How much k-meta for country wines?

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BigDaveK

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I'm always refining my wine making and a few months ago I started using a 10% solution of k-meta. At first it was to deal with the small bottles used for excess from secondary. But of course it was only a matter of time for the rabbit hole to appear.

I've read white wines need more free SO2 than red wines. For example at a pH of 3.5, whites need 40 ppm and reds need 25 ppm. Quite a spread. Going by color alone my wines have a hint of color, shades of amber, rose, and some so dark you can't see through them. Here's the thing - right now I don't have the ability to test. I don't want to under dose and I'd rather not over dose. Should I go by color? Should I continue to use the equivalent of a Campden tablet simply because that's what "everybody" says to do?

I guess I'm looking for generic guidance until I can test.
 
The trouble with reading, is sometimes we over think things. Wine is forgiving.

I don't get too worked up about it. I've noted before that I take a 1/4 tsp of k-meta and mix it into 5 equal parts of water. Tsp's or whatever I feel like that day, add one 5th to each gallon and call it good. It has been noted, specifically by @winemaker81 that this is surprisingly reliable to keep a wine at 30 ppm.

Seems like a safe middle road for me. Especially if it is still trusted 41 years later...
 
The pH of the wine makes a difference in the amount of K-meta necessary to hit a target SO2. This is correct.

I learned to make wine in an era before home winemakers testing SO2 was possible. In that respect, both @Ohio Bob are dinosaurs. We are among the first killed in Jurassic World. Bob went 4 seconds before I did, and this was good, as he didn't have to watch me taking it. ;)

1/4 tsp K-meta for 19 to 23 liters works. This was developed by generations of winemakers figuring out what worked. It's not magic, it's practical experience, learned by our forebears and passed on.

Winemaking is an art, not a science. As I've said before, if it was a science, everyone would be making 100 point wines.
 
You guys are a hoot! I love this place!

Without testing I know I'll over or under sulfite a bit and I have to live with that. I'm wondering, though, about a couple of my high acid wines. With a pH around 3.1 I only need around 15 ppm free SO2. Using the accepted generic dose I'd be grossly over dosing.How would that affect flavor? I don't know!

I'm not going to lose sleep over this, believe me. I have no problem continuing to do what probably works. I've been reading a lot of enology papers - I find them crazy interesting! - but what is extremely distressing to me is that there's a mountain of papers about grapes and virtually nothing about non-grape wines, which I do. And like everyone here, I want to make a fantastic wine...but not with grapes.

Here's an example of one of my tangents from reading - current practice is to ferment dry and back sweeten. Prior to making my first dessert wine I thought I would need to back sweeten to balance the alcohol. They crapped out at around 1.010, don't need back sweetening, and to me the sweetness tastes better than that from using a simple syrup. I now know that yeast use glucose first, fructose when they're desperate and that's what's left over. Maybe there's something to the old recipes that use an extra half pound of sugar in primary to make a "sweet" wine?

I never thought my innocent idea to make wine would lead to all this!! 🤣
 
* color is not an indicator of how reactive the polyphenols are. If you are looking for a low tech indicator I would take astringent taste plus bitter taste plus experience (ex black raspberry gets astringent with time) plus if the fruit is advertised as a “super fruit”. . . . . If the polyphenols are reactive the crop fits into the same family as red grape. . . . . ex I have started to peel & taste skins of wild apples to look for bitters without the sweet notes masking the tannins. . . . transparent apple juices with high bitters are called vintage ciders since they can last for years.
* your original post looked at red and white grape as the same. BUT the varieties of white have been selected to produce lower pH and the varieties of red have been selected for higher pH combined with good tasting tannin (Tannin and acid balance against sweet flavor) which reacts to soak up oxidizers.
* I am a Vinmetrica owner, I mostly don’t use up the chemicals/ run free SO2 but just assume that the number is zero, ,,, it works. When I test the white grape the number tends to be low to trace.
* the chemistry of free SO2 is based on Ka (basically pH). The free SO2 gas is able to penetrate bacterial cell walls, once inside the cell it reacts with organelles killing the cell. sulphite form will not penetrate the cell wall therefore isn’t effective. Ka like pH is a log measurement of hydrogen ions.
 
Using the accepted generic dose I'd be grossly over dosing.How would that affect flavor?
When treating H2S, I dose with over 100ppm k-meta. This produced no noticeable effect, other than making the H2S go away.

