Ratio of fermenting sugars

[Silviakitty]

This may be a dumb question, but I'm curious (and my searching hasn't found me my answer, though I may be using the wrong terms to search with).

When dealing with sugars in brewing, is it basically a pound is a pound is a pound for fermentables?

For example, a pound of honey, a pound of cane sugar, a pound of fructose...is it all equal in a recipe?

 

[Yooper]

Well, I don't really know. But my honest answer is "I think so". I think basic simple sugars (glucose, sucrose, etc) are all the same as far as beer and wine yeast are concerned.


Well, except for my "excepts".........................I think honey has some water, so pound for pound is not the same. So, maybe it would be the same as far as fermentation, but you'd have to know the water content of the honey. Otherwise, sugar is sugar, I think. At least with fructose, dextrose, sucrose, etc.

Why lactose is not fermentable is beyond my Chemistry 101, though!

 

[eriktlupus]

lactose is a long chain sugar that needs mechanical breakdown for yeasts to consume. glucose fructose and succrose are short chains

 

[Yuri_Rage]

A pound is a pound...sorta.

I just plugged a pound of all of these ingredients into BeerSmith one gallon recipes. Here are the respective SGs:

Light DME: 1.044
Corn sugar: 1.046
Table sugar: 1.046
Brown sugar: 1.046
Clear Candi Sugar: 1.036

Light LME: 1.038
Honey: 1.035
Corn Syrup: 1.036
Molasses: 1.036
Maple Syrup: 1.030

So, the SGs are fairly constant if you substitute a pound of one dry ingredient for a pound of another, and the same goes for the liquid ingredients. However, fermentability may change a bit. For example, dextrose is 100% fermentable since it's a pure sugar. However, brown sugar will probably not ferment nearly as completely because it contains compounds other than sugar. The same comparison could be made with corn syrup vs molasses.

 

[Silviakitty]

Thank you for the answers and the ratio numbers. That makes sense. I've got some fructose and some honey I'm thinking of trying out in some apfelwein, and was wondering how to swing it.

Thanks again.