Proper Sanitization Dosage

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cmason1957

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Yes that makes complete sense. What about the addition of citric acid. I found this and have always been confused about the citric acid addition.


"Put about 2 or 3 inches of water in the bottom of your carboy, then add 1 teaspoon of potassium metabisulfite. It is also very important that you add 1/2 teaspoon of citric acid along with it. Without the citric acid, the SO2 will not release readily enough to do the sanitizing."
I always mix up my kmeta with citric acid. 2 tbsp kmeta + 1 tbsp citric acid per gallon.
 

winemaker81

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"Put about 2 or 3 inches of water in the bottom of your carboy, then add 1 teaspoon of potassium metabisulfite. It is also very important that you add 1/2 teaspoon of citric acid along with it. Without the citric acid, the SO2 will not release readily enough to do the sanitizing."
My understanding is that any acid product lowers the pH to make the K-meta more effective. I've never heard that it's a requirement.
 

Rice_Guy

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@Linetec in the old days a wine maker went to the village well for clean water to wash the wooden wine making tools. ,,,, simple clean water is excellent at removing microbial load, so you can relax.
* the active ingredient in metabisulphite is free SO2 . This is an ionization reaction which is driven by the pKa of meta, ,,,ie point where half is in the free form, ,,, or pH of 1.4. Therefore more good stuff is there if the solution is acidified. We use clean water with little buffering so a little acid is enough but in reality a lot of acid won’t hurt so go ahead. We add meta to wine as an antioxidant so rinsing to remove five ml in the bottom is never going to be seen in the calculated ppm sulphite in a finished wine.
* the buffering capacity of tap water is low, it will work as well as distilled water, ,,, if you are concerned you could add acid to get pH 1.0 but it is more effort than it’s worth, over kill works.
* metabisulphite is extremely corrosive! It will destroy metals therefore rinse it off stainless tanks. Meta slowly oxidizes many types of plastics so every ten years plan on replacing plastic equipment. Free SO2 is toxic, so avoid breathing excessive quantities, ,,, but small quantities are relatively safe as a sanitizer so one doesn’t need to be licensed to buy it.
* Star San is a good sanitizer and safer than SO2.
In a food canning line, treating the food long enough to achieve nine log cycles of kill is considered sterile. For reference simple washing stainless equipment in cold tap water will remove five log cycles of bacteria. Hot water adds another and soap in the water a second (ie 7/9 of the way to commercial sterility) For the micro lab tools are sterile if they have been retorted for 45 minutes at 121C/ 15 psig live steam. Another method for loops is to heat them in a Bunsen burner till red.
For me,, first an foremost the tool must be clean, ,,, free of obvious mechanical dirt. This can be done in wine or a fluid like milk with a spray hose. A second requirement is that the tool should not be wood or other porous material. . . . . I will rinse siphon tubes and bottles with K meta sanitzer, but don't see the point on tools for punching down the cap.
The must is already a mix with some bacterial contamination. I think of it as “a multi component food preservation system”. Over 10% alcohol does wonders, pH knocks out many bacterial families, free SO2 is a barrier, anaerobic conditions / CO2 prevents most organisms, fast growth of selected yeast , ,,, and I guess I consider these more important to the wine
the key points keep meta off metal and SO2 is toxic so ventilate
 

cmason1957

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Distilled water or tap water?
I use tap water for just about everything, except for adding to kits to get to the proper level. I believe I read somewhere that the K-meta neutralizes any concerns about chlorine in tap water. If it tastes okay to drink, then it's fine for winemaking is I believe the quote, but ask 10 winemakers get 11 answers.
 

wineview

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I use tap water for just about everything, except for adding to kits to get to the proper level. I believe I read somewhere that the K-meta neutralizes any concerns about chlorine in tap water. If it tastes okay to drink, then it's fine for winemaking is I believe the quote, but ask 10 winemakers get 11 answers.
[/QUOTE

I noticed my tap water made Star San cloudy and I’ve been told less effective. Distilled kept it crystal clear. So I was wondering if the same applies to K Meta. Sounds like it doesn’t.
 

Rice_Guy

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chlorine in an oxidized state, ,,,, ie combined with organic matter ,,, should not produce TCA and has a high redox potential.

chlorine in a reduced state (redox potential) as hypochlorite (bleach) or chlorine gas added by a water treatment plant will contribute a risk for TCA. Excessive chlorine as in swimming pool will volatilize and present a flavor risk.
Metabisulphite is also a low redox state chemical, Craig I would check that source.
I read somewhere that the K-meta neutralizes any concerns about chlorine in tap water.
 

wood1954

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This is quite the eye opener, I’ve been using Starsan for years and never knew it only was good for an hour. I usually make a gallon mix at a time, So either it works or I’ve been lucky. I’ve always thought that So2 degraded faster so didn’t use it for sanitizing. I guess I’ll mix up starsan as needed till it’s gone, then switch to So2.
 

cmason1957

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chlorine in an oxidized state, ,,,, ie combined with organic matter ,,, should not produce TCA and has a high redox potential.

chlorine in a reduced state (redox potential) as hypochlorite (bleach) or chlorine gas added by a water treatment plant will contribute a risk for TCA. Excessive chlorine as in swimming pool will volatilize and present a flavor risk.
Metabisulphite is also a low redox state chemical, Craig I would check that source.
Well here's one source that seems to maybe support that kmeta removes chlorine from water. It does indicate sodium metabisulphite, and maybe that is different, my chemistry background isn't recent and isn't much.