The dosage can be very high without producing a bad effect. We don't dose that high because it is unnecessary, wasteful of the k-meta.

IME, the exact ppm is a useless number, when the wine is being dosed with 1/4 tsp per 19-23 liters
 
You guys are a hoot! I love this place!

Without testing I know I'll over or under sulfite a bit and I have to live with that. I'm wondering, though, about a couple of my high acid wines. With a pH around 3.1 I only need around 15 ppm free SO2. Using the accepted generic dose I'd be grossly over dosing.How would that affect flavor? I don't know!

I'm not going to lose sleep over this, believe me. I have no problem continuing to do what probably works. I've been reading a lot of enology papers - I find them crazy interesting! - but what is extremely distressing to me is that there's a mountain of papers about grapes and virtually nothing about non-grape wines, which I do. And like everyone here, I want to make a fantastic wine...but not with grapes.

Here's an example of one of my tangents from reading - current practice is to ferment dry and back sweeten. Prior to making my first dessert wine I thought I would need to back sweeten to balance the alcohol. They crapped out at around 1.010, don't need back sweetening, and to me the sweetness tastes better than that from using a simple syrup. I now know that yeast use glucose first, fructose when they're desperate and that's what's left over. Maybe there's something to the old recipes that use an extra half pound of sugar in primary to make a "sweet" wine?

I never thought my innocent idea to make wine would lead to all this!! 🤣
 
Adding extra sugar will just up your alcohol unless you use a low threashhold yeast. I’m curious what yeast you used that stopped at 1.010.
 
How much wine are we talking about?
The wines I made that were a hit didn’t last nearly as long as I thought they would. I probably would have been fine to shoot for low and would have been healthier for it as I discovered how sensitive I am to sulfides.
 
Adding extra sugar will just up your alcohol unless you use a low threashhold yeast. I’m curious what yeast you used that stopped at 1.010.
The yeast stopped because there was too much alcohol. Step feeding coaxes the yeast to go a bit past their threshold, giving the little sugar junkies multiple manageable doses rather than one massive deadly dose. Adding all the sugar at once would give an SG somewhere around 1.170+. I used 1118 which I believe is rated for 18%.
 
Here's an example of one of my tangents from reading - current practice is to ferment dry and back sweeten. Prior to making my first dessert wine I thought I would need to back sweeten to balance the alcohol. They crapped out at around 1.010, don't need back sweetening, and to me the sweetness tastes better than that from using a simple syrup. I now know that yeast use glucose first, fructose when they're desperate and that's what's left over. Maybe there's something to the old recipes that use an extra half pound of sugar in primary to make a "sweet" wine?
So, my brother in his infinite wisdom, added a crap ton of sugar to his first ferment without testing gravity. (this year. we are noobs) I asked him how much, and he said 7lbs, to 2 gallons. Now this was a foraged grape so everything is off, but I did the math and the gravity was probably no less than 1.161 at the beginning of his fermentation. It some how made it through, I think it could still be fermenting 🤣 but at 9% abv we tried it and it was a sweet wine. So since then I have been asking the question, "If we know we max out at 14 % abv or about, why cant we add more sugar up front and make a sweet wine without back sweetening?" Granted we don't know where it will end up, but we know it would stall at or around 14% right? And with SO2 that should help eliminate other microbes feasting right? I haven't really heard a good argument against this, yet...
 
So, my brother in his infinite wisdom, added a crap ton of sugar to his first ferment without testing gravity. (this year. we are noobs) I asked him how much, and he said 7lbs, to 2 gallons. Now this was a foraged grape so everything is off, but I did the math and the gravity was probably no less than 1.161 at the beginning of his fermentation. It some how made it through, I think it could still be fermenting 🤣 but at 9% abv we tried it and it was a sweet wine. So since then I have been asking the question, "If we know we max out at 14 % abv or about, why cant we add more sugar up front and make a sweet wine without back sweetening?" Granted we don't know where it will end up, but we know it would stall at or around 14% right? And with SO2 that should help eliminate other microbes feasting right? I haven't really heard a good argument against this, yet...


The only good argument against it is that you don't have control over the sugar level or the ABV. Nonetheless, you may find a pleasing result from your attempt. You may want to review this thread:
Welch's concord with the super-sugar method
 

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