Difference between brix and SG in wine measurement

Help Support The HomeBrew Forum:

andrew_ysk

Active Member
Joined
Aug 15, 2020
Messages
78
Reaction score
2
I am taking measuring with both brix and sg.
So far what i read was, refractormeter measures sugar, but it reading can be affected by alcohol, hence it is not advicable to use it to measure remaining sugar (in brix) in fermented "wine".. because there is alcohol + sugar in it .
But then, come to think of it.
When we measure sugar with hydrometer in a liquid that contain only sugar, it works fine. But after the "wine" fermented ; alcohol is present along with remaining sugar.. hence isn't it having the same issue as brix meter ?
**because alcohol is lighter than water (SG=1), hence with sugar + alcohol in the liquid, we won't know how much is sugar and how much is alcohol in the "wine".
Since hydrometer is having exactly the same issue as with brix meter, why then, brewers keep insisting to take measurement with hydrometer instead of simpler refractormeter ?
Am i missing something ?
 

johncrobinson

Landlord.
Joined
Sep 13, 2019
Messages
2,098
Reaction score
1,058
Location
Highlands
A Brix reading with a refractometer can be usefull at the start of fermentation.

Yes both are affected by the alcohol,However the gravity drop indicated by a hydrometer is a good indication of the progress of fermentation.
Not all sugars are fermentable SG-FG gives a pretty good aproximation of what is going on.

BTW I dont know anyone here in UK that uses "brix" Its all specific gravity this side of the pond, 😁
 

Stevieboy

Landlord.
Joined
Aug 9, 2019
Messages
590
Reaction score
414
Location
Wimborne, Dorset
The way I see it is that commercial wine makers use Refractometers in the field to determine whether to harvest or not, because they depend solely on the juice of the harvest for the final wine, and are rarely allowed to chaptalise.

In homebrewing, you need make up your must to the desired SG, normally by adding sugar, because there isn't enough in the grape juice, because you are normally using desert grapes/supermarket juice cartons.

Even if you do grow wine grapes in the UK, it is always a knife edge affair - poor light levels, short sun-days high humidity in autumn, etc make it very hard to ripen wine grapes. It's common for commercial wineries in the UK to chaptalise, and why many of our wines are described as "fresh" - which a euphamism for "bloody hell that's acidic and dry"

This is why the Hydrometer is king in homebrewing.
 

andrew_ysk

Active Member
Joined
Aug 15, 2020
Messages
78
Reaction score
2
A Brix reading with a refractometer can be usefull at the start of fermentation.

Yes both are affected by the alcohol,However the gravity drop indicated by a hydrometer is a good indication of the progress of fermentation.
Not all sugars are fermentable SG-FG gives a pretty good aproximation of what is going on.

BTW I dont know anyone here in UK that uses "brix" Its all specific gravity this side of the pond, 😁
I didn't get the answer i desired from this thread so far. Maybe it is me who overlooked on some content here.

Yes, hydrometer also affected by alcohol, but since you said "the drop indicated by a hydrometer is a good indication of the progress of fermentation", then let me ask again:
Why just not use refractormeter ? "the drop in brix reading also a good indication of the progress of fermentation" . . then why not use refractormeter instead of big bulk hydrometer (that waste a lot of juice [especially for small home brewer] ) ?
 

Stevieboy

Landlord.
Joined
Aug 9, 2019
Messages
590
Reaction score
414
Location
Wimborne, Dorset
Having done some research, they both seem to achieve the same thing, and they both have pros and cons, but as long you follow the instructions and make adjustments for temperature etc, then you'll be fine.

As for the loss of liquid - if 100ml is a problem, then you really are brewing on a small scale....
 

Hopsteep

Flat out like a lizard drinking
Supporting Member
Joined
May 19, 2017
Messages
1,351
Reaction score
1,238
Location
Essex
The way I see it is that commercial wine makers use Refractometers in the field to determine whether to harvest or not, because they depend solely on the juice of the harvest for the final wine, and are rarely allowed to chaptalise.

