Last week, children in Asia class found out about different types of microorganisms as part of their science learning. We watched a video about what is best to give yeast to make it produce carbon dioxide (out of oil, salt, flour, sugar and a cookie, the sweetness of sugar and cookie worked best!) then designed our own experiments.
Some of us tried testing different liquids (such as lemonade, orange juice and fizzy orange), some compared the natural sugars of strawberries, blueberries and raspberries, whilst others experimented with something a little different: finding out whether using different temperatures of water changed how yeast reacted.
We put yeast, water and the food in zip lock bags, left them for a few hours then came back later in the day to find out what happened. In cases where the yeast produced carbon dioxide, we could see bubbles forming inside the bags. Some foods were particularly effective, such as sherbet and fizzy orange – their bags were puffed up almost to bursting point! The group who tested different water temperatures found that the yeast didn’t activate well at all with water that was too hot or too cold, but, like Goldilocks, the warm water was ‘just right’!