OG / SG Calculations
 

Hello.

I hope my question is a simple one. Basically I am making a wine at the moment and due to a schoolboy error I made just
over 28 litres (just over 6 UK Gallons) rather than 23 litres. That meant that I had to hold back 2.5 litres of water
(from a final 28 gallon must) until I removed the bag of fruit. The original recipe is all in the correct ratios.

My OG was about 1.124. Is there a simple way of calculating what the Specific Gravity at the start would have been
including the extra 2.5 litres? I imagine it would be as simple as:

((Original SG - 1) * (original volume of liquid/final volume of liquid))+1

(0.124 * (25.5/28))+1 = 1.113

Is that right or is there an obvious anomaly there?

Many thanks, Jim

OG / SG Calculations
 

Jim -

I think your calculations are correct, or at least, near enough
for your purposes. At 1.124 you have high enough S.G. that you might
have difficulty getting fermentation started. Assuming that wasn't a
problem, I think you can treat the 28 gallon batch (after you add the
last 2.5 liters of water) as if it started at 1.113.

Doug

OG / SG Calculations
 

The confirmation is very much appreciated here Doug. On the recommendation of a friend I used gervin no.3 (champagne
style) rather than no.2 (montrachet red style) yeast and it has coped admirably. I am glad I trusted his wisdom in the
absence of my own!

I will proceed with that estimate in mind :D

Jim

"Doug" > wrote in message oups.com...
> Jim -
>
> I think your calculations are correct, or at least, near enough
> for your purposes. At 1.124 you have high enough S.G. that you might
> have difficulty getting fermentation started. Assuming that wasn't a
> problem, I think you can treat the 28 gallon batch (after you add the
> last 2.5 liters of water) as if it started at 1.113.
>
> Doug
>

OG / SG Calculations
 

On Jan 29, 12:42 pm, "jim" > wrote:
> Hello.
>
> I hope my question is a simple one. Basically I am making a wine at the moment and due to a schoolboy error I made just
> over 28 litres (just over 6 UK Gallons) rather than 23 litres. That meant that I had to hold back 2.5 litres of water
> (from a final 28 gallon must) until I removed the bag of fruit. The original recipe is all in the correct ratios.
>
> My OG was about 1.124. Is there a simple way of calculating what the Specific Gravity at the start would have been
> including the extra 2.5 litres? I imagine it would be as simple as:
>
> ((Original SG - 1) * (original volume of liquid/final volume of liquid))+1
>
> (0.124 * (25.5/28))+1 = 1.113
>
> Is that right or is there an obvious anomaly there?
>
> Many thanks, Jim

Jim,
The difference between 28 litres and 25.5 litres is 2.5 of water.
But, let say that instead of water, with an SG of 1.000, you had to
use another must with an SG of, let say 1.080. What then would have
been your solution?

Guy

Guy

OG / SG Calculations
 

Wow, I don't know, it took me while to figure out that I needed to ignore the 1.000 in my calculations below and add it
back at the end ;) I just juggle numbers till it looks right!

The best algorythm I could come up with was this, I don't know if it is right but it looks likely?

(((original SG-1) * number of litres at SG)+((added SG-1) * number of litres at SG)) / total litres in fermenter at end)
+ 1

so in the original example modified to use an added solution at an SG of 1.080:

((3.162 +0.2 )/28)+1
FINAL SG 1.120

Does that sound about right to you? It looks like it might be to me.

An alternative which may only give different results because of liberties I took with rounding.

((original SG-1) * (number of litres at this SG/total number of final litres) + ((diluting solution SG-1) *(number of
litres at this SG/total number of final litres) )+1 = estimated starting diluted SG

so...

0.124 * (25.5/28) + 0.080 * (2.5/28) + 1
= 0.112 + 0.007 + 1
FINAL SG 1.119

My head is too fuzzy after thinking all that to perceive if it is really logical or different at all! They could both
be wrong ha ha here in England it is 3.04 am so forgive my waffle !