 

cosmyccowboy

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I mix 3 Tbsp K-meta in a gallon jug.
I keep a couple jugs of it ready and fill my spray bottle from them.

I spray down everything with the spray bottle - buckets, lids, spoons, graduated cylinders, hydrometers, bowls, auto-siphons, tygon tubes, .......
I pour kmeta into tygon tubes and work it back and forth to coat the insides.
I use glass pebbles to raise the level of the wine in carboys - they soak in kmeta a while beforehand.
I put corks in a stainless steel bowl and spray them down with kmeta, cover with paper towel and spray it down with kmeta to create a kmeta "gas chamber" for the corks.
After I've cleaned a 6 gallon glass carboy, I pour a gallon of the Kmeta solution into the jug, cover the opening with one hand and shake the carboy. I pour the kmeta back into it's jug and cap the carboy. It's stored with plenty of residual kmeta solution still in it. When I need it, it gets fr

I’m a newbie so my experience is on the beginner level, let me say that at the start. But I have to ask the question, is the obsession with sterile necessary? I understand you want your equipment clean but have you ever harvested grapes from the vineyard? I mean the fruit is full of bird shit, bugs, spider webs, spiders, dust, dirt and God knows what else?
 

wineview

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You caught my eye when you said you spray your corks before bottling. I was taught to always keep the corks dry. So….I mix a quart of Sodium Metapsulphite pour it into an empty juice pail. Place a colander into the pail so the solution is under the colander. Place my corks in the colander and put the lid on the pail. The theory is that the fumes will sanitize the corks and they stay dry. Seems to work for me.
 

winemaker81

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But I have to ask the question, is the obsession with sterile necessary? I understand you want your equipment clean but have you ever harvested grapes from the vineyard?
First -- we are talking sanitizing, not sterilizing. These are vastly different. Sterilization is killing 100% of the organisms. Sanitization is removing and/or killing the majority of the organisms to greatly reduce the likelihood of them growing in sufficient numbers to offer a threat.

Fermentation, especially with commercial yeast, crowds out most competing organisms. However, there is a multitude of yeast, bacteria, and other micro-critters that can survive the low pH, high alcohol environment. Sanitization greatly reduces these threats to the wine.

This is not an obsession -- it's a best practice. After you've tossed a carboy or 3 due to contamination, you'll agree.
 

wineview

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First -- we are talking sanitizing, not sterilizing. These are vastly different. Sterilization is killing 100% of the organisms. Sanitization is removing and/or killing the majority of the organisms to greatly reduce the likelihood of them growing in sufficient numbers to offer a threat.

Fermentation, especially with commercial yeast, crowds out most competing organisms. However, there is a multitude of yeast, bacteria, and other micro-critters that can survive the low pH, high alcohol environment. Sanitization greatly reduces these threats to the wine.

This is not an obsession -- it's a best practice. After you've tossed a carboy or 3 due to contamination, you'll agree.
20 years ago I had to dump 5 gallons of beer and it just killed me.
 

David Violante

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I have a starsan spreadsheet that I use. For 16oz use 0.7ml. Love that it’s both metric and imperial... and called “imperial”…

image.jpg
 

bstnh1

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Does anyone have a source for a GOOD bottle brush? The last couple I bought lasted for 6-8 bottles and then the britles flattened out.
 

stickman

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@bstnh1 good question, I assume they are all made in the same place, so it may be a question of luck with getting a good production run or not. A few years ago they seemed to be in short supply, but I did find a couple at a home brew shop and so far they are working fine. I cut the end off and epoxy a 1/4" stainless steel tube (actually a cheap stainless straw) over the stem to allow a better fit in the drill chuck.
 

bearpaw8491

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I use K-Meta to stun wild yeast and a very few other things but Star San is my go-to sanitizer and has been for about 8 yrs. I mix 3 ml in 1/2 gal of non chlorinated water and store in the glass container (1/2 gal Mason jar). I pour the premix into my sprayer and spritz surfaces, equipment. I pour some of the mixture into carboys, primaries ect and slosh around to sanitize. I have found as long as the solution remains clear the effectiveness is unaffected. The lack of 10 minute wait time is worth the investment in a small bottle of Star San. I've never had any contamination or microbial problems in my years of use. Hope this help.
 

wineview

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I use K-Meta to stun wild yeast and a very few other things but Star San is my go-to sanitizer and has been for about 8 yrs. I mix 3 ml in 1/2 gal of non chlorinated water and store in the glass container (1/2 gal Mason jar). I pour the premix into my sprayer and spritz surfaces, equipment. I pour some of the mixture into carboys, primaries ect and slosh around to sanitize. I have found as long as the solution remains clear the effectiveness is unaffected. The lack of 10 minute wait time is worth the investment in a small bottle of Star San. I've never had any contamination or microbial problems in my years of use. Hope this help.
I am in total agreement.
 

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