some experiments with yeast
Answers
Explanation:
Mix a packet of active yeast with ¼ cup of warm water and a tsp of sugar in a bowl. After 10 minutes, your child will see the mixture foaming--a sign that the microbes are feeding and producing carbon dioxide. Talk about the role those CO2 bubbles play in making dough rise!
Answer:
Materials
Bowl
Warm water
Active dry bread yeast
Sugar
Balloon
Bottle
Tooth Pick
Glass microscope slide
Plastic cover slips
See information on suppliers here.
Methods
Put a pack of yeast in a bowl.
Add warm water and 2 tablespoons sugar and mix with a spoon.
Transfer the mixture into a bottle.
Place a balloon around the bottle neck and wait approx. 10min, during which time the balloon should inflate due to the released carbon dioxide gas.
Wine is made by fermentation of the sugars in the grapes by yeasts that live on them.
To observe the yeast under the microscope:
Place a drop of the yeast mixture on the microscope slide (it might be necessary to dilute it a bit more with water).
Place a coverslip on top and observe under different magnifications. High magnifications will be needed to see the yeast well.