SpGr

From what I read, SpGr is very important, it tells you a lot of things. As for the first SpGr, when is taken? The way I understand it, you, wash your fruit, Cut it up, smash it up some, add some water, mix all your ingredent (pectin emzine, acid blend and sugar and campden) in the rest of your water and pour that over your fruit. Let that work for 24 hours, then add your yeast.
Now, at what point do you take your first SpGr reading? When do you take your second reading. Alcohol potential means what? What the alcohol content will be when finished or alcohol content at time of reading ? I assume you would add water if it is too high, what do you do if it is too low?
If you reply to this question, please go into great detail, and at about 3rd grade level. I want to learn how to make good wine, and I would like to learn right the first time. Please make it very simple & Thanks for your reply

Semper Fi

Later Bud

Bud:

First reading...before you pitch the yeast. If you are adding sugar, take it before and after adding the sugar to understand the increase. That will help to ensure the desired alcohol level.

Mandatory reading before pitching the yeast. This is your starting sg for the alcohol calculation.

Next reading...basically anytime. I usually wait a week, but many others have trouble waiting 24 hours. Monitoring progress is a good thing. But patience is better.

Final reading before stabilizing the wine. This is the ending sg for the alcohol calculation.

POTENTIAL alcohol is what it says...potential. It's not current alcohol. If the wine ferments to 1.000, then it is what the alcohol will be. For example A wine that starts at sg 1.080 is a potential alcohol around 10.5%. When it starts the current alcohol is 0%.

Steve

Agree with cpfn! You dont ever want to add sugar or for that matter acid blend without first taking readings because you may not want to add sugar. The sugar contant of fruit can change considerably from area to area thus making adjustments different. Picking fruit earlier or later will increase or decrease the amount of sugar needed and also acids. Picking early usually results in high acid amounts and low sugar amounts. If picked early your acid can already be very high and following a recipe and adding more can make your juice very hard to ferment and stress the yeast and create off flavors if it even ferments at all. Not adding enough acids can also become a problem as your wine will be flabby and tasteless and can create an environment where bacteria will thrive.

Stabilizing

Is stabilizing when you add the campden tablets just before you bottle it?
I also read on the inter-net where you want your alcohol content in your finished wine to be at least 12%. Also, what do I do, if after a week the SpGr indicates 9.0%, & does that mean that my final product will be 9.0%?
My hydrometer has 3 scales, SpGr, % Alcohol & Brix. I have some muscadine
must that is 5 days old and shows 7 %. What say you to all of this?

Semper Fi and Thanks

Later Bud

Stabilizing is when your wine is all done fermenting An sg usually around 1.000 or hopefully below that) and has not moved for at least 3 days and then you add both potassium or sodium metabisulfite in powder form or campden tablet in pill form and then also add potassium sorbate. the sorbate is what makes the yeast not start a fermentation over if you add more sugar to your wine. If after a week your wine is at 9% and is not moving at all for a few days thats what we cal a stuck fermentation. What was then starting gravity or potential alc on this batch and is it moving slowly or not moving at all? If its not moving at all and you started with 12% then we need to do something about this like get the temp up if its below 75* and stir it up and add nutrient and even energizer. If the temp is around there then we will need to do something more drastic like make a yeast starter which consists of taking something easy to ferment like grape juice or apple juice and add yeast to it with nutrient and get it going good. We do this in small amounts like a packet of yeast and 2 cups of juice in a gallon jug. Then once its going good we add about about 1/2 cup of the wine you are trying to ferment until thats going good and again add another 1/2 cup of the wine. Doing this acclimates the yeast strain to the problem-some wine. Once thats going good again we will add another 1/2 cup again and once thats going good we will take this whole vessels worth and add it to our batch in a temp of about 75* give or take 2-3* as this temp is the best for wine yeast especially one thats having a hard time. I strenuously suggest the use of both nutrient and energizer especially in fruit wines Meaning (non-grape) case they lack the amount of nutrients that grapes have making grapes the perfect environment for yeast.
Potential alc scale on a hydrometer - To understand how to read this.
est say you start with a reading of 12% potential alc. and your wine stops at 5%. That means you now have 7% abv. If it fermented all the way you would have 12%.
I hope that clears it up for you.

Bud:

A lot of beginning wine makers have problems reading a hydrometer, and understanding specific gravity.

When it comes to specific gravity, remember the old adage "what goes up, must come down".

Specific gravity is a measure of the sugars in the must. Specific Gravity is NOT a measure of the actual alcohol. As you add fruit and sugars to your mix, the specific gravity will go up, representing an increase in the sugars present. Since the sugars will convert to alcohol during fermentation, the POTENTIAL alcohol also increases.

Before the yeast is pitched, the sg and the potential alcohol will be at their highest. While the actual alcohol will be at ZERO.

As fermentation starts, the sg will start to drop and the realized alcohol will increase. When fermentation is complete, the alcohol level will be at it's highest, and the sg will be at it's lowest. The potential alcohol will also be at it's lowest (there's no more sugars to convert into alcohol) and will be zero, or even negative.

Here's an example...

Start...sg 1.100, potential alcohol 13.3%, actual alcohol 0%.
Midway...sg 1.050, potential alcohol 6.65%, actual alcohol 6.65%
End...sg 1.000, potential alc 0%, actual alcohol 13.3%

Actually fermentation will probably continue...
sg 0.994, potential -0.8%, actual alcohol 14.1%

Hope this helps, Steve

Very well put Steve!