Bakers have used yeast to make bread for millennia! We now know why it works and how a little sweetness goes a long way.
Safety:
When dealing with food, use clean hands and clean equipment. Be careful when using the oven by wearing oven mitts and ask an adult to help you out.
Combine 2 cups of flour with the yeast, sugar, and salt in a large mixing bowl.
To get the water to a nice temperature for yeast, set your tap on the warmest setting and let it run into another mixing bowl. Dip your fingers into the bowl holding the running water until it feels comfortably warm, but not hot enough to burn you. Ask an adult to help if you need. Mix in the warm water and oil to your dry ingredients (you can use your hands). Your dough mixture should get sticky!
Add the remaining ½ cup of flour bit by bit, mixing as you go, until the dough is no longer sticky. You may not need all the remaining flour.
Knead the dough on the chopping board for about 3 minutes until it becomes elastic and smooth. If it gets sticky again, you might need to add a little extra flour. You might also like to take turns with someone if you get tired. Check out the steps for kneading dough in the infographic after Step 8.
Put the dough back in the large bowl and cover with the tea towel. Let it rise for about half an hour. Meanwhile, pre-heat your oven to 200°C.
Punch the dough down and mould it into a shape that will fit in the oiled loaf pan.
Bake at 200°C for 40 minutes.
Let it cool for about 10 minutes, then slice and serve with butter. What flavours do you notice?
Unlike all the other ingredients, yeast is alive! The yeast you added to your dough are single-celled microorganisms related to fungi (like mushrooms). In fact, the first two steps of our recipe are all about giving yeast an ideal environment: sugar to eat and warm water to thrive in.
As the yeast feeds off the sugar, they belch out warm carbon dioxide gas. This warm, expanding gas gets trapped in the dough mixture and causes it to rise! The dough keeps on rising as the yeast break down the sugary starches in the flour.
To understand how the dough can rise without breaking, we knead to talk about gluten. Gluten is made from proteins found in grains like wheat. At first, gluten proteins are disorganized and tangled like string. Adding water untangles them while mixing and kneading organizes the gluten into springy webs called sheets. These gluten sheets give bread its elasticity and its ability to hold a shape.
Try a plain bite or two of your yeasty bread, close your eyes, and focus on what you taste! Be your own food critic and write down your observations.
Did you detect earthy, savoury flavours? When you left your dough to rise, the yeast was busy converting sugars into carbon dioxide through a process called fermentation, adding earthy flavours to your dough. As living organisms, yeasts also generate other by-products that give bread extra flavours. Because of all these flavourful by-products, many bakers let their breads rise for hours or even days!
Did you detect saltiness? Salt is a mineral important for brain and nervous system’s functions. As a result, our taste buds are sensitive to salt, which evolved millions – if not billions – of years ago to ensure our ancestors ate enough salt.
What else do you taste? Food is chemistry – and biology – you can eat!
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