Dextrose vs White Sugar

[BrisBrew]

Im wondering what the diference is between white sugar and dextrose in a ferment.

im doing an experiment with a fruit juice and i added a few grams of white sugar to bump the ABV up but im wondering if dextrose is better being i have no idea which is better for flavour or to reduce bad of flavours.

I tried googling but couldnt find a home brew reason why, just a lot about their chemical states and suff which didnt help me to find out whats best for flavour.

Should i use dextrose instead of white sugar? and if so why, will it taste better/worse?

Cheers

 

[MHB]

Hard to answer definitively without a lot of pretty complex looking at chemical states.
Short answer is that most fruit contains Sucrose so adding a little more wont have a big impact on the flavour.

Where the difference appears to come from is the way yeast metabolises sugars, Glucose (dextrose), Fructose and Maltose are taken up by the yeast and fully metabolised inside the cell. Yeast cant import Sucrose, so it make an enzyme called Invertase secretes that into solution, the enzyme reduces the Sucrose into Glucose and Fructose which the cell then takes up.
The enzyme stays in the ferment and persists all the way to the glass. The exact effects on flavour are really hard to pin down but it appears that large amounts of invertase in solution will affect the flavour. The other problem being people - bloody individuals, they don't all taste things the same, personal preference will matter.
Mark

 

[hoppy2B]

A good point about personal preferences by MHB. Different yeast strains might give different results too. So the short answer is that it is something that one needs to experiment with.

I've read that sugar will give an apple cider sort of flavour. I have also read that dextrose will increase ester production. Dextrose is meant to be better for yeast health. As mentioned above, it is easier for yeast to digest the single molecule of dextrose compared to the double molecule of sucrose.

Last of all, dextrose will yield a slightly lower abv and carbonation lever (when used for bottle priming) compared to sucrose.

So maybe use sucrose when fermenting apple cider and dextrose when fermenting your banana mango smoothy.

 

[BrisBrew]

Cheers guys. all i have done so far is got an apple/blackcurrant juice (2L golden circle bottle) and added 40-50 grams of sugar and a high tollerent ABV white dry wine yeast. by my calcs it might be somewhere a 6.5%abv when done but i never checked SG, just read 8.5 grams per 100ml juice on the bottle and added what i wanted on top, about 45 grams.

It is in the bottle it came in with an airlock in the lid but ill start doing small experiments in my 5L demi after this one. just need a bung for the demi and airock.

I will try diffenent things and see how i go but as for sugar I think ill stick to sucrose for now. will be fun trying small experiments as well as my normal beer ferments

cheers

 

[MHB]

Wine and Cider yeasts are breed to eat Sucrose, Beer yeast really isn't, so its a pretty good rule of thumb to stick with what the yeast is best at Sucrose for Wine/Cider. Dextrose, Maltose (Wort, DME, LME) for beer yeast.
Will at least have less unexpected affects on flavour, a touch of nutrient is a very good idea.
Mark

 

[hoppy2B]

just need a bung for the demi and airock.

Some glad wrap or foil over the top would suffice.

 

[pcmfisher]

Hard to answer definitively without a lot of pretty complex looking at chemical states.
Short answer is that most fruit contains Sucrose so adding a little more wont have a big impact on the flavour.

Where the difference appears to come from is the way yeast metabolises sugars, Glucose (dextrose), Fructose and Maltose are taken up by the yeast and fully metabolised inside the cell. Yeast cant import Sucrose, so it make an enzyme called Invertase secretes that into solution, the enzyme reduces the Sucrose into Glucose and Fructose which the cell then takes up.
The enzyme stays in the ferment and persists all the way to the glass. The exact effects on flavour are really hard to pin down but it appears that large amounts of invertase in solution will affect the flavour. The other problem being people - bloody individuals, they don't all taste things the same, personal preference will matter.
Mark

MHB, After the invertase reduces the Sucrose does the yeast ferment the Glucose and Fructose at the same time or does it chomp through one and then move onto the other?

 

[MHB]

I believe all the simple sugars are treated equally, they are chemically the same just arranged differently (isomers). Yeast will preferentially take up single sugars, then twin sugars (Mono and Disaccharides) then some trisaccharide's...
Mark