

Some like it hot, some like it cold, but yeast likes it just right!
Things Required:
2/3 cup (160 ml) of warm water
2 tablespoonfuls of sugar
1 package of dry yeast
3 mixing bowls (or cereal dishes)
Plastic chopping board
A felt-tipped pen, paper, scotch tape
3½ cups (392 g) of flour
2 tablespoonfuls (30 ml) of oil (olive or corn oil) 150 ml of water
Pinch of salt
1 teaspoonful of oil (to oil bowls)
A wooden spoon
Plastic wrap
Directions:
Dissolve the sugar and yeast in cup (160 ml) of water that is warm to the touch. Let the mixture stand. Mix flour, salt, oil and 5 ounces (150 ml) of water.
When bubbles appear on the surface of the yeast mixture, add it to the flour and mix well with a wooden spoon, or in a mixer. Knead the dough on the chopping board for five to 10 minutes. Sprinkle on more flour if the dough gets too sticky to handle. Keep pushing against the ball of dough, pressing into it and turning it to knead it on all sides.
When the dough feels satiny, make it into a ball and divide it in three equal parts. Place each part in an oiled bowl covered with plastic wrap. Number the samples. Place number 1 in a warm place (without a draft). Place number 2 in the warmest part of the refrigerator. Place number 3 in a hot place-over a radiator or in a hot oven.
Let them stand. Observe them after the first hour and then after several hours.
This Is What Happens:
Within 45 minutes to an hour, the dough in a warm place doubles in size. The dough in the refrigerator eventually rises, too, but it takes much longer. The dough in the hot place does not rise at all.
Science Behind It:
Yeast requires a moist, warm temperature, above 50° and below 130°F (10°-54°C). Below 50°F (10°C), it is relatively inactive, and above 130°F (54°C), it dies of too much heat.