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Digestible sugars

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Bricktop86
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beers 649 º places 11 º 16:18 Sat 11/10/2012

Hello,

Iím pretty new to home brewing. I was wondering if anyone knew what sugars yeast can digest. By the way I am a chemist so please get scientific if you feel like it.

 
CLevar
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places 16 º 16:29 Sat 11/10/2012

Originally posted by Bricktop86
Hello,

Iím pretty new to home brewing. I was wondering if anyone knew what sugars yeast can digest. By the way I am a chemist so please get scientific if you feel like it.


Depends what species of "yeast" you are talking about....

EDIT: I should have been even more clear, and said "genus"

 
Bricktop86
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beers 649 º places 11 º 16:34 Sat 11/10/2012

If its possible to give me some type of chart that would be perfect.

 
Quasimodo
beers 217 º 16:57 Sat 11/10/2012

It would be easier to say which sugars arenít easily fermentable. Lactose is one of them, but even that is fermentable if lactobacillus is present. Common sugar sources used in brewing: table sugar, invert sugar, brown sugar, molasses, rock candi sugar, candi syrup, turbinado sugar, fruit, grain, honey, maple syrup, agave and more.

 
CLevar
premium
places 16 º 17:13 Sat 11/10/2012
 
tronraner
beers 2459 º places 109 º 17:14 Sat 11/10/2012

Originally posted by Bricktop86
Hello,

Iím pretty new to home brewing. I was wondering if anyone knew what sugars yeast can digest. By the way I am a chemist so please get scientific if you feel like it.


quoting _Brewing_ by Lewis and Young:

"The fermentable sugars in brewerís wort are maltose, maltotriose, and lesser amounts of sucrose, glucose, and fructose. The trisaccharide maltotriose and disaccharide maltose are transported into the cell and hydrolyzed to glucose. Sucrose is hydrolyzed outside the cell to its constituents glucose and fructose."

This refers to Saccharomyces cerevisiae. Different strains vary in their abilities to ferment maltotriose.

And other genera of yeast, e.g. Brettanomyces, can ferment more complex sugars.

 
Quasimodo
beers 217 º 17:35 Sat 11/10/2012

Just being curious here. Why do you want to know this?

 
OldSock
12:12 Thu 11/15/2012

Originally posted by Quasimodo
It would be easier to say which sugars arenít easily fermentable. Lactose is one of them, but even that is fermentable if lactobacillus is present.


And certain strains of Brettanomyces, another yeast.

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