specific gravity problem

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Sep 30, 2009
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My first try is a Concord grape wine. One week ago I followed a recipe for Concord grape wine. After a week it seems to be progressing but I learned that I should have added more sugar. The starting SG was only about 1.050. I think it should have been around 1.1. After a week it's down to 1.2. Is it too late to get it up to 1.1? What should it be now? Thanks for any help.
I have no experience with Concord so I do not know if such a high gravity-gaining high alcohol is ok for this wine.

But you can add sugar at any stage during the fermentation process.
So as long as it is bubbling it is ok to add sugar.

I would not overdo it as a high alcohol wine might taste like rocket fuel. However like stated before I have no experience with concord grapes.

Broy any sugar you add should be dissolved in warm water, or maybe a little bit of your must. Don't get it too hot, just warm enough to dissolve the sugar. And you don't need alot of liquid to dissolve it, again, just enough.
specific gravity

Thanks. Let me clarify. The recipe I followed says that the SG should be at least 1.095 in the beginning and that it will drop to 1.030 after 5-6 days. So if it was only at 1.050 to start and it's 1.02 now after 6 days, should I try to bring it up to 1.095 now or to 1.030 or what?
I would not take it to 1.095 now. it will be sweet rocket fuel. I would guess at 2 cups or sugar should be fine
Let's do some simple math.

The recipe mentions that you should start at 1.095 and you started at 1.050. So you are .045 short.

The must was now at 1.020 so you should add the .045 and add sugar to the 1.065 mark.

Now let me see if that is right........
1.095 will give about 227 gram per liter
1.050 will be 110 gram sugar per liter
difference 117 gram sugar short

1.020 is 32 gram sugar per liter
1.065 is 149 difference 117 in the plus so right at the ball mark.

However when fermentation starts sugar is transformed into alcohol. Alcohol has a lower SG as water and therefore will give a lower SG reading as plain water and sugar would do.
Therefore I would aim a bit higher like 1.070 or even 1.075.

Broy remember too, you now have bubbles so they will want to stick to the hydrometer and float it, thereby giving you an off reading. Float your hydro and tap it and spin it to dislodge the bubbles from it for a more accurate reading.
Right on the nose Troy, I forgot about that.

Is there a limit to when I shouldn't be messing with the sugar anymore? For some reason your latest suggestions didn't show up this morning so I took mmadmikes advice and added 2 cups. That raised it to about 1.030. It also says that after 5or 6 days (it's been 7 days) when the SG reaches 1.030 the fruit bag should be pressed and the liquor is racked into a secondary with an airlock. So now I'm wondering if I should bring the sugars up to 1.070, as you suggest while it's still in the primary or add the sugar and then transfer it right away. Hey, this is a lot more complicated than making beer. Why not rocket fuel; sounds like rocket science. Thanks for everybody's help.
There really is no bad time. When making sparkling wine we let it finish fermenting and then add sugar and throw it all in a bottle to ferment again causing thhe carbonation. Just dont let it sit too long after it has finished fermenting or the yeast may not want to go back to work.
Sorry, let me convert that for Luc. I added about 400 grams this morning. I just checked it tonight and it's at 1.020. Originally there were about 9 Kg of grapes and 8.2 liters of water.
Broy, besides "pressing the bag", you want to be sure to press that bag under the must, dunk it, if you will, at least once a day, twice is better.

This is one reason we don't do the primary ferment in carboys.

I use a plastic potato masher sprayed with sulfite solution.