# Dextrose vs. sucrose



## Bartman (Dec 31, 2010)

Is there a difference between using dextrose or sucrose in raising the ABV of a wine kit, like an Orchard Breezin Green Apple Riesling? George/FVW sells corn sugar (dextrose) and I have added that for chaptalization of a port kit, but have added sucrose (table sugar) to a couple kits to raise the ABV a small degree. I have also added sweetened flavorings (i.e., peach nectar) to kits, which have corn syrup and sugar in them.

Bottom line, I can't taste a difference between the different forms of sugar once it is fermented. Wikipedia is of limited help, mentioning that dextrose is also known as grape sugar because it is the form of sugar that is most common in grapes and ferments into the alcohol in wine, leaving some non-fermentable residual sugars behind (even in "dry" wines). Sucrose is apparently part fructose and part glucose. Is dextrose/corn sugar which George sells a "better" sugar to use in winemaking than table sugar from Wal-mart in some way? Does it ferment more quickly/easily?

If it makes no difference in the final product, why do some kits call for dextrose instead of table sugar?

I have cut-and-pasted a portion of the Wikipedia entry for your edification, if 
interested...

<h2>Glucose</span></h2>


Glucose, along with fructose, is one of the primary sugars found in 
wine grapes. In wine, glucose taste less sweet than fructose. It is a 
six-carbon atom sugar derived from the breakdown of sucrose. At the 
beginning of the ripening stage
there is usually more glucose than fructose present in the grape (as 
much as five times more) but the rapid development of fructose evens 
shifts the ratio out to where at harvest there is generally equal amounts. Grapes that are over ripe, such as some late harvest wines,
may have more fructose than glucose. During fermentation, yeast break 
down and convert glucose first. The linking of glucose molecules with aglycone, in a process that creates glycosides, also plays a role in the resulting flavor of the wine due to their relation and interactions with phenolic compounds like anthocyanins and terpenoids.<sup id="cite_ref-Oxford_pg_317_1-0" ="reference">[</span>2]</span></sup>
<h2></span>Fructose</span>

</h2>
<div ="thumb tright"><div ="thumbinner" style="width: 202px;">http://en.wikipedia.org/wiki/File:Sandeman_Port_2.jpg
<div ="thumbcaption">

In wines like Port,
the addition of neutral grape spirits stuns the yeast and halts 
fermentation, leaving a wine with a higher proportion of fructose sugars
and creating a sweet wine.




Fructose, along with glucose, is one of the principle sugars involved
in the creation of wine. At time of harvest, there is usually an equal 
amount of glucose and fructose molecules in the grape; however, as the 
grape over ripens
the level of fructose will become higher. In wine, fructose can taste 
nearly twice as sweet as glucose and is a key component in the creation 
of sweet dessert wines.
During fermentation, glucose is consumed first by the yeast and 
converted into alcohol. A winemaker that chooses to halt fermentation 
(either by temperature control or the addition of brandy spirits in the process of fortification) will be left with a wine that is high in fructose and notable residual sugars. The technique of _süssreserve_, where unfermented grape must
is added after the wine's fermentation is complete, this will result in
a wine that tastes less sweet than a wine whose fermentation was 
halted. This is because the unfermented grape must will still have 
roughly equal parts of fructose and the less sweet tasting glucose. 
Similarly, the process of chaptalization
where sucrose (which is one part glucose and one part fructose) is 
added will usually not increase the sweetness level of the wine.<sup id="cite_ref-Oxford_pg_290_2-0" ="reference"></span></sup>


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## AlFulchino (Dec 31, 2010)

great question...looking forward to seeing what Mike has to say on this

sounds like an opportunity to do a side by side w a couple of 1-2 gallon carboys


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## Dean (Dec 31, 2010)

I can't say I'm an expert on this, but it was explained this way to me from Tim Vandergrift. Dextrose, a pure simple sugar can be eaten by the yeast immediately. Sucrose, is a double sugar, containing 1 glucose and 1 fructose. The yeast have to break that bond to eat them. 

When fermentation is just getting started, it's easy for a large yeast population to break down sucrose. As fermention gets near the end of the tolerance for yeast, breaking down sucrose is sometimes too much for them, so the use of a simple sugar like dextrose is used instead.

Instead of using dextrose, you can take sucrose, and make liquid invert, which breaks that bond for you. All you need is the required amount of table sugar, enough water to dissolve it all, and a few teaspoons of lemon juice. The acid in the lemon juice, under simmering temperatures for 20 minutes will create free glucose and free fructose. Then you can chaptalize with that, and have the same effect as dextrose.

It doesn't make any difference in wine that I've found either, however, some beer makers have used table sugar as priming sugar and claim that there is a bit of a harsh aftertaste when using it.


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## Bartman (Jan 3, 2011)

So, Dean, are you suggesting that if you intend to use sucrose in the course of upping the ABV from the start, you should add all the table sugar up front? Some references I have seen recommend adding it gradually, keeping the S.G. around 1.040 as the primary fermentation proceeds.

Conversely, you seem to be suggesting that dextrose can be added at any time prior to fermentation ending, or even to restart fermentation, Yes?


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## Dean (Jan 3, 2011)

Yes, that was how it was explained to me. Sucrose all up front, and then if you have to add later either liquid invert (broken sucrose) or dextrose so the yeast don't have to work hard. It can restart fermentation provided that the yeast are not at the end of their tolerance.


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