In homebrewing, you need make up your must to the desired SG, normally by adding sugar, because there isn't enough in the grape juice, because you are normally using desert grapes/supermarket juice cartons.

Even if you do grow wine grapes in the UK, it is always a knife edge affair - poor light levels, short sun-days high humidity in autumn, etc make it very hard to ripen wine grapes. It's common for commercial wineries in the UK to chaptalise, and why many of our wines are described as "fresh" - which a euphamism for "bloody hell that's acidic and dry"

This is why the Hydrometer is king in homebrewing.
Spot on this 👍

The exception is Essex in the Crouch Valley where ripeness regularly hits the 12.5 to 13.5% abv mark. 90% of uk wineries not in Essex or the south east buy their grapes from Essex growers. They’re not obliged to state that on the bottle as there are no laws like in France, which I think is a bit naughty! 🍷

I’m in Essex and planted Pinot Noir in the garden a couple of years ago. Next year will be my first ‘harvest’ but I did allow one vine to fruit. I got just over a kilo of fruit off it this year so it’s been crushed and de-stemmed and put into a demijohn for a bit of fun! OG 1.083 so looking at about 11% despite the horrible summer 🤞
 

johncrobinson

Landlord.
Joined
Sep 13, 2019
Messages
2,098
Reaction score
1,058
Location
Highlands
What do you desire andrew. ??????

If you are a commercial brewer then you will have to abide by the local regulations,I can have no influece over that.
If you are trying to set up a winery on the continent then good luck..
Bad Summers are one of those things most wine producers factor in, mixing old and new wines to get a saleable product.
There is no need to be worried about been a comerciall producer on this forum.
Most members accept allsorts of opinion.
 

Tavi-brewer

Active Member
Joined
Jul 24, 2021
Messages
63
Reaction score
46
Location
Tavistock
I spent some time with a winemaker and my impression was that they use a refractometer whilst walking around the vineyard to check on the sugar content of the grapes in realtime, as it were.
As we know they need to be picked at the peak of ripeness and sugar content and hours can be pivotal to success.
With a refractometer you can pick a grape, squeeze the juice on it and get an instant value. So it's convenience as I see it. Can't see a vintner making a must in a field using precious grapes with sufficient volume to take a specific gravity.
At the end of fermentation then anything goes as there are plenty of conversion sets to finalise the ABV.
Just another thought ;)
T
 

andrew_ysk

Active Member
Joined
Aug 15, 2020
Messages
78
Reaction score
2
Having done some research, they both seem to achieve the same thing, and they both have pros and cons, but as long you follow the instructions and make adjustments for temperature etc, then you'll be fine.

As for the loss of liquid - if 100ml is a problem, then you really are brewing on a small scale....
The issue is , i was making grape wine in 4 liter jars... lol so, at the end of the whole thing, i got like 2.5 - 3.5liter (max) of wine only.. so... lol
 

andrew_ysk

Active Member
Joined
Aug 15, 2020
Messages
78
Reaction score
2
mers are one of those th
I spent some time with a winemaker and my impression was that they use a refractometer whilst walking around the vineyard to check on the sugar content of the grapes in realtime, as it were.
As we know they need to be picked at the peak of ripeness and sugar content and hours can be pivotal to success.
With a refractometer you can pick a grape, squeeze the juice on it and get an instant value. So it's convenience as I see it. Can't see a vintner making a must in a field using precious grapes with sufficient volume to take a specific gravity.
At the end of fermentation then anything goes as there are plenty of conversion sets to finalise the ABV.
So, it is perfectly fine to measure grape juice and wine with refractormeter ? I have Never heard any recommendation of making wine with brix meter... That's why i want to know why ?
I heard everybody said refractormeter got affected by alcohol which render it inaccurate.. Then again, (as i have mentioned) hydrometer also affected by alcohol (to to alcohol weight different than water).
I just want an satisfactory answer only.

** i have both digital refractormeter and hydrometer, hence if it is perfectly fine to measure ABV using refractormeter, then it is much easier and faster for me to use that than hydrometer.. But if it is because of some other reason that i may have missed out.. than i want to know what is it.. **
 

Latest posts

Top