The Bread Mold Experiment

The aim of the bread mold experiment is to see what organisms are living on the kitchen bench and compare this to what is picked up from just the air alone.

Materials Needed: You will need the following:

* 2 slices of bread (wholemeal is best)
* cling wrap or sealing sandwich bags
* spray bottle filled with water
* magnifying glass (optional)

Procedure:

Step 1: Wipe one of the two slices of bread on the kitchen bench or any other surface regularly used for food preparation. The second slice acts as a control for the first; it shows what would happen without wiping it on the surface.

Step 2: Spray both slices very lightly with water

Step 3: Seal the slices in separate pieces of cling wrap or separate sandwich bags.

Step 4: Place the wrapped bread slices somewhere warm and wait for the mold to grow. Once the difference between the two slices is significant enough, remove them and inspect the results.

Step 5: Examine the mold colonies with a magnifying glass. Note that caution must be taken not to breathe in the dust from the mold colonies as it can cause medical complications.

What is Happening?

The mold colonies have ended up on the bread either from landing on the bread from the air, or as a result of being collected from the bench in the process of wiping. The difference in the quantity and types of mold present show that wiping the bread on the bench results in far greater mold growth as well as diversity.

Possible Extension: School Activity to Test Disinfectants

This bread mold experiment can be extended to test different brands of disinfectants. Student work benches such as those found in secondary school science laboratories are easily as dirty as a standard kitchen bench.

To test different brands of disinfectants, divide a standard school bench into sections, one for each brand of disinfectant. Clean the bench section in accordance with the instructions on the bottle of disinfectant. Then wipe the treated area with a slice of bread and keep the bread as previously described. Repeat this process for as many different brands of disinfectant as are available.