white proteins making the fragments soluble, so they just dissolve.

The egg white is made up of proteins so will be broken up by a washing powder with enzymes to break up proteins (proteases). Not all washing powders use the same enzyme and different brands may add different amounts of enzyme, so they don't all work as well as one another.

Dave Ansell


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