For a preview of our next few blogs about myths, see our march 3-14 blog on 5 000 year old yeast!
Myth #1 Yeast is all the same
Absolutely not! Now that was simple. The explanation is more complex, books have been written on the subject. But, here are a few glimpses. There are over 1500 types of yeast out there, in nature and "bred" for specific purposes.
Wild yeast is everywhere. In the old days, Greeks and Romans etc would let the grapes ferment with the "natural yeast" present on the skins. A hit and miss proposition ending up with good wine at times and totally rank at others.
Our kits come with the "bred" Lalvin 1118 yeast – made for its purpose and very reliable. There is also Lalvin 1116, meant for home made fruit wines other than grape. There are many others as all of them are bred for a specific purpose – imparting taste for example.
Bread yeast: As it says, for bread. It's purpose is to produce CO2 to leaven the bread dough. Otherwise with no leavening, you get flat-bread. Can it be used to make home made wine? Yes, sort of. It is still used but because it does not tolerate alcohol very well, it will be killed off at 6-7% resulting in a sweet and low alcohol wine.
Vinegar Yeast: Again as it says, it is bred to produce vinegar. Where as lalvin yeast feeds on sugar, vinegar yeast (aceto bacter) feeds on alcohol. Not even close in purpose. Remember the comment above about "natural yeast"? It to is present everywhere. It preys on the alcohol in wine or beer after other yeasts had done their work. No wonder the old timers sometimes say "Mama mia, 2004 was a bad year".
High alcohol yeast: Bred to tolerate a higher alcohol content (20-22%) Usually the intent is to distill the alcohol to take advantage of a higher volume of sugar.
Beer yeast: Same story. Meant to ferment wort into beer. Usually they tolerate 5-7% alcohol but some are more alcohol tolerant. The Belgians are good at it.
Some beer yeasts are bottom fermenting meaning less oxygen and a cooler temperature (ex Lagers). Others are top fermenting, the opposite and will result in ales, very British.
I could go on but then, there is always Google!