Baking Soda

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WIski
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Re: Baking Soda

Post by WIski »

Alchemist75 Wrote;
There must be trace amounts of copper in anything condensed on copper. Maybe not much but perhaps enough to produce that blue color. I know some stills are designed in such a way as to avoid condensing the vapors on copper. A short column packed with copper with a ss condenser coming off the top is intended to alleviate possible copper contamination. Some aspects of my gear can accomplish this as well....
Controversial as it is, there is some concern with the copper carry over. Personally I think I'm eventually going to swap out the copper PC for a stainless one. I have plenty of copper contact on the up side so I don't see any reason not to, other than time and expense. If I was just starting out I would have gone this route. Copper up, stainless down. :eugeek:

See below...........

http://homedistiller.org/forum/viewtopi ... =1&t=53217
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Re: Baking Soda

Post by Alchemist75 »

I know trace amounts of copper have been detected in some commercial spirits though only in small amounts. I'd say the only significant risk here, assuming your gear is decent, is a zinc/copper imbalance in your body over time. If you drink a lot it's probably wise to take a zinc supplement periodically.
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Re: Baking Soda

Post by Kareltje »

Or adding zinc in the path?

But that is going off topic, more for another discussion, maybe?
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Re: Baking Soda

Post by Alchemist75 »

I would imagine the zinc would oxidize fairly quickly in the worm rendering zinc oxide(s). Dietary zinc is largely presented as zinc gluconate or picolinate. These forms absorb much more completely into gastric mucosa, the oxide might not pass into the bloodstream so well...
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Re: Baking Soda

Post by Bagasso »

Alchemist75 wrote:I know trace amounts of copper have been detected in some commercial spirits though only in small amounts.
But according to this pdf, some pretty large amounts have been seen in homemade drinks. It doesn't go into detail but it would be a good idea to find out why there is this difference between homemade and commercial. I'm thinking SS on the down side but that is just a guess.
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Re: Baking Soda

Post by Alchemist75 »

What I've observed upon occasion is that if I don't thoroughly clean my copper between runs I get visible copper contamination in my spirit especially on stripping runs. Maybe it's a cleaning issue? Not sure but using ss or some other corrosion resistant material on the down comer is the obvious solution.
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Re: Baking Soda

Post by Bagasso »

Alchemist75 wrote:Not sure but using ss or some other corrosion resistant material on the down comer is the obvious solution.
I'm pretty sure some places still have full copper stills and they don't reach the extreme levels mentioned in that pdf so maybe a cleaning schedule/technique might help those who don't want to part with their copper porn.
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Re: Baking Soda

Post by Alchemist75 »

That's my guess based on observation. Too I would think you'd start losing the chemical benefits of copper without routine cleaning. I suspect the big boys stay on top of that kind of stuff.
Nonetheless, using a non copper down comer is probably the best bet to ensure purity. Keep your rigs clean kids.
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Re: Baking Soda

Post by FL Brewer »

I apologize if this a redundant, but I couldn't find it in the archives....

I had a problem trying to find sodium carbonate, but then found this youtube video that showed how you can make it by simply heating up sodium bicarbonate. https://www.youtube.com/watch?v=cpGEc-pLXN4" onclick="window.open(this.href);return false;" rel="nofollow

Couldn't be much simpler, and since sodium carbonate is so much more effective than bicarbonate, worth the minimal effort required.
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Re: Baking Soda

Post by RedwoodHillBilly »

FL Brewer wrote:I apologize if this a redundant, but I couldn't find it in the archives....

I had a problem trying to find sodium carbonate, but then found this youtube video that showed how you can make it by simply heating up sodium bicarbonate. https://www.youtube.com/watch?v=cpGEc-pLXN4" onclick="window.open(this.href);return false;" rel="nofollow

Couldn't be much simpler, and since sodium carbonate is so much more effective than bicarbonate, worth the minimal effort required.
Or you could go to Walmart or your local pool supply and buy some PH plus or PH up. These are commonly sodium carbonate. Read the label to be sure.
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Re: Baking Soda

Post by Kareltje »

I just buy washing soda in my supermarket.
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Re: Baking Soda

Post by Nunyo »

Question for those of you using baking soda in the low wines. How are you aerating? Everything I’ve read indicates that the sodium carbonate or in this case sodium bicarbonate (baking soda) should be added at least a week before the spirit run and the low wines should be aerated during that time. An aquarium pump and a stainless air stone seem like a logical solution. I know silicone is frowned upon here though I don’t know if silicone tubing such as the ozone safe stuff would be an issue with a 40% wash. Is copper tubing or stainless tubing the only safe means of providing air to an airstone or am I overthinking this all together?
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Re: Baking Soda

Post by Alchemist75 »

FL Brewer wrote:I apologize if this a redundant, but I couldn't find it in the archives....