Jim


"guy" > wrote in message ups.com...
>
>
> On Jan 29, 12:42 pm, "jim" > wrote:
>> Hello.
>>
>> I hope my question is a simple one. Basically I am making a wine at the moment and due to a schoolboy error I made
>> just
>> over 28 litres (just over 6 UK Gallons) rather than 23 litres. That meant that I had to hold back 2.5 litres of water
>> (from a final 28 gallon must) until I removed the bag of fruit. The original recipe is all in the correct ratios.
>>
>> My OG was about 1.124. Is there a simple way of calculating what the Specific Gravity at the start would have been
>> including the extra 2.5 litres? I imagine it would be as simple as:
>>
>> ((Original SG - 1) * (original volume of liquid/final volume of liquid))+1
>>
>> (0.124 * (25.5/28))+1 = 1.113
>>
>> Is that right or is there an obvious anomaly there?
>>
>> Many thanks, Jim
>
> Jim,
> The difference between 28 litres and 25.5 litres is 2.5 of water.
> But, let say that instead of water, with an SG of 1.000, you had to
> use another must with an SG of, let say 1.080. What then would have
> been your solution?
>
> Guy
>
> Guy
>

OG / SG Calculations
 

Sorry, I horribly misused conventions above. By FINAL SG in my results I meant predicted 'diluted OG'.

Jim


"jim" > wrote in message ...
> Wow, I don't know, it took me while to figure out that I needed to ignore the 1.000 in my calculations below and add
> it back at the end ;) I just juggle numbers till it looks right!
>
> The best algorythm I could come up with was this, I don't know if it is right but it looks likely?
>
> (((original SG-1) * number of litres at SG)+((added SG-1) * number of litres at SG)) / total litres in fermenter at
> end) + 1
>
> so in the original example modified to use an added solution at an SG of 1.080:
>
> ((3.162 +0.2 )/28)+1
> FINAL SG 1.120
>
> Does that sound about right to you? It looks like it might be to me.
>
> An alternative which may only give different results because of liberties I took with rounding.
>
> ((original SG-1) * (number of litres at this SG/total number of final litres) + ((diluting solution SG-1) *(number of
> litres at this SG/total number of final litres) )+1 = estimated starting diluted SG
>
> so...
>
> 0.124 * (25.5/28) + 0.080 * (2.5/28) + 1
> = 0.112 + 0.007 + 1
> FINAL SG 1.119
>
> My head is too fuzzy after thinking all that to perceive if it is really logical or different at all! They could both
> be wrong ha ha here in England it is 3.04 am so forgive my waffle !
>
> Jim
>
>
> "guy" > wrote in message ups.com...
>>
>>
>> On Jan 29, 12:42 pm, "jim" > wrote:
>>> Hello.
>>>
>>> I hope my question is a simple one. Basically I am making a wine at the moment and due to a schoolboy error I made
>>> just
>>> over 28 litres (just over 6 UK Gallons) rather than 23 litres. That meant that I had to hold back 2.5 litres of
>>> water
>>> (from a final 28 gallon must) until I removed the bag of fruit. The original recipe is all in the correct ratios.
>>>
>>> My OG was about 1.124. Is there a simple way of calculating what the Specific Gravity at the start would have been
>>> including the extra 2.5 litres? I imagine it would be as simple as:
>>>
>>> ((Original SG - 1) * (original volume of liquid/final volume of liquid))+1
>>>
>>> (0.124 * (25.5/28))+1 = 1.113
>>>
>>> Is that right or is there an obvious anomaly there?
>>>
>>> Many thanks, Jim
>>
>> Jim,
>> The difference between 28 litres and 25.5 litres is 2.5 of water.
>> But, let say that instead of water, with an SG of 1.000, you had to
>> use another must with an SG of, let say 1.080. What then would have
>> been your solution?
>>
>> Guy
>>
>> Guy
>>
>
>

OG / SG Calculations
 

Wow! I may be the only one who thinks this, but winemaking is the
farthest refuge I could find from complex math!

Well done Jim~!

OG / SG Calculations
 

> I hope my question is a simple one. ...
> ... 28 litres (just over 6 UK Gallons) rather than 23 litres.
> That meant that I had to hold back 2.5 litres of water
> (from a final 28 gallon must) until I removed the bag of fruit. ...
>
> My OG was about 1.124. Is there a simple way of calculating what
> the Specific Gravity at the start would have been
> including the extra 2.5 litres? I imagine it would be as simple as:
>
> ((Original SG - 1) * (original volume of liquid/final volume of liquid))+1
>
> (0.124 * (25.5/28))+1 = 1.113
>
> Is that right or is there an obvious anomaly there?

