What you need:
- Containers that can be sealed e.g. jam jars, zip-lock bags
- Bread - you can also use fruit, vegetables or yoghurt
- Water
How to:
Remember: some moulds are good, such as the
mould in blue cheese. Other moulds can be toxic. If you suffer from
allergies or asthma, we suggest you don't try this experiment as
some moulds can trigger allergic reactions.
- Put half a slice of bread in a zip-lock bag. Sprinkle a bit of
water over the food.
- Leave the bag open for half an hour. After half an hour, seal
the bag.
- Leave the bag in a warm place.
- Check the bag daily. How long does it take the mould to grow?
There should be mould after about a week. You've grown your own
mould! Some supermarket breads take longer to grow mould, as the
bread has preservatives added to it which inhibit mould
growth.
- Once your mould has grown, put the bag in the bin
without opening it.
You can repeat this experiment to test for lots of different
things.
Try using different foods. What foods grow the most mould? Are
all the moulds different?
Try using different amounts of water. Does this affect the
amount of mould that grows?
Try growing mould in different locations. Does this affect the
amount of mould that grows? What do you think causes this - could
it be temperature, sunlight or moisture?
What's happening?
Moulds are a type of fungi. When you leave the bag open, mould
spores enter the bag. All houses have mould spores in - it doesn't
mean that your house is dirty!
When you seal the bag, mould spores grow into fungi that you can
see. Mould grows best in warm, dark and moist conditions.
Although we don't usually want moulds on food, some moulds are
helpful. Yeast is a mould which helps bread to rise. Moulds give us
the flavour of blue cheese - even if it does taste like stinky
feet! Moulds can even help to fight disease. Penicillin, an
antibiotic that can cure many bacterial infections, is produced by
moulds.