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jayhkr

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Hey everyone! It’s been nearly 3 years since I’ve made any wine but this year I’m getting back into it! Already have a “super sugar method” frozen Welch's in secondary and am trying a 100% juice white grape that I want to ferment dry then try my hand at back sweetening. Not to mention I have 3 or 4 other recipes I have planned. Anyway, my question is on acid testing. I have an acid test kit from 3 years ago and I see no expiration date on it, so I tried it on my red “super sugar” batch. It took nearly 12 cc’s of Sodium Hydroxide before the color didn’t change any further. That would be 1.2% which is about double what it should. Could it be the kit, the wine, or just what it is?
 

Johnd

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Hey everyone! It’s been nearly 3 years since I’ve made any wine but this year I’m getting back into it! Already have a “super sugar method” frozen Welch's in secondary and am trying a 100% juice white grape that I want to ferment dry then try my hand at back sweetening. Not to mention I have 3 or 4 other recipes I have planned. Anyway, my question is on acid testing. I have an acid test kit from 3 years ago and I see no expiration date on it, so I tried it on my red “super sugar” batch. It took nearly 12 cc’s of Sodium Hydroxide before the color didn’t change any further. That would be 1.2% which is about double what it should. Could it be the kit, the wine, or just what it is?
Most probably, your NaOH has lost its potency and needs to be replaced. I typically replace mine yearly, just before fall grape harvest.
 

jayhkr

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Ok, thank you. Since it doesn’t have an exp. date on it I wasn’t sure. Appreciate the feedback!
 

Ajmassa

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Ok, thank you. Since it doesn’t have an exp. date on it I wasn’t sure. Appreciate the feedback!
New NaoH came in yesterday. Had plenty left but was well over 1 yr old. (And results seemed off)
New bottle actually has an expiration date on it. And the QR code from the bottle also shows the manufacture date. 2 year total shelf life. So considering time lost before in possession, replacing yearly seems like best bet unless ya have an exp. date. IMG_0090.JPG
IMG_0091.JPG
 

Ajmassa

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Yep. Always enjoy a stop at the local shop. Over the years I got pretty friendly with the guys at my shops. (I’m wearing my Philly Homebrew T-shirt right now actually lol) Usually ended up sampling their wines and beers and just shootin the shit for a while.
I support them as much as I can. But I moved further away from my main shop, and another closed last year so don’t get to swing by as often now.
 

jayhkr

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Agreed, there are 2 in my City I know of, but I’ve only been to one since it’s closer. I noticed the shop I go to has added a few new employees I need to get reacquainted with. Unfortunately they don’t have a taste test bar like yours.
 

Rice_Guy

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You are dealing with a weak base (sodium hydroxide) which will react with CO2 from the air. If it is sealed it will last forever, however every time you open the cap you let more CO2 in which reacts, This will be faster the more empty volume in the bottle. The real shelf life is proportional to how long/ how many times you use it.
Think of it as small scale ocean acidification, , the QA lab runs a standard acid every week, , and keep using NaOH with a small math correction.
 

Rice_Guy

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Another note, we (industry) typically add citric acid to a 100% juice blend since it will make an excessive reconstitution (ex 50% was ice that melted) still score OK in a taste panel. I don’t have any Welches in the freezer to check the label. Welches white grape should be northern grown Niagara which has enough vacuum evaporation to strip most of the foxy flavor off.
 

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