With beer brewing, you get to play with this sort of stuff a lot if you
want to figure your efficiencies and such. The easiest way is to deal
with "sugar points." With beer, we usually use gallons... but it should
work using liters. You drop off the "1.000" part, so 1.124 becomes 124
points:
124 * 25.5 = 3162 total sugar points (liters).
Now you know how many sugar points you have, you can divide by any number
of liters to see what the gravity would be then:
3162 / 23 = 137.5
or in your case:
3162 / 28 = 112.9
Then you just put the 1.000 back onto it: 1.1129

Or you can divide by the gravity to see what the volume (liters) would be.
Dealing with the points this way makes it easy to, for example, figure
how much water to add to reach a desired OG.
You have 1.124 @ 25.5 liters and want 1.100:
124 * 25.5 = 3162 total points
3162 / 100 = 31.62 total liters
31.62 - 25.5 = 6.12 liters to add to get 1.100.

So your math was right, but done differently from how I would have done
it!

Derric

OG / SG Calculations
 

Well, I thought I posted a reply but it's not showing up, so here goes
again - these calculations can be handled well by Pearson square. Jack
Keller has an online version at

http://winemaking.jackkeller.net/blending.asp

Use the one in section Solving Adjusted Alcohol of a Blend - it works
for any substance where you're mixing 2 different quantities and
concentrations, not just alcohol.

Pp


On Jan 29, 7:04 pm, "jim" > wrote:
> Wow, I don't know, it took me while to figure out that I needed to ignore the 1.000 in my calculations below and add it
> back at the end ;) I just juggle numbers till it looks right!
>
> The best algorythm I could come up with was this, I don't know if it is right but it looks likely?
>
> (((original SG-1) * number of litres at SG)+((added SG-1) * number of litres at SG)) / total litres in fermenter at end)
> + 1
>
> so in the original example modified to use an added solution at an SG of 1.080:
>
> ((3.162 +0.2 )/28)+1
> FINAL SG 1.120
>
> Does that sound about right to you? It looks like it might be to me.
>
> An alternative which may only give different results because of liberties I took with rounding.
>
> ((original SG-1) * (number of litres at this SG/total number of final litres) + ((diluting solution SG-1) *(number of
> litres at this SG/total number of final litres) )+1 = estimated starting diluted SG
>
> so...
>
> 0.124 * (25.5/28) + 0.080 * (2.5/28) + 1
> = 0.112 + 0.007 + 1
> FINAL SG 1.119
>
> My head is too fuzzy after thinking all that to perceive if it is really logical or different at all! They could both
> be wrong ha ha here in England it is 3.04 am so forgive my waffle !
>
> Jim
>
>
>
> "guy" > wrote in oglegroups.com...
>
> > On Jan 29, 12:42 pm, "jim" > wrote:
> >> Hello.
>
> >> I hope my question is a simple one. Basically I am making a wine at the moment and due to a schoolboy error I made
> >> just
> >> over 28 litres (just over 6 UK Gallons) rather than 23 litres. That meant that I had to hold back 2.5 litres of water
> >> (from a final 28 gallon must) until I removed the bag of fruit. The original recipe is all in the correct ratios.
>
> >> My OG was about 1.124. Is there a simple way of calculating what the Specific Gravity at the start would have been
> >> including the extra 2.5 litres? I imagine it would be as simple as:
>
> >> ((Original SG - 1) * (original volume of liquid/final volume of liquid))+1
>
> >> (0.124 * (25.5/28))+1 = 1.113
>
> >> Is that right or is there an obvious anomaly there?
>
> >> Many thanks, Jim
>
> > Jim,
> > The difference between 28 litres and 25.5 litres is 2.5 of water.
> > But, let say that instead of water, with an SG of 1.000, you had to
> > use another must with an SG of, let say 1.080. What then would have
> > been your solution?
>
> > Guy
>
> > Guy- Hide quoted text -
>
> - Show quoted text -

OG / SG Calculations
 

On Jan 29, 10:04 pm, "jim" > wrote:

> (((original SG-1) * number of litres at SG)+((added SG-1) * number of litres at SG)) / total litres in fermenter at end)
> + 1
>
> so in the original example modified to use an added solution at an SG of 1.080:
>
> ((3.162 +0.2 )/28)+1
> FINAL SG 1.120
>
> Does that sound about right to you? It looks like it might be to me.

That is right by me. A slight modification is to use the original SG
without subtracting and then adding 1. Also, I always use the quantity
first, so:

25.5 L (1.124) + 2.5 L (1.080) / 28 L = 31,362 L / 28 L = 1.120

That was a good subject Jim

Guy