Questions about SG for a beginner

[Sweeps]

I am new to winemaking (and brewing in general) and had a few questions about SG.

1. I started a strawberry wine on a Monday, and checked the SG on Saturday and it was just about 1.0, so I racked it. Is this okay? Most things I've read suggest 1.030.

2. For my first test batch (Pineapple) I didn't even test SG at all until ~2 weeks after I racked it, and when I tested it, it had a reading of about .994. Is this bad? Is it going to be ****?? HELP

3. How often do you check SG during primary fermentation and secondary fermentation?

Any help would be appreciated for such a novice

 

[Chef-Ryan]

The lower the SG the less sugar there is.. water is at approximately 0.998. But because sugar increases the density of the liquid it will lead to higher numbers the more sugar you have. Alcohol being less dense than water will cause the numbers to drop as you ferment and if fermented dry (no sugar left) can have SG lower than that of water. I don't have a personal answer to question but seems like it should be fine and question 2.. your lower SG is fine just bone dry.. and will be fine assuming you ensure no headspace and use appropriate measures to ensure quality over time (things like Campden or k-meta) and for fermentation I check daily because as a fermentation progresses you can see the speed of the ferment and actually tell when a ferment is slowing down and when you have the same reading 3+ days in a row either the yeast dies because they are done with sugar or you have a stalled ferment.

I hope this helps and makes sense.. if not maybe i need more coffee and to try to explain it better.

 

[CatawbaCat]

1. I started a strawberry wine on a Monday, and checked the SG on Saturday and it was just about 1.0, so I racked it. Is this okay? Most things I've read suggest 1.030.

You're missing a few decimal points. 1.0xx?

For most wines I ferment them dry before I rack to carboy, but racking before then is fine also, as long as it's under 1.020, in my experience.

2. For my first test batch (Pineapple) I didn't even test SG at all until ~2 weeks after I racked it, and when I tested it, it had a reading of about .994. Is this bad? Is it going to be ****?? HELP

You'll probably be okay, depending on when you racked it. It's dry *now*, but if it runs dry in primary and it's not racked to carboy reasonably soon, you run the risk of oxidation. You don't mention when you racked it. And without a starting gravity (SG) we have no idea what your ABV (alcohol by volume) is. A lower ABV can affect the wine as well.

3. How often do you check SG during primary fermentation and secondary fermentation?

In primary, I check every day, or skip the first few days, and then every day. Because I ferment to dry ordinarily, I don't check in secondary except to make sure the gravity is the same before I rack again. I have one I just fermented to 1.010 and racked, which has set in the carboy for about 6 days now, and have not checked the gravity yet.

This hobby is great for being lazy and taking your time.

 

[Sweeps]

You don't mention when you racked it. And without a starting gravity (SG) we have no idea what your ABV (alcohol by volume) is. A lower ABV can affect the wine as well.

My bad, I racked it 2 weeks ago, so I just tested it over the weekend and that is the reading I got, so it hasn't been too too long

 

[bernardsmith]

The lower the SG the less sugar there is.. water is at approximately 0.998.

Sorry, Chef-Ryan. I think you need more coffee. Water is precisely 1.000. The density of all other solutions/liquids are compared to water. But as you say the less sugar there is in a solution the closer the specific gravity (AKA density) is to water. Alcohol is less dense than water so the specific gravity of solutions that include alcohol (eg, wine) will tend to be below 1.000 if they have no residual sugar (dry wines).

 

[Sweeps]

So if I want a sweeter, more fruity tasting wine, I would want the SG to be ~1.000+ right? I'm assuming that would have to be sweetened closer to bottling?

 

[GeneDaniels1963]

I think wines are considered sweet with a SG of around 1.015 or so. But make sure you read up about stabilizing wine before you try to backsweeten. If not you will great a huge mess and lose your wine in busted bottles!

 

[Chef-Ryan]

Sorry, Chef-Ryan. I think you need more coffee. Water is precisely 1.000. The density of all other solutions/liquids are compared to water. But as you say the less sugar there is in a solution the closer the specific gravity (AKA density) is to water. Alcohol is less dense than water so the specific gravity of solutions that include alcohol (eg, wine) will tend to be below 1.000 if they have no residual sugar (dry wines).

The density of water at 20 ̊C is 0.998204 g/cc and that density translates to the same value in SG. But at 4c (40f) yes the density of water is 1.00 (colder temps make things denser usually)

 

[Sweeps]

UPDATE: I bought a refractometer and took some readings today

As of 2 weeks racked, Pineapple: 1.015 SG

As of 2 days racked, Strawberry: 1.023 SG

That seems a lot more correct, my hydrometer readings were both a little over .020 SG off. I double checked just to make sure I was using the refractometer right.

Wasting 2 or 3 drops of wine > an entire test tube