I had a problem trying to find sodium carbonate, but then found this youtube video that showed how you can make it by simply heating up sodium bicarbonate. https://www.youtube.com/watch?v=cpGEc-pLXN4" onclick="window.open(this.href);return false;" rel="nofollow

Couldn't be much simpler, and since sodium carbonate is so much more effective than bicarbonate, worth the minimal effort required.
Yep, I prepare mine in a steel calcining dish on my gas stove. If you use a propane torch you can get the temp high enough to convert it to sodium oxide. Kick that into distilled water before it cools and you have sodium hydroxide which will really split the esters.
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Re: Baking Soda

Post by Bagasso »

slief wrote:Everything I’ve read indicates that the sodium carbonate or in this case sodium bicarbonate (baking soda) should be added at least a week before the spirit run and the low wines should be aerated during that time.
I don't recall ever reading that you need to aerate when pH treating.

Maybe it's the warm weather where I live but I think aerating for a week will leave you with no alcohol, if there is anything left in the container at all.
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Re: Baking Soda

Post by Nunyo »

Bagasso wrote:
slief wrote:Everything I’ve read indicates that the sodium carbonate or in this case sodium bicarbonate (baking soda) should be added at least a week before the spirit run and the low wines should be aerated during that time.
I don't recall ever reading that you need to aerate when pH treating.

Maybe it's the warm weather where I live but I think aerating for a week will leave you with no alcohol, if there is anything left in the container at all.
Maybe I’m misunderstanding things or your reply. This wasn’t/isn’t for pH treating though adding the sodium carbonate will raise the pH. The addition of the sodium bicarbonate to the low wines (in my case) is to reduce/eliminate esters and or off tastes during the spirit run effectively increasing the hearts and resulting in a more neutral spirit. That said, I have read that adjusting the pH can reduce the esters and off flavors in the 2nd distillation so maybe I am misunderstanding the reason why sodium bicarbonate or sodium carbonate are being used. From what I gathered, it was the reaction of the sodium carbonate that reduces the esters and no so much the pH change. If it’s the increased pH, then I sure can add a lot more because my low wines are still very acidic at around 4 pH. I opted for using bicarbonate because I didn’t want to have to worry about chasing pH numbers and getting to the point of my low wines becoming alkaline where blue distillate and or ammonia become a concern. I have a bunch of sodium carbonate too as it comes in handy in reef applications for raising alkalinity in low pH systems.

The subject of aeration is mentioned throughout the thread when adding Sodium Bicarbonate (as well as sodium carbonate) to the low wines. Not exactly sure what the purpose of the aeration is whether it’s to help mix the solution or if the oxygen helps in the hydrolyization (I think that’s the term) of the esters. Anyhow, just kind of wondering how people are aerating and how much they are doing so between the time the bicarbonate is added and the stripping run. As it sits now, I’m aerating once a day for about 30 minutes.

I also err’d on the side of caution with the amount of bicarbonate I added. The 250 grams was on the low side for 12 gallons of low wines. This has me wondering/contemplating whether I should add more. Especially if it’s better to have a bit higher pH prior to the spirit run.
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Re: Baking Soda

Post by Bagasso »

Nunyo wrote:Maybe I’m misunderstanding things or your reply.
pH treating is just what I call ester hydrolysis using an alkaline.

pH has to be above 7. I'm pretty sure adding bicarb or carbonate to an acidic liquid will just form salts.

I see now the snippet from the parent site that was posted. To me it seems to be talking about doing both but not saying that they are dependent on each other. Like I said, the environment dictates how much airing out you do. I remember airing out a liter for 4 hours with an airpump and losing like 5%ABV.
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Re: Baking Soda

Post by Nunyo »

Bagasso wrote:
Nunyo wrote:Maybe I’m misunderstanding things or your reply.
pH treating is just what I call ester hydrolysis using an alkaline.

pH has to be above 7. I'm pretty sure adding bicarb or carbonate to an acidic liquid will just form salts.

I see now the snippet from the parent site that was posted. To me it seems to be talking about doing both but not saying that they are dependent on each other. Like I said, the environment dictates how much airing out you do. I remember airing out a liter for 4 hours with an airpump and lost like 5%ABV.
Interesting on the loss of ABV. I will just stir it once a day and keep the cover on other than that.

