# Dextrose Aint Dextrose



## Dazza_devil (25/1/10)

G'day Brewers,
I asked my gf to pick me up 500g dextrose on her way through town and she showed up with a bag of Brigalow from Kmart.
Is it shite? Should I use it? There's no packing date on it.
Is there any difference with the quality of dextrose when comparing brands or is dextrose dextrose?
Cheers


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## glaab (25/1/10)

hasn't that brewboy turned up yet?, you aint puttin dex in it are you?


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## Dazza_devil (25/1/10)

Good to see you keepin track there glaab.
I've whimped out and gonna do another 3 extract brews while I rekindle my funds after the silly season.
Just a bitta dex to get my FG down a tad wont hurt.  
It'll be do or die after these.


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## manticle (25/1/10)

I can't imagine there'd be any discernible difference. I recently bought some Brigalow DME after I ran out and need to bump up a gravity after falling short.

I only used a couple of hundred grams but the rest has been used for starters. No problems with either.

Their hydrometers on the other hand................


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## Bribie G (25/1/10)

Brigalow are one of the oldest home brew supply companies in Australia and repack all sorts of stuff like gelatine finings, thermometers, etc and put their own logo on it. The dex would just be good old dex. Actually I often used dex instead of white sugar if I am putting, say 300g into a UK bitter because it's dead convenient - just pour it into the bottom of the fermenter, slosh in the wort from the cube and it's done. Lazy bugger me. 

If you want to be un-lazy you can do your own dex / fructose mix by inverting plain white sugar, with a quarter tsp of citric acid in water and simmer for 20 mins but I expect you would be aware of this. I often do this as well. I expect there must be some advantage in doing this as opposed to just chucking in the cane sugar, as the Poms have been doing it for around 150 years at their breweries and have quite a big sub-industry making various brewing sugars and syrups.


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## manticle (25/1/10)

BribieG said:


> Brigalow are one of the oldest home brew supply companies in Australia and repack all sorts of stuff like gelatine finings, thermometers, etc and put their own logo on it. The dex would just be good old dex. Actually I often used dex instead of white sugar if I am putting, say 300g into a UK bitter because it's dead convenient - just pour it into the bottom of the fermenter, slosh in the wort from the cube and it's done. Lazy bugger me.
> 
> If you want to be un-lazy you can do your own dex / fructose mix by inverting plain white sugar, with a quarter tsp of citric acid in water and simmer for 20 mins but I expect you would be aware of this. I often do this as well. I expect there must be some advantage in doing this as opposed to just chucking in the cane sugar, as the Poms have been doing it for around 150 years at their breweries and have quite a big sub-industry making various brewing sugars and syrups.



My understanding of the supposed advantage is that it makes the sugar easier for the yeast to digest as during metabolism they have to invert sucrose themselves anyway. They produce an enzyme called invertase which is supposedly a cause of green apple/acetylaldehyde.

I have no idea as I've heard many brewers claim plain table sugar is fine (I mean brewers who seem to know what's going on). I invert sugar for my Belgians but that's mainly because I reduce it down to a thick, dark syrup


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## Bribie G (25/1/10)

Yes the enzyme is invertase and there's plenty of it in yeast, but I don't know if it produces an off flavour... in the 19th century they developed a method of inverting cane sugar (The Tompson's Yeast Process) that consisted of pitching live yeast into a very hot solution of cane sugar at 55 degrees C, and the invertase in the yeast would invert the sugar before the yeast actually karked it, then the whole slurry would be poured into the kettle to be boiled. Presumably the yeast would be curdled and drop out with the rest of the trub, or at least act as yeast nutrient. I'll try it myself with some left over yeast cake, but not at the moment (doing some comp ales  )

It is these heroic efforts by Victorian brewers to invert sugar that makes me think there must be some some actual industry-recognised benefit from doing so.


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## manticle (25/1/10)

As far as I know breweries around the world use both invert and sucrose without running into green apples so I'm not sure. I reckon it's a bit like the white-talied spider myself.


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## Bribie G (25/1/10)

Or hot side aeration :lol:  B)


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## Nick JD (25/1/10)

Brigalow's dextrose IIRC has on the packet, "100% Glucose Monohydrate". D-glucose.

I just looked this up because I've always wondered what the hell dextrose and glucose had to do with each other and...

Dextrose is an isomer (same shit, different shape) of glucose. It is *dextrorotatory *glucose (as opposed to being levorotary glucose, which can't be eaten). Must be something to do with being right-handed.

It looks like this:






Sucrose looks like this:






Which, as you can see is basically a glucose and a fructose stuck together. Invertase must pop that red oxygen between the fructose and the glucose.

There's bugger all difference between fructose and glucose.


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## Dazza_devil (25/1/10)

All very interesting.

I found this chemical formula for Glucose Monohydrate, C6H12O6.H2O

This Chemical formula for glucose, C6H12O6

Not sure what the water molecule is doing attached in that example. I did 2 years of Chemistry at college but it's all too long ago and over my head at the moment.


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## Nick JD (28/1/10)

Boagsy said:


> All very interesting.
> 
> I found this chemical formula for Glucose Monohydrate, C6H12O6.H2O
> 
> ...



Just a guess, but it's probably expensive to take the water out and keep it out.


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## Spartan 117 (28/1/10)

Boagsy said:


> All very interesting.
> 
> I found this chemical formula for Glucose Monohydrate, C6H12O6.H2O
> 
> ...



I think, not sure, but crystalline structures of sugars exist as rings, however in there hydrated form the ring breaks absorbing one molecule of water, one of the reasons sugars can be so soluble in water, hope this helps 

Aaron


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