KelliWhite: Sweetness In Wine

Very interesting article by KelliWhite, as linked by WineTerroirist, in GuildSomm:
SugarInWine .

It discusses the importance of the glucose/fructose ratio and how the fermentation can vary that ratio. And that fructose can taste twice as sweet as glucose.
The one thing that caught my attention was that the conversion of grape sugars to alcohol can vary according to a number of factors, including "the architecture of the tank". Hmmm...that a new one to me and, as RandalGraham would say "counterintuitive".

It talks a lot about the concept of leaving RS in "dry" wines and how it can affect your sense of the wine.

Anyway, a rather interesting read by Kelli I thought.
Tom

[David M. Bueker]

A little too long and scientific for a football Sunday, especially while sick.

I’ll try to get back to it later.

The glucose/fructose sweetness thing is long known. I am surprised you were not aware of it.

I took the time to read the entire article - very interesting! However, she left out an important step. During fermentation the ratio of glucose to fructose changes, as yeast has a preference for glucose and will consume it first, leaving a higher percentage of fructose in the later stages of fermentation or in wines with residual sugar. Here is a link to a post of mine from a few years ago: http://forums.wineloverspage.com/viewtopic.php?f=3&t=49142&p=418652&hilit=fructose#p418652.

[David M. Bueker]

While not as direct as your statement Howie, she lays it out here:

Saccharomyces (whose very name translates to “sugar fungus”) preferentially consumes glucose; as a result, residual sugar is typically composed of 60 to 70% fructose, though this varies according to grape variety and yeast strain.

While not as direct as your statement Howie, she lays it out here:
Saccharomyces (whose very name translates to “sugar fungus”) preferentially consumes glucose; as a result, residual sugar is typically composed of 60 to 70% fructose, though this varies according to grape variety and yeast strain.

I was distracted by my cats when reading and missed that. Thanks for the catch, David.

[David M. Bueker]

Cats will do that. I have one in my lap right now.

The one thing that caught my attention was that the conversion of grape sugars to alcohol can vary according to a
number of factors, including "the architecture of the tank". Hmmm...

If you want the yeast and bacteria to conduct a "healthy" and "desirable" fermentation, not only do you want your
tank or vessel to contain a favorable medium, you want it designed to be suitable for the growth and survival of
the yeast and bacteria. In a sense you can think of it as a bioreactor.

Salute