They do talk about using the sodium carbonate or bicarbonate along with salts on the parent site. I passed on the salt and just went with some bicarbonate because I didn’t want to go down the pH rabbit hole figuring the sodium carbonate would raise the pH. Having been involved in reef keeping for many years, I’ve learned that chasing numbers (like pH) can pose issues in that hobby. I have much to learn in this one though. You said above that pH has to be above 7... So you aim for a pH above 7 on your low wines? I thought a pH over 7 will result in the low wines becoming alkaline which should be avoided? Did I misunderstand things? I know that needs to be avoided with the wash because ammonia will be formed but I thought there was also a reason to keep the low wines at a max of 7 pH. I’ve done so much reading here that I’ve probably confused myself. If you aim for a pH around or above 7, what are you using to raise the pH in your low wines if you don’t use sodium carbonate?

By the way, I truly appeciate your input.
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Re: Baking Soda

Post by Bagasso »

Nunyo wrote:Interesting on the loss of ABV.
Yes, but I live in a very dry hot area. Personal mileage may vary.
They do talk about using the sodium carbonate or bicarbonate along with salts on the parent site. I passed on the salt and just went with some bicarbonate because I didn’t want to go down the pH rabbit hole figuring the sodium carbonate would raise the pH.
I think you misunderstood. I wasn't talking about adding salt. The sodium bicarb, carbonate or hydroxide will pair with the acid in the low wines and form salts.
Having been involved in reef keeping for many years, I’ve learned that chasing numbers (like pH) can pose issues in that hobby. I have much to learn in this one though. You said above that pH has to be above 7... So you aim for a pH above 7 on your low wines? I thought a pH over 7 will result in the low wines becoming alkaline which should be avoided? Did I misunderstand things? I know that needs to be avoided with the wash because ammonia will be formed but I thought there was also a reason to keep the low wines at a max of 7 pH. I’ve done so much reading here that I’ve probably confused myself. If you aim for a pH around or above 7, what are you using to raise the pH in your low wines if you don’t use sodium carbonate?

By the way, I truly appeciate your input.
A pH of 7 is neutral and in theory you will not have the ions to carry out the hydrolysis. According to the info on this site:
Ethyl acetate's hydrolysis half-life at 25 deg C and pH 7 is 2 years,...
I usually use sodium hydroxide (lye) and aim for a pH above 11. I then let it sit overnight and drop the pH below 7 before running.

This pdf on hydrolysis has an interesting chart on page 11. Ethyl acetate is CH 3–COO–CH 2–CH 3 so it would seem that it is the line with the second highest peak. The time is in days and you can see how it drops to less than a day at pH 10.
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Re: Baking Soda

Post by Nunyo »

Bagasso wrote:
Nunyo wrote:Interesting on the loss of ABV.
Yes, but I live in a very dry hot area. Personal mileage may vary.
They do talk about using the sodium carbonate or bicarbonate along with salts on the parent site. I passed on the salt and just went with some bicarbonate because I didn’t want to go down the pH rabbit hole figuring the sodium carbonate would raise the pH.
I think you misunderstood. I wasn't talking about adding salt. The sodium bicarb, carbonate or hydroxide will pair with the acid in the low wines and form salts.
Having been involved in reef keeping for many years, I’ve learned that chasing numbers (like pH) can pose issues in that hobby. I have much to learn in this one though. You said above that pH has to be above 7... So you aim for a pH above 7 on your low wines? I thought a pH over 7 will result in the low wines becoming alkaline which should be avoided? Did I misunderstand things? I know that needs to be avoided with the wash because ammonia will be formed but I thought there was also a reason to keep the low wines at a max of 7 pH. I’ve done so much reading here that I’ve probably confused myself. If you aim for a pH around or above 7, what are you using to raise the pH in your low wines if you don’t use sodium carbonate?

By the way, I truly appeciate your input.
A pH of 7 is neutral and in theory you will not have the ions to carry out the hydrolysis. According to the info on this site:
Ethyl acetate's hydrolysis half-life at 25 deg C and pH 7 is 2 years,...
I usually use sodium hydroxide (lye) and aim for a pH above 11. I then let it sit overnight and drop the pH below 7 before running.

This pdf on hydrolysis has an interesting chart on page 11. Ethyl acetate is CH 3–COO–CH 2–CH 3 so it would seem that it is the line with the second highest peak. The time is in days and you can see how it drops to less than a day at pH 10.

Yikes.. Now I have a LOT more reading to do... Thank you very much for the informative response. I will be reading those links your provided and try to wrap my head around that info. School was never my forte nor was reading or studying let alone chemistry but I’d swear, I’ve spent more time reading thread after thread from beginning to end here than I spent reading (timewise) throughout high school. I really appreciate your response and the links. Obviously I have much to learn here. Fortunately, time is on my side and I aim to learn as much as possible here with hopes of being able to contribute down the line while also turning out some decent spirits for my own consumption.

Again, many thanks!
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Re: Baking Soda

Post by Bagasso »

Nunyo wrote:Fortunately, time is on my side and I aim to learn as much as possible here with hopes of being able to contribute down the line while also turning out some decent spirits for my own consumption.
One thing to remember is that none of this is necessary to make a nice drop. The most important things are learning how your rig runs and making cuts. I mean, even with all the tools available, you still have to have a good handle on these two basic things.

Believe me, I have tried because nothing would make me happier than to be able to treat/filter a wash and end up with 10% neutral.
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Re: Baking Soda

Post by Ferrum »

I don't think you should reduce the pH to 7 before running. You basicly split ethyl acetate into vinegar (CH3COOH) and ethanol by having a higher pH, and in turn the vinegar reacts with the base to form sodium acetate (Na+ CH3COO-) which stays in the boiler during running. If you reduce your pH to 7 before running, you will mostly turn the sodium acetate into vinegar, which will be distilled and end up in your product where it will form ethyl acetate again.

Although aluminium is not approved anyway afaik, you should also note that you must never bring a basic solution into contact with aluminium. Especially if you use NaOH you will burn a hole through the aluminium and you will die, which is not good.
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Re: Baking Soda

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Ferrum wrote:I don't think you should reduce the pH to 7 before running. You basicly split ethyl acetate into vinegar (CH3COOH) and ethanol by having a higher pH, and in turn the vinegar reacts with the base to form sodium acetate (Na+ CH3COO-) which stays in the boiler during running. If you reduce your pH to 7 before running, you will mostly turn the sodium acetate into vinegar, which will be distilled and end up in your product where it will form ethyl acetate again.
Did you try it? Once rise the pH of heads or low wines and you will smell the difference. BTW I rise the pH to 11 normally.
Most important is to destroy the ethyl acetate, this is easily solved with high pH.
Second important is to keep the acetic acid in the boiler. You could make an experiment: Pour some vinegar in a jar, add some lime or soda and stir. Then you will recognize that the vinegar smell is gone. No vinegar smell means no vinegar will come over.
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Re: Baking Soda

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der wo wrote:
Ferrum wrote:I don't think you should reduce the pH to 7 before running. You basicly split ethyl acetate into vinegar (CH3COOH) and ethanol by having a higher pH, and in turn the vinegar reacts with the base to form sodium acetate (Na+ CH3COO-) which stays in the boiler during running. If you reduce your pH to 7 before running, you will mostly turn the sodium acetate into vinegar, which will be distilled and end up in your product where it will form ethyl acetate again.
Did you try it? Once rise the pH of heads or low wines and you will smell the difference. BTW I rise the pH to 11 normally.
Most important is to destroy the ethyl acetate, this is easily solved with high pH.
Second important is to keep the acetic acid in the boiler. You could make an experiment: Pour some vinegar in a jar, add some lime or soda and stir. Then you will recognize that the vinegar smell is gone. No vinegar smell means no vinegar will come over.
do you use a copper still? i Have read here that high alkaline wash will cause a blue distillate. personally i have never tried baking soda so i have never seen this happen. ph of 11 seems to me would be very caustic.
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Re: Baking Soda

Post by Bagasso »

HDNB wrote:do you use a copper still? i Have read here that high alkaline wash will cause a blue distillate. personally i have never tried baking soda so i have never seen this happen. ph of 11 seems to me would be very caustic.
That is why you should use something like citric acid to drop the pH down to 7. Contrary to what Ferrum posted, this will not split the sodium acetate back into vinegar. The excess base will react with the new acid to form salts until the solution is neutral (pH 7) and any additional acid will make the solution drop into the acidic range of the pH scale.
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Re: Baking Soda

Post by der wo »

HDNB,

only if you distill a wash, the distillate will be blue. Something with nitrogen. Every wash has nitrogen. A distillate / low wines / feints not, unless you had a puke.
BTW, with baking or washing soda you will never get the pH to 11, because it's not enough soluble, at least at high pH. I use caustic soda. 1g/l is enough for around pH 11. Even with 2g/l (pH 12) there were no issues like rusting copper or stainless or blue distillate. But I don't think there is a difference in taste pH 11 vs pH 12.
PH 11 is probably caustic similar to pH 3.
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Re: Baking Soda

