reducing acid question

Hello all.

I was given about 80 pounds of grapes from an old local winery that has gone out of business. I was told they are ferdonia or Ives grapes. I have added sugar to adjust the sg to 1.090. Since I have found that they are similar to concord grapes in the wine making process, I probably should of diluted with water before fermentation. I did not. Now that the wine is finishing up the primary fermentation stage, I was wondering if I can add water post fermentation without affecting flavor too much. If I do, what should acid reading be at? Thanks in advance for any help you can give.

why add water.? the acid value could be anywhere. if acidity is the problem after doing taste test, add sugar syrup under bench trial conditions to reach a balanced wine. wait until wine is at least a month or longer.

In all likelihood, if you sugar is very low, the grapes are under ripe and high in acid. Of course, this all depends on the variety of grape.

I would go out and get an acid test kit and get an idea of what the acid is like. you could potentially add sugar water to reduce the acid, but this should be done before fermentation ends.

There are a few good ways to reduce acid without adding water (water will dilute your flavor).

1. Yeast: GRE and others will eat the malic acid during fermentation. This is my method of choice for concord and niagra, but it sounds like you are past that point.

2. MLF: if your pH and SO2 are in the right range you can try after primary. Might try this on a small. Portion to see if you can get it started and if the results taste good to you.

3. Potassium carbonate & cold stabilization. Can be done after primary but you should really have a pH meter in hand and a cold basement or fridge to do this successfully.

4. Sugar (+2) can bring most high acid wines into balance. Make simple syrup and do some small taste tests to see how much it takes.

I know everyone meant to say this but, if you are going to use sugar to balance the acid (except for the JohnT comment), make sure fermentation is finished and stabilize the wine with Kmeta and Sorbate before adding the sugar, or the active yeast will eat all your sugar up!