A couple questions on my first fresh fruit batches

[darrenct83]

I am making my first wine from grapes. It will be ready to stabilize very soon and I have a couple questions.

1) A)Do I need potassium sorbate or fining agents to stabilize? Can I just use potassium metabisulfate if I do not plan on sweetening the wine?
B)Same question, different wine. I have a wild berry wine(Huckleberry/Wild Raspberry/Thimbleberry) going. What will be needed to stabilize it?


2)The grapes were picked semi-prematurely and I had to add sugar to reach my starting gravity. The grapes are wine grapes, but I do not know the variety. The gravity is down to 1.002 and the wine tastes very tart. I believe this is from the premature grapes. Am I correct? Will this tartness mellow out after aging? If so how long?

 

[ellijaywinemaker]

You will have to ferment to dry. I would use the Potassium met to stablelize it and a fining agent to clear it. Scents you are not going to sweeten it back then you spould be good with out the sorbate.

 

[jet]

...
The gravity is down to 1.002 and the wine tastes very tart. I believe this is from the premature grapes. Am I correct?
...

I'd say yes. As grapes ripen the acid level drops as the sugar level climbs. Pick too early, and you've got high acid and low sugar. Pick too late and you have low acid and high sugar.

 

[Tom]

Sorbate is not needed if not bottling right away BUT, aging is best before bottling. Make sure you degas.

 

[Wade E]

No sorbate is needed if you are not sweetening the wines. If you are going to sweeten either of these 2 batches then both sulfite and sorbate are needed. If that wine is very tart then you may need to cold stabilize it or use an agent like Potassium Bicarbonate to lower the acid and then cold stabilize it to precipitate the excess acid out. If its a red wine that you made from grapes(you didnt specify if its a white or red) then you may want to do a Malo lactic fermentation on it which will eat up some of that tart (Mailc) acid and turn it into a much smoother (Lactic) acid. Think of the malic acid as a Green apple and the lactic acid as Milk which is much smoother. You can onkly do this malo lactic fermentation (MLF) if you have not added any sulfites yet after fermenting and you can never add any sorbate as sorbate and MLF = a geranium smell and taste in your wine.

 

[darrenct83]

Thanks Wade. The grape wine is a blush colored wine. The person I got the grapes from bought the house with the vines so he knows nothing about them. I will probably use the potassium bicarbonate method. Is cold stabilizing just stabilizing normally, but doing it in the fridge?

I will probably get some potassium bicarbonate, but I am curious if sodium bicarbonate could be used. It is almost identical in chemical structure, and much more readily available. Does the sodium produce off flavors or adverse reactions that potassium does not?

 

[JohnT]

If you picked the grapes too early, I would make sure to test the acid level. It may be too high.