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Bagasso wrote:Contrary to what Ferrum posted, this will not split the sodium acetate back into vinegar. The excess base will react with the new acid to form salts until the solution is neutral (pH 7) and any additional acid will make the solution drop into the acidic range of the pH scale.
Sure? What hinders the acetate-ion to catch the H3O+ of the citric acid and evaporate? As long the salts are water soluble (and sodium citrate is soluble in water) we have ions not salts. And there is no diffeence between a H3O+ of citric or acetic acid. IMO if you neutralize acetic acid, it stops smelling. And if you then add an (non-volatile) acid, it will smell again. But perhaps there are cases, where it's different? Perhaps you could write a bit more about?
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Re: Baking Soda

Post by Ferrum »

At pH 7, no matter what acid or base you used to get there, acetic acid will partly be in acid form, and I believe a good part. at pH 11 it will basicly all be in acetate form. That's why I suggested to keep the pH at 11 while you redistill. If you can keep the vinegar in the boiler otherwise that would also work, but I don;t really see a reason to reduce the pH to 7 before distilling.
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Re: Baking Soda

Post by Bagasso »

Ferrum wrote:At pH 7, no matter what acid or base you used to get there, acetic acid will partly be in acid form, and I believe a good part. at pH 11 it will basicly all be in acetate form. That's why I suggested to keep the pH at 11 while you redistill. If you can keep the vinegar in the boiler otherwise that would also work, but I don;t really see a reason to reduce the pH to 7 before distilling.
At pH 7 there are no free acids or bases. They are in salt form. That is what titration is about. You add an acid or a base until you hit pH 7 and depending on the amount of acid or base that you added to get there it tells you how much there is of the other. Any additional acid or base added will make the reading go above or below 7.

The one reason that I think dropping the pH might be beneficial, just a hunch, is that an acidic solute retains the thiols better. What I'm talking about is my personal experience with pH treated wash, run in stripping mode, which seems to be more "tailsy" than one run at normal pH.
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Re: Baking Soda

Post by Bagasso »

der wo wrote:Sure? What hinders the acetate-ion to catch the H3O+ of the citric acid and evaporate? As long the salts are water soluble (and sodium citrate is soluble in water) we have ions not salts. And there is no diffeence between a H3O+ of citric or acetic acid. IMO if you neutralize acetic acid, it stops smelling. And if you then add an (non-volatile) acid, it will smell again. But perhaps there are cases, where it's different? Perhaps you could write a bit more about?
I think you went way above my kitchen chemistry 101 level.

Is there any reason why the acetate ion would detach from the base to catch the H3O+ of citric acid and, more importantly, why would this, if that is the case, make it (them) more volatile?

Just did a quick experiment: took 1 tablespoon of cooking vinegar (4%) and added 1/2 teaspoon of sodium bicarbonate. Got to pH 7.6 with a lot of the bicarb sinking to the bottom of the container. Let it sit for a little while and when I smelled it had no vinegar smell. Added 1/4 teaspoon of citric acid and the pH dropped to 7.13 and still a bit of bicarb was at the bottom. Added a little more, maybe 1/16 of a teaspoon, and the pH dropped to 6.87. Let it sit a bit more and not much smell to it. There is something there. To me it smells metallic/salty, like alka seltzer, but not like vinegar.
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Re: Baking Soda

Post by der wo »

The acetate-ion is never attached to the base-ion. Except you would boil it down under the solubility point. Acids and salts in solution are always splitted up to ions. Acetic acid is CH3COOH. In solution it is split up into CH3COO- and H+. And for example caustic soda (NaOH) is in solution Na+ and OH-. And their salt sodium acetate (NaCH3COO) is in solution Na+ and CH3COO-. Sodium acetate is very soluble, so "in reality" it doesn't exist unless you boil the solution down. But for example the salt of sulphuric acid and lime is very insoluble. So if you mix those substances in water, you get calcium sulfate, it will settle out.

So if you have mixed vinegar with bicarb, the acetate ion is still there, but alone it cannot evaporate. It needs a H+ to form the acid again and then it can evaporate. Where the H+ comes from isn't important. Perhaps citric acid, perhaps sulphuric acid, it doesn't matter.

But why did the second part of your experiment fail? Because a pH slightly under 7 isn't enough to get vinegar in smellable amounts. Normal cooking vinegar has something like pH 2.5. I think you added way too much bicarb. Before adding citric acid you should have discarded the bicarb sediment or the citric acid is sucked up by the excess bicarb. And citric acid is not really strong. But probably when discarding the sediment, it should work to lower the pH to 3-4. I did this experiment with sulphuric instead of citric acid.
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