What are the different kinds of living agents in baking?

There are several types of living organisms used as living agents in baking for various food applications. These include:

1. Yeast: Yeast is a form of fungus, primarily used in baking for leavening. When mixed into a dough, yeast ferments the sugars present and produces carbon dioxide, which creates bubbles and causes the bread or dough to rise.

2. Sourdough Culture: Sourdough is a fermented dough made with a natural yeast culture and lactic acid bacteria. It gives bread a slightly sour flavor and chewy texture. The wild yeasts and bacteria in the sourdough culture are responsible for the fermentation process.

3. Lactic Acid Bacteria: Lactic acid bacteria are involved in the fermentation of many fermented dairy products like yogurt, kefir, and cheese. In baking, they are sometimes added to improve the flavor and texture of certain baked goods, particularly sourdough bread and other naturally fermented breads.

4. Propionic Acid Bacteria: Propionic acid bacteria play an essential role in some dairy fermentations. In baking, they are primarily used for their preservative properties. They convert certain sugars into propionic acid, which inhibits the growth of harmful microorganisms and prolongs the shelf life of baked goods.

5. Mold Cultures: Certain types of mold, such as Aspergillus oryzae and Aspergillus niger, are commonly utilized in Asian cuisines for the manufacturing of fermented food products. In specific traditional baking applications, mold cultures may be used for fermenting soybeans or rice, resulting in ingredients like tempeh or koji.

It's important to use food-grade living agents and handle them hygienically to ensure the safety and quality of baked goods.