Those who observe or study may have known these following facts about yeast since it’s very important species in kingdom fungi. Yeast, as some people know, is eukaryotic microorganisms classified in the kingdom Fungi, with 1,500 species currently described. Yeasts are unicellular, although some species with yeast forms may become multicellular through the formation of strings of connected budding cells known as pseudohyphae, of false hyphae, as seen in most molds. To get to know more about them, here are some other facts about yeasts you may consider useful.
Facts about Yeast 1: Over than 500 Species
There are more than 500 species of yeast. Brewer’s yeast is just one of 500 species, but within a single species there can be literally thousands of genetically distinct strains. Saccharomyces cervisiae is the species in which brewer’s yeast is classified (cervisiae is the species name).
Facts about Yeast 2: Beer Flavor and Aroma
Yeast contribute more than 600 flavor and aroma compounds to finished beer. Most of these hover around perceivable values, so slight changes in conditions or ingredients can affect flavor profiles. In addition, what compounds yeast do not make themselves, they can affect.
Facts about Yeast 3: Dried Yeast
The Romans discovered the uses of dried yeast, before the discovery of yeast. Yeast grows and lives in liquid. For storage purposes it can also be dried once grown. The Romans discovered how to do this when they put baker’s yeast (dough) in the sun and could later revive it with sugar. Today, most yeast used in the bread and wine industry is in dry form.
Facts about Yeast 4: Worth-waiting
When sweet wort is pitched with yeast, there is a characteristic lag phase before signs of fermentation are evident. This lag phase is an important part of the fermentation process. It can last anywhere from one to 24 hours, depending on the quantity of yeast pitched, fermentation temperature, and oxygen content of wort.
Facts about Yeast 5: Alcohol and CO2
Yeast transform sugar into alcohol and CO2. Attenuation is the percentage of sugars that yeast consume during fermentation; sugars are transformed into alcohol and carbon dioxide. A 100 percent attenuation would result if a beer fermented all the way down to 1.000 final gravity (FG).
Facts about Yeast 6: Flocculation
Flocculation is the special ability of brewer’s yeast to clump together following the end of fermentation and either rise to the surface or fall to the bottom of the fermenter, allowing easy removal from the beer. Most species of yeast are not flocculent. It is thought the reason brewer’s yeast is flocculent is the natural selection process that has taken place in brewing, dating back hundreds of years.
Facts about Yeast 7: Keeping Warm
As the temperature of a fermentation rises, more yeast growth occurs, and consequently more esters are produced. At 90° F yeast produce so much acetaldehyde (which tastes like apples) that the beer becomes undrinkable.
Facts about Yeast 8: Nutrition and Growth
Yeasts are chemoorganotrophs, as they use organic compounds as a source of energy and do not require sunlight to grow. Carbon is obtained mostly from hexose sugars, such as glucose and fructose, or disaccharides such as sucrose and maltose. Some species can metabolize pentose sugars such as ribose, alcohols and organic acids.
Facts about Yeast 9: Reproduction
Facts about Yeast 10: Uses
The useful physiological properties of yeast have led to their use in the field of biotechnology. Fermentation of sugars by yeast is the oldest and largest application of this technology.
Hopefully those who are doing some research about yeast would find these yeast facts really useful and interesting.