>> Saturday, January 23, 2010
My husband and I were having a discussion last night about yeast. Odd topic, I know, but it wasn't without reason. I'm on antibiotics at the moment and I was trying to explain to him what thrush was and why I had to eat so much yogurt. He tried to tell me yeast was not a fungus. Ok. Maybe from a culinarian standpoint I could understand, but don't argue with biologists about this sort of thing unless you want this up on the internet the next day. Now onto the science!
What are yeasts?
Simply put, they are single celled fungi (think worlds tiniest mushroom if that helps).
Eww, gross, so they are alive?
YES! That is what makes them so useful. You see, part of what makes yeast so helpful is that it breaks down (think digestion) sugars to ethanol or carbon dioxide gas. Without yeasts, grapes wouldn't be so delicious (the white film on grapes is a yeast) or couldn't turn to wine very well, we wouldn't have yummy leavened bread, there would be no beer or (gasp!) sourdough!
Where do they come from?
Isn't that a universal question? More specifically I guess you could ask where they are found naturally. Then I could tell you that yeasts are found almost everywhere. They live on the skin of warm blooded creatures symbiotically or parasitically, they live on plant leaves and flowers and roots, they live in salt water and soils, and they live in our intestinal tracts. They are one of our closest neighbors!
Can't yeast be bad, too?
Sure, but it's all relative. Many of the "bad" yeasts are actually not harmful in normal situations. Weakened immune systems, medications and age can make it so that your bodies normal bacterial level is thrown off and you end up with various forms of yeast infections. Pretty much what is going on here is that your body has a nice system of checks and balances in place and the lack of bacteria means more room for yeast and it is more of a nuisance than anything. In some extreme cases it can cause intestinal "parasites" to use the term loosely.
Now you are all caught up on your yeast knowledge! If you have any questions, leave them in the comments... I always reply.
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