Maths failure....

[Wynott]

Can anyone advise me on the following - don't think my record keeping was quite up to scratch, but I'm still very much a beginner!

I made some parsnip & ginger wine and noted the following:

O.G. 1.112 (with 2.5lbs sugar and a lot of parsnips and yes, I now know that's disastrously high) - it went down quite a bit (not recorded) so
Added another 8oz of syrup which made it 1.118 (overdid it a bit there...)
Went down to 0.986 so I added another 5oz. syrup
Went down to 0.994 so I added another 2.5oz syrup (see, I was being careful ;-))
Went down to 0.994 again, so I added another 2.5oz syrup (steady as you go....)
Eventually settled to 1.000 so I bottled it then.

It seems quite strong, but I can't work out the maths - e.g. how do I account for the extra water in the syrup?

Would welcome any educated guesses at the potential alchohol content!

 

[johncrobinson]

This ones a classic
I gave a very long winded reply on another thread some time ago about how to do it.
And I have forgotten the name of the thread.Sorry.
Unfortunately you need to prepare in advance if you are going to sugar feed.
You are quite correct the added water needs to be taken into account so you cant just use gravity drops as if you were using dry sugar.
The way round this is to use calibrated demijohns, Simply put its the total sugar in the total volume of water.
Its to late now for this wine to get a spot on figure,But i will compose a reply for you and either post it on this thread or pm you.I do have one important question did you use 300 gravity syrup.????
I need to know what strength the syrup was.
Off to bed now will look for your reply in the Morning

 

[johncrobinson]

I will try to work it out for you but i need the following
The formula for the syrup.
When you say you added "X" ounces of syrup,How did you measure this,Did you use scales to weigh the syrup or did you go by the fluid ounces on a measuring jug.

 

[Wynott]

Hi John

I used the syrup mix recommended by Berry - 1lb sugar to 1/2 pint of water. I then went by fluid ounces, by measuring jug for the 8oz. For the smaller quantities again referring to Berry 1tbsp = 1/2 fluid ounce.

A secondary question springs to mind, initially there will be some head space in the DJ (and some top-up to hand). The total of this would be 1 gallon, so adding syrup alters the volume - to say nothing of e.g. heavy sediment wines. What a lark this is...but an interesting one.

 

[johncrobinson]

In the meantime i will tell you how best to do this in future.
Warning: It involves LOTS of hydrometer readings (Drop method)
(Use a standard syrup,This is normally 300 gravity (1 pint of water to 1kg or 2.2lb sugar)

Prepare your must and take OG reading and note it.
When this has nearly fermented out take another gravity reading and note it.(A)
Add about 4 oz of syrup (its not critical how much) take another gravity reading and note it (b)
Allow this to ferment out And take another gravity reading and note it (c)

Carry on doing this ie taking Gravity readings before and after Every syrup addition and note them down

The next stage is to subtract the the before and after readings after each syrup addition to get the drop after each addition of syrup.

Here is a made up example:

Gravity reading (A) is 1.005 So its time to add a dose of syrup,With the added syrup the gravity is now 1.015
and noted we let this ferment out until a gravity reading of (say) 1.005 is reached that means a drop of 10 points Which again is noted.This is repeated for every syrup addition.

Lets say in this case we only add the one dose of syrup so as is standard we take the OG -FG which in this case is 1.080- 1.005 which gives a gravity drop of 75 which equates to an abv of 10.19%
We now add the gravity drop due to the addition of the syrup which is 10 So 75 +10=85 which equates to 11.54% abv,So the syrup has boosted the abv from 10.19% to 11.54%

Lets say we make 3 similar additions of syrup each with a gravity drop of 10 points.In this case we have
75+10+10+10=105 which then equates to 14.2%abv

I am getting the abv values from a table,But in case you don't have one,Its simple just divide the total gravity drop by 7.36 so 105/7.36 = 14.26%.

This is the gravity drop method,Heavy on the hydrometer.

 

[johncrobinson]

Well I call it the drop method,Its how I worked out how to do it
If you have any questions pm me.

In the meantime i will try for an approx figure for you existing wine.

 

[Wynott]

Thanks John. I have been working at calculating the wines with only one drop, by dividing by 7.36% and it gives me a good idea of strength, e.g. my carrot & wheat was strong, my rose petal less so.

It's useful to know just how much effort is involved in the feeding process. I have been avoiding backsweetening, which is how I got onto the feeding of wines.
There is a table in my copy of Berry, but your example above will be very helpful, I'll print it off.

 

[johncrobinson]

Well it ties in with your pm about the shelf life of wines,It is the best way of getting the alcohol content of wines up to the max (legally) achievable.

High alcohol wines properly kept are virtually immune to infection and deterioration.

There is a side affect though,That is working the yeast so hard tends to make it produce more esters and higher alcohols making the new high strength wine taste hot and harsh.These do mature out but since they are in a higher concentration than in table wines it takes a lot longer.
In cases where the yeast has had sub-optimal nutrition such as a traditional mead the same thing applies.