Yeast

Yeast is a type of fungus that reproduces by budding or fragmentation. Yeast cells have a cell wall made of chitin, similar to insects and crustaceans. Some species of yeast are pathogenic, causing infections in humans and animals Yeast fermentation produces carbon dioxide gas, responsible for beer's foaminess Yeast is used as a biological control agent in winemaking to clarify juice and prevent spoilage