Made my Petite/Zin yesterday and after topping off to the six gal. mark, i took a gravity reading. It was only 1.090. i wanted it to be close to 1.100. I should have checked as i was puring the last half gal or so of water into the fermentor. Other kits I`ve done, have come out real close or right on the mark. So i added on cup of table sugar to the batch. I hope that it does`nt affect the flavor in the end. Has any one else experienced a lower than expected gravity reading?
That SG is a little low for what I think a Zin should be. It wil result in a wine of about 12.3% ABV.
Are you sure you thoroughly stirred the water and the juice together? They won't mix as easily as one might think.
What did the instructions say the starting SG might be?
That added sugar will be converted by the yeast to alcohol and CO2. It will not affect the taste other than what affect additional alcohol will make. Adding sugar is how one raises the ABV of any wine.
If you really want to raise the ABV:
First, make good and sure you thoroughly mixed your juice and water. Take another reading to make sure it really is 1.090.
Your fermentation just started, so you can still add some more sugar. Take out a half gallon or so of your must. Warm it up and add a pound of sugar to it. Stir until it is completely dissolved... completely! Get it back down to the same temperature of your fermenting must and stir it in to the fermenting must slowly but thoroughly. Take another SG reading. Repeat until you get the starting SG you desire.
Understand that when you add sugar, the over all volume of must in your fermentor is going to go up. That additional volume will end up as alcohol. That is acceptable in this case but don't get too close to the top. Just don't try to get a starting SG that is more than your yeast can handle. Any yeast supplied in such a wine kit should be able to handle an SG starting at 1.100.