Dextrose question

[C5babe]

I’m starting a white grape/peach wine and have been told by a friend to try dextrose instead of sugar. The recipe calls for .75 cups of sugar, but is dextrose the same measure? How do I convert sugar to dextrose?

 

[GirthySquirt]

I’m starting a white grape/peach wine and have been told by a friend to try dextrose instead of sugar. The recipe calls for .75 cups of sugar, but is dextrose the same measure? How do I convert sugar to dextrose?

Hi C5babe,

Dextrose is another name for glucose, which is the simplest "sugar" molecule - see the wiki: Glucose - Wikipedia.

Table sugar, otherwise known granulated sugar, is sucrose (a combination molecule that links glucose with another simple sugar, fructose).

Yeast can easily break sucrose into it's sub-constituent molecular components (glucose + fructose), but it could be beneficial in some scenarios to start entirely with glucose, which should theoretically be the "easiest" sugar for yeast to metabolize and use for energy, depending on what exactly you are doing. I've never used exclusively one sugar, but it looks online like there are lots of dextrose/glucose powders and syrups you can by that exclusively contain the one simple sugar.

It may be worth mentioning the fermenting with just the simplest sugars will yield an incredibly "dry" alcohol with hardly any "residual sweetness" left, since the yeast can ferment these purified adjuncts to ethanol completely. Take honey for example, which consists of about 95% simple sugars that yeast can readily ferment. If you ferment honey with yeast you end up fermenting about 95% of the way down from your original gravity since so much of the added honey is fermentable. With purified glucose syrup you may similarly be able to get an even more dry final product where almost all the sugar is consumed, which may or may not be your goal.

It sounds like you are just trying to bump up the final ABV up in your brew by adding dextrose in addition to your fruit for the yeast to convert, in which case adding dextrose would do exactly that as long as the yeast you use can handle the amount of alcohol you are planning to have.

I should also mention that adding regular granulated sugar should do the exact same thing, since yeast should be able to consume sucrose just as readily - I am not 100% sure about this though and would be interested what others think regarding this, does anyone have experience with adding regular granulated sugar compared to adding glucose/dextrose syrup for fermentation? I would think that for this application the yeast will be able to ferment glucose or sucrose the same way, and I would just add the regular sugar just as the recipe calls for.

 

[C5babe]

Thank you for the info. I’m just learning the art of wine making, and quite honestly, I have very little idea of what I’m doing. I’ve made one or three cranberry wines that I like, but made a peach abomination that was just…..foul. Oh well, back to the drawing board!

 

[doug293cz]

If you are worried about precise equivalents for different sugars, you need to be adding by weight, not volume. There are lots of low cost digital scales available that will give you much more accurate results than volume measurements of granulated sugars.

As far as sucrose (table sugar) vs. dextrose/glucose, most of the dextrose available is dextrose mono-hydrate, since pure dextrose readily picks up water and clumps up. You need 10% more dextrose vs. sucrose (by weight) to get the same amount of potential alcohol.

If you bring syrups into the mix, you have to know the water content of the syrup in order to figure out the equivalence to solid forms of sugar.

Brew on

 

[hotbeer]

If you make it the way the recipe suggests then you'll have something to compare with a batch made with the suggestion of your friend. Otherwise you won't really know if it is actually better to you. And unless you are trying to impress judges, then what you like is all that matters.