SpGr

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Ernest T Bass

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It's me again? I have two one gallon batches of must working. First batch is Peach- 2 1/2 lbs of peaches, 1 campden tables (Crushed), 1 gallon water, washed, pited and sliced thin, 4 1/2 cups of sugar, 1 1/2 teasoiib acud blend, 2 teaspoons Petic enzyne. Second day added one pack of yeast (Red Star-premier cuv'ee) and covered with towel. This is when I took my first SpGr reading and it was 1.076. Starting date was 9/19 and today 9/23 the SpGr is 1.030.
The other batch is red grapes, all ingredents the same, this one was started a 2days later on 9/21. The SpGr was taken before the sugar was added on 9/22, and it was 1.080 and today 9/23 it is 1.065.
What should I do to get the alcohol content up, or should I do anything?

Thanks for any advice

Semper Fi

Later Bud
 
It still needs to finish fermenting. It will have to get down to 1.000 or lower. Remove your fruit @ 1.020 and let it finish fermenting. Stir twice a day.
 
I thought the alcohol concentration was "pose" to increase as the fermentation process continued. That you would put something like 12% in the carboy for the second fermentation??????????

Semper Fi

Later Bud
 
I thought the alcohol concentration was "pose" to increase as the fermentation process continued. That you would put something like 12% in the carboy for the second fermentation??????????

Semper Fi

Later Bud

ur alcohol increases as ur s.g. decreases. that's showing the yeast is eating up the sugar and producing the alcohol. i'd say ur right on track...
 
Sp Gr

Thanks, I went to Jack Kelley's web site and copied a chart that led me to believe that as the SpGr increases, the Alcohol increases. I must be reading the chart wrong. It says that a SpGr of 1.010=1.4 Alcohol and 1.135=18.3.
Am I reading it wrong or just don't understand what it is telling me?

Semper Fi

Later Bud
 
Thats only initial readings. The higher the sg you start with the more alc you will make. You said for the grape batch that you tookan sg reading of 1.080 before you added sugar, how much sugar did you add and what was the sg after adding the sugar?
 
Thanks, I went to Jack Kelley's web site and copied a chart that led me to believe that as the SpGr increases, the Alcohol increases. I must be reading the chart wrong. It says that a SpGr of 1.010=1.4 Alcohol and 1.135=18.3.
Am I reading it wrong or just don't understand what it is telling me?

Semper Fi

Later Bud

The potential alcohol increases as the specific gravity increases. 1.135 = 18.3% alcohol if the yeast reduces the specific gravity from 1.135 to 1.000
 
If you look at your hydrometer, an Original Specific Gravity of 1.076 gives you a Potential Alcohol of about 10.25%. Take the starting potential alcohol number & subtract the final potential alcohol number to get your actual ABV.

If your wine completely stops fermenting at 1.000, your finished wine will have an ABV of 10.25%:
10.25 minus 0 = 10.25.

If your fermentation stops at 1.020, your final ABV would be about 8.25%:
10.25 minus 2 = 8.25%

Once your SG gets below zero, you add the number in the potential alcohol column to your starting potential alcohol number:

If your final SG stops at 0.994, your ABV would be 12.25%:
10.25 plus 2 = 12.25%.

Your yeast will work on eating the sugar in the must every day, and that will lower that number a little bit every day. The specific gravity measures the amount of sugar in your juice. The longer your yeast eats the sugar (producing alcohol & carbon dioxide as byproducts), the lower that number on the hydrometer gets, and the higher the actual alcohol level in your wine gets.

The first thing you want to do when making a wine is to check the SG of the juice, before you start adding yeast or chemicals. If the SG is not high enough to give you an ABV that you desire, you add a measured amount of sugar to raise the SG to the proper level. For dry reds, I prefer 12.5 to 13.5% (SG of 1.095 to 1.100). For sweet fruit wines, I prefer 10.5 to 11.5% (SG of 1.076 to 1.086).

Besides the SG, there are a couple of other items you should check, before adding acid blend, etc. The first is the PH, and the second is the Total Acid Level. A PH test kit can be found for around $5, and an acid test kit for around $10. A lot of recipes call for adding acid blend, but the acid level really should be checked before adding any acid. The reason being is that in different parts of the country, where you have hotter or colder climates, the acid level in the exact same fruits will be completely different. Here in the Midwest (Indiana) our fruit tends to have a higher acid level than in Texas. For example, Jacks Cherry recipes call for 2 TBLSP of acid blend, but with my higher acid levels in my fruit, that would be too much.

With the PH level, you want a fairly low PH of 3.0 to 3.6 for a wine that will age in the bottle, because a lower PH will prevent spoilage critters from attacking your wine in the bottle and turning it into vinegar. A wine with a PH of higher than 3.6 should be drank fairly young, before it has a chance to spoil.
 
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Have I got the basic idea? I follow the recipe and before adding the yeast I take a SpGr reading and it is 1.080. I let the must work for about a week and take a SpGr reading and it is 1.027, that tells me that it is time to put in the jug with the air/lock and let it finish working, this make a month or so, but don't mess with it until it stops bubling. At that time my alcohol will be 10.9. If I have this assumption right? but say that my first SpGr reading is too low, what do I do, add more sugar and let it work a couple of days and check the SpGr again and continue adding sugar until I get it to 1.080? And is 1.080 the magic number I should alway shoot for?

Semper Fi

Later Bud
 
Not exactly. You want to get the SG up to the desired level BEFORE you add the yeast. If you let it work for a couple of days, then try to get the level up, you are not going to have an accurate reading, because it will have already started to eat some of the sugar, and will end up with a higher alcohol content than you want.

make sense?
 
Youn have the concept now, I dom agree with Allen above as to get the sg in the proper range before adding yeast so as not to complicate things. Most fruit wines are good with a starting sg around 1.085 -1.090. If making wine from graoes such as Cabernet Sauv. then youll want to up that to around 1.100
 
I try to shoot for 1.085. At this point you can step feed the yeast with sugar... I think Luc has a table on his wijnlog stating how many grams of sugar equaly 1% alc.
 
How low % Alcohol is safe?

I would really like to have the wine between 8 and 10 %. Anything wrong with having it that low?

Semper Fi

Later Bud
 
As long as you drink it fast no, just dont expect it to shelve for a few years at that low abv.
 
That's not bad for a fruit wine. Too much rocket fuel and you lose the flavor.
 

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