There was a time when packaged yeast was not sold in stores. Until people figured out how to grow, harvest, and store yeast in packaging that could be placed on a shelf and activated when needed, they had to rely on using sourdough to make leavened bread. Yeast is a living organism that, under the right conditions, i.e. heat, humidity and a food source such as sugar, ferments and releases carbon dioxide, which raises the bread dough. If yeast is not supported, it is not suitable for making bread.

Today yeast is available at grocery stores in small packages or cans. He is kept dormant until needed for baking bread. In ancient times, people maintained yeast in a so-called starter culture or starter culture. While we can go to the store and buy pre-made yeast in a recipe, the flavor that sourdough gives the bread is characteristic and often desirable. It is best known that sourdough bread Singapore is prepared using sourdough.

Sourdough is a yeast culture containing water, flour and sugar. Here’s how to make your own starter yeast culture. Soften an ounce bag of dry yeast in half a glass of warm water for about ten minutes. Use a glass or plastic mixing bowl and add the softened yeast to one and a half cups of warm water, 2 cups of bread flour, and a tablespoon of sugar. Whisk the mixture until smooth.

Then cover the bowl with a tea towel. It’s important not to use an airtight lid, as yeast needs air to breathe, just like you and me. Leave the mixture on for four to five days, stirring several times a day. As the yeast rises and begins to ferment, the mixture will bubble. Alternatively, starter cultures can be purchased at specialty stores or supermarkets. These cultures start out as a dry mix to which bottled water is added.

Since yeast is a living organism, it is very important to use cookware and ingredients that keep it alive. Use bottled water to prevent contaminants such as chlorine or iron from damaging the yeast you are trying to grow. Use plastic or wooden spoons to stir the mixture. Metal spoons and bowls, such as copper and aluminum, can be toxic to yeast.

Recipes usually require a cup of the main course. After measuring out a cup, add to the dish a glass of water, a bread glass of bread flour, and a teaspoon of sugar. Stir and let stand at room temperature at least overnight. The main course can be refrigerated for up to ten days. Bring to room temperature before using in recipe. If the starter turns orange, discard it and start over.