Question on measuring OG for wine must

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HCWHunter

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I made some sweet wine from store bought grape juice and it came out OK but a little sweet tasting even though it fermented down to .996. I'm thinking the lack of tannins is leaving it sweet tasting so I added a cup of strong tea and am letting the remainder age for awhile. Now I'm fermenting my first wine from crushing actual grapes. How much does the pulp and skin in the must affect the OG? I thought I should be testing the juice itself as much as possible so I poured my sample through a sanitized coarse strainer to remove as much pulp and skins as possible. It occurred to me afterwards that there must be additional sugars in the pulp so how does that affect OG? I'm mainly concerned that my chaptalization calcs may be off and I added too much sugar. Any insight is greatly appreciated.

Thanks,
HW
 
The strained juice was only at 1.062 so I added table sugar to bump it up to 1.09. My target ABV was 12.5-13% depending on FG. I’m not that worried about too much sugar since my target isn’t that high, but I am really curious about how the pulp would affect the OG reading. I guess I should have checked OG with and w/o pulp and skins in the sample.
 
how much sugar did you add, and to how many gallons?

if it went totally dry beersmith tells me a FG of 0.979? but 0.996 would be 12.5% ABV which would put a strain on even wine yeast i think?
 
Well, my prior grape juice wine fermented down to .996 so I used that in my calcs. 3 gals. @ 1.062 looked like it needed a little more than 1 2/3 lbs. of sugar. So I added 1 1/2 lbs. sugar, mixed well and retested. I added 2 TBS more at a time and retested til I got to about 1.09 (the must was foaming in my test tube so hard to read). Commercial wine is normally 12 - 15% ABV so wine yeast wouldn't be stressed at 12.5%.
 
Commercial wine is normally 12 - 15% ABV


well seems like you've got the self confidence to figure this out...

i'd love to know the style of wine that you're reffering too with 15% ABV? best i could ever get even with turbo yeast was 16%...

and if you're talking about madiera, port, marsala...they spike those with brandy....
 
if it went dry after starting at 1.090, beersmith says 15% ABV, which most yeast can't handle....
I forgot to add in my prior reply that my prior grape juice wine started at 1.104 after adding about 2 cups of sugar and finished at .996. It still tasted a little sweet when done at 3 weeks but I let it go another week and it tested the same. I don't know if the yeast maxed out but have read that wine yeast will sometimes go up to even 18%. I added a cup of strong breakfast tea and am aging it further now. Keep in mind that store bought grape juice is going to make a sweet tasting wine anyway, but I like sweeter wines and wanted to do something different than the usual beers and ciders I have been brewing.
 
well seems like you've got the self confidence to figure this out...

i'd love to know the style of wine that you're reffering too with 15% ABV? best i could ever get even with turbo yeast was 16%...

and if you're talking about madiera, port, marsala...they spike those with brandy....
I'm no wine connoisseur by any means, I prefer beer and cider, but I got my range info here:

Alcohol Content in Wine and Other Drinks (Infographic) | Wine Folly

As I said, I'm just experimenting with something different. We have a grape vine growing at a property we own and I decided to pick some grapes and try making some wine before the birds and critters got them all.
 
now i want to know what yeast you're using? (for the batch that went from 1.104 to .996)
You know, you obviously know more about wine making than I do, but you never answered my original question about measuring OG for wine must. Do you try to remove the pulp and skins from the sample when measuring OG?

As for my wine yeast, I bought the cheapest wine yeast I could find on Amazon at the time which was Red Star Premier Classique.
 
but you never answered my original question about measuring OG for wine must. Do you try to remove the pulp and skins from the sample when measuring OG?

i'd use a refractomer. just takes a drop or two for a reading....
Red Star Premier Classique.

thanks, i'm going to give it a shot! :mug:
 
i'd use a refractomer. just takes a drop or two for a reading....


thanks, i'm going to give it a shot! :mug:
OK, so that's equivalent to just testing the juice w/o pulp & skins using a hydrometer. Anyway, that's close enough for me but I will test with and w/o some pulp and skins if I ever try to make wine from crushed grapes again. Turns out it's a lot more work doing it this way since I have to knock down the cap and stir several times a day! I'm not really complaining though, it smells great as the gasses escape and it gives me something to do while I wait.

I was using that wine yeast to make my various ciders but have switched now to ale yeast for that. This wine was a way to get some more use from the Red Star packets left over.
 
OK, so that's equivalent to just testing the juice w/o pulp & skins using a hydrometer.


pretty much, if you're testing with a hydro, i'd say let the thing sit for 10-20 minutes with the solids. so that it reaches it's 'comfort zone'?

and for the record, i don't make wine, but your Original question intrigued me...sweet tasting at 0.996 was a problem i had to toss around in my head!
 
The flesh of the fruit will release some sugar when it breaks down. You say you crushed the grapes, but did you also press them to extract the juice? I don't make grape wine, but I understand that that is the normal process. Either way, if you added the fruit pulp it probably would contribute some sugar.

With my fruit wines, I freeze and mash my fruit and add the fruit pulp in a nylon bag, along with some pectic enzyme. Then I give it 12-24 hours for the pectic enzyme to work and break down the fruit. After that I check the SG and adjust sugar levels as necessary.
 
pretty much, if you're testing with a hydro, i'd say let the thing sit for 10-20 minutes with the solids. so that it reaches it's 'comfort zone'?

and for the record, i don't make wine, but your Original question intrigued me...sweet tasting at 0.996 was a problem i had to toss around in my head!
These are concord grapes and the green (fresh) wine has a distinctly "grapey" flavor. I too was surprised at the taste after seeing and double checking the FG. That's why I let it go another week. I've since learned that is typical of wine made from concord grapes, like Manischewitz wine which is sweet.
The flesh of the fruit will release some sugar when it breaks down. You say you crushed the grapes, but did you also press them to extract the juice? I don't make grape wine, but I understand that that is the normal process. Either way, if you added the fruit pulp it probably would contribute some sugar.

With my fruit wines, I freeze and mash my fruit and add the fruit pulp in a nylon bag, along with some pectic enzyme. Then I give it 12-24 hours for the pectic enzyme to work and break down the fruit. After that I check the SG and adjust sugar levels as necessary.
I actually froze them first because I couldn't start fermenting right away after picking the grapes because I was leaving town and couldn't be around to knock down the cap and stir as required during primary fermentation. I figured that was a good thing anyway to help break down the cells and release more juice. After washing and sorting out the green immature grapes, I crushed the grapes in my bucket with a potato masher and by hand with sanitized gloves on. All the juice with pulp and skins are in primary for a planned 6 days. I actually have pectic enzyme which I planned to use in secondary fermentation to help clear the solids but I didn't think about using it in primary too to break down the pulp! Darn, I just read the label on the bottle and it specifically says to use on pulp to extract more juice! So I just added the recommended amount. This is my first wine from pulp, so lesson learned! Thanks!
 
You’re on the right path. Yes, measure without the solids. A coarse strainer is fine.
Indeed, get the pectin enzyme in there during primary.

Don’t be surprised to see a little bump in gravity after you press as there is usually some sugar captured in the pulp that must be squeezed out. This is usually an inconsequential amount.

Regarding the strong tea you mentioned to balance residual sweetness (either tasted or actual residual sugar, definitely tasted at that gravity!) - also consider some tartaric acid addition as another tool in the tool chest.
 
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