Apple Cider Vinegar

[AK Qtifan]

Hi all,

Thanks for this opportunity and great forum.

I took on a project with a group of friends to produce 50,000 litres of apple vinegar naturally, out of belief in its health benefits. We are all novices and upon seeing how it's traditionally done in a farm we thought to give it a go.

We pressed about 77 tonnes of apples (mainly Spartan and Ida Red). 

We filled the juice in brand new IBCs and intend to ferment the juice in the same IBCs to cut costs.

We have read both recommended books: Craft Cider Making by Andrew Lea and Real Cidermaking by Michael Pooley and John Lomax. We are unsure about the following issues since the section on vinegar making is limited in both books:

1. Since the ultimate aim is to produce natural vinegar, should we ferment directly into vinegar as in, not wait till we ferment all sugar into alcohol then transfer alcohol into acidity? Can both fermentations happen simultaneously if we introduce air? 

2. Please note we do not plan to add any yeast. At which stage should we add the vinegar mother? Right from the start or once alcohol fermentation is say half way through?

2. We plan to inject air into the IBCs to speed-up the process using an aerator (the types used for fish ponds or waste industry like side channel blowers or regenerative blowers). At which stage is it recommended to do so? Right from the start or once we get full alcohol fermentation?

3. Current juice sugar is about %11. Is it realistic to expect a vinegar acidity of %6 by the end of it? And if so how can we dilute it to the recommended %5, bearing in mind the juice is certified organic, and we wish to maintain that accreditation for the vinegar?

4. Do you recommend any books or specialist resources on the subject? Any courses that you may recommend?

5. Would you recommend the use of industrial vinegar making machines to the method described above? Some machines produce vinegar within a day with the addition of lab-made bacteria and forced aeration. But they tend to be costly and not sure if it's feasible to handle 50,000 litres?

6. Lastly, once vinegar is made, it is said to leave it to age for at least 5 months. Is that necessary? And why?

Many thanks indeed.

Abdul

[Andrew Lea]

On 19/11/2014 07:41, AK Qtifan wrote:

>
> 1. Since the ultimate aim is to produce natural vinegar, should we
> ferment directly into vinegar as in, not wait till we ferment all
> sugar into alcohol then transfer alcohol into acidity? Can both
> fermentations happen simultaneously if we introduce air?

No. It is a two step process. Anaerobic (yeast) followed by aerobic
(acetobacter). You can't mix them. They have to be sequential.

>
> 2. Please note we do not plan to add any yeast. At which stage should
> we add the vinegar mother? Right from the start or once alcohol
> fermentation is say half way through?

Once the yeast fermentation is entirely finished. You should then rack
the cider off the yeast before trying to acetify it.

>
> 2. We plan to inject air into the IBCs to speed-up the process using
> an aerator (the types used for fish ponds or waste industry like
> side channel blowers or regenerative blowers). At which stage is it
> recommended to do so? Right from the start or once we get full
> alcohol fermentation?

Once the yeast fermentation is entirely finished.

Be aware that once you
start to pump / sparge air into the bulk, the mother (Acetobacter
xylinum) will mutate into a single cell form (Acetobacter aceti). It
will become entirely dependent on the forced air supply and will
probably die if it doesn't get it. Acetobacter are obligate aerobes. The
'mother' is a mat they make to keep them in contact with air. The
precise technology of forced aeration in submerged vinegar acetators is
critical to success. You cannot really mix the static Orleans surface
process with a forced aeration (submerged) process.

Acetification is also exothermic and in a large forced aerator with no
temperature control the bacteria can also overheat and die.

>
> 3. Current juice sugar is about %11. Is it realistic to expect a
> vinegar acidity of %6 by the end of it? And if so how can we dilute
> it to the recommended %5, bearing in mind the juice is certified
> organic, and we wish to maintain that accreditation for the vinegar?

Presumably you must use organic certified water ;-)

>
> 4. Do you recommend any books or specialist resources on the
> subject? Any courses that you may recommend?

http://link.springer.com/chapter/10.1007/978-1-4684-8225-6_13

http://link.springer.com/chapter/10.1007/978-1-4613-0309-1_1

>
> 5. Would you recommend the use of industrial vinegar making machines
> to the method described above? Some machines produce vinegar within
> a day with the addition of lab-made bacteria and forced aeration.

For 50,000 litres, yes. The bacteria are not 'lab-made'. They are
simply selected from wild Acetobacter strains.

> 6. Lastly, once vinegar is made, it is said to leave it to age for at
> least 5 months. Is that necessary? And why?

Improved flavour. Sedimentation of polyphenol hazes. Those are two reasons.

Andrew

--
near Oxford, UK
Wittenham Hill Cider Portal
www.cider.org.uk

[Lewis]

Fascinating topic. I too have been making CV but on a much smaller scale. I currently have a 235l container full, the bulk of which is 3 years old and the youngest addition to it is a year old. The mother is submerged and looks and feels like a cross between an anaconda and a crocodile. I'm not sure what to do next. Should I simply draw it off and bottle it? Will the mother automatically regrow in the bottle if I don't actually take bits off it? Does anybody filter theirs? All comments welcomed. Will check Andrew's link for more info. Cheers. Lewis

[Andrew Lea]

On 19/11/2014 17:13, Lewis wrote:

> Fascinating topic. I too have been making CV ...

> I'm not sure what to do next. Should I simply draw it off and
> bottle it?

Have you analysed the acid level? It needs to be a minimum of 5% to be
called vinegar.

> Will the mother automatically regrow in the bottle if I don't actually take bits off it? Does anybody filter theirs?

Mother will regrow in bottle if (a) there is unconverted alcohol and /
or (b) access to air eg through a faulty cap. You can stop this by
pasteurising or using SO2. Filtration of cider vinegar is not easy on a
small scale and you might like to fine it first. The two-part finings
work well.

Cider vinegar sometimes goes hazy in the bottle even if filtered, due to
tannin polymerisation. SO2 will stop this. If you are only using it
yourself, it hardly matters. If you are selling it, some people get
around that by putting a label on the bottle drawing attention to its
'natural' qualities and turning a drawback into a strength!

[Lewis Scott]

Thanks Andrew. Would you test the acidity using a TA kit as you do in cider?

On Wednesday, November 19, 2014 7:48:26 AM UTC, abed140 wrote:

[Andrew Lea]

On 20/11/2014 15:21, Lewis Scott wrote:
> Thanks Andrew. Would you test the acidity using a TA kit as you do in cider?

See http://cider.org.uk/acid_titration.html

You have to dilute the vinegar because it's round about 10x more acid
than cider.

[mann bataan]

hi all

     can i get more information about apple cider vinegar. i tried to make apple cider vinegar in food grade plastic tank by slow method but after once or twice the rate of growth is getting slow and overtime it stops now. can anybody help me out please?

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[vince wakefield]

What % acid are you currently at and what % acl did you start with?

 

Vince

 

From: cider-w...@googlegroups.com [mailto:cider-w...@googlegroups.com] On Behalf Of mann bataan
Sent: 07 December 2014 12:05 PM
To: cider-w...@googlegroups.com
Subject: Re: [Cider Workshop] Re: Apple Cider Vinegar

 

hi all

     can i get more information about apple cider vinegar. i tried to make apple cider vinegar in food grade plastic tank by slow method but after once or twice the rate of growth is getting slow and overtime it stops now. can anybody help me out please?

On Thu, Nov 20, 2014 at 8:54 PM, Andrew Lea <y...@cider.f9.co.uk> wrote:

On 20/11/2014 15:21, Lewis Scott wrote:

Thanks Andrew. Would you test the acidity using a TA kit as you do in cider?

See http://cider.org.uk/acid_titration.html

You have to dilute the vinegar because it's round about 10x more acid than cider.

Andrew

--
near Oxford, UK
Wittenham Hill Cider Portal
www.cider.org.uk

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[Andrew Lea]

If things used to work well but don't any more, perhaps the 'mother' has become infected with a bacteriophage (effectively a virus that preys on bacteria). You might need to sterilise everything and start with a brand new culture. That's just one of many possibilities. 

Have you read all the vinegar literature which I cited previously in the vinegar thread?

Andrew

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[mann bataan]

2 tanks capacity of 500 litres are stuck at 3 % acidity and 2-3 are at abt 2% acidity and andrew sir i have read literature but still if you have something more to read i will read all

[mann bataan]

and stuck at 3 % acidity more than 1 month

[Andrew Lea]

What % alcohol did you start with? What was the starting gravity of the original cider juice? 

Andrew

Sent from my iPhone

[mann bataan]

specific gravity was almost 1045 and alcohol of the cider was almost 7 to 7.5% v/v

[Andrew Lea]

Oh and what is the temperature where you are?

Andrew

Sent from my iPhone

[mann bataan]

temperature is about 10 min and 17 day time but for temperature i am using room heaters to raise temp abt 25-30 degree 

[Claude Jolicoeur]

Le dimanche 7 décembre 2014 10:01:42 UTC-5, manoj battaan a écrit :

specific gravity was almost 1045 and alcohol of the cider was almost 7 to 7.5% v/v

Potential alcohol of a must at SG 1045 is less than 6% ABV.... Unless you added sugar, this isn't possible.

[mann bataan]

some amount of sugar is also used and initial specific gravity of mixture was about 1050-1055. 

--

[vince wakefield]

Can I just clear something up,

 

Are you still on the making cider stage ?

 

Your 1^st post was only in November and at that stage it looked like you had just pressed the apples

 

If so we are talking about a stuck fermentation which is a very different thing.

 

Vince

 

From: cider-w...@googlegroups.com [mailto:cider-w...@googlegroups.com] On Behalf Of mann bataan
Sent: 07 December 2014 3:24 PM
To: cider-w...@googlegroups.com
Subject: Re: [Cider Workshop] Re: Apple Cider Vinegar

 

some amount of sugar is also used and initial specific gravity of mixture was about 1050-1055. 

[mann bataan]

no vince i have made cider successfully then then i have made cider vinegar upto 6 % acidity 2-3 times successfully but now its getting trouble ans stuck at about 3% acidity more than 1 month even more time

[mann bataan]

i heard there is any fast process of cider vinegar by some generators? it is true?

[mann bataan]

i know the basics that it need more aeration and temperature should be about 25-30 degree.

but i dont know how to make a generator?

[vince wakefield]

You may find the data on this site of use

http://cetotec.com/

[Andrew Lea]

On 07/12/2014 15:36, mann bataan wrote:
> i know the basics that it need more aeration and temperature should be
> about 25-30 degree.
> but i dont know how to make a generator?

Google is your friend. See here
http://naldc.nal.usda.gov/download/ORC00000397/PDF (12 MB download). Fig
4 shows a classic beechwood 'generator'. Fig 3 shows a 'rolling
generator' which is much simpler. Modern 'acetators' use forced aeration
with no solid supports for the bacteria but that is another big step of
complexity and cost.

These are also described in the references i cited before

http://link.springer.com/chapter/10.1007/978-1-4684-8225-6_13

http://link.springer.com/chapter/10.1007/978-1-4613-0309-1_1

In your present case I wonder if you might need extra nutrients if the
acetic fermentation has 'stuck'? Maybe you should try 120 ppm of
ammonium phosphate. I presume the air supply is unimpeded? And you must
keep the temperature up as you say. Otherwise you may be suffering from
a phage as I said before.

[AK Qtifan]

Dear Andrew and the great members,

I have read both Andrew's book and bought and read his chapter on vinegar from the recommended links. In fact I bought that entire book which I believe is a must to have for any apple produce processor. 

I still however have the following queries:

1. Is getting the PH level right necessary for vinegar production? Should we bother or is it luxury?    

2. I plan to leave my apple juice to ferment naturally in IBCs for 3 weeks without adding any yeast. I have created a hole in the lids and wielded an airlock valve. If all goes well and I end up transforming all sugar into alcohol I plan to create another hole in the lids (to allow a tube to go to the bottom of the IBC) and introduce slow forced aeration into the IBCs (using an aerator used for fish ponds or the likes) to speed up the acetification without the need to add bacteria. I understand the bacteria might die in minutes if aeration stops and I understand the overheating issue (is there a particular volume of air that we can inject on a much slower levels that does not overheat everything that bad but at the same time maintain enough O2 for bacteria to work slowly and produce vinegar over a month as opposed to over a day or two?). Providing we set things right and all goes to plan. What are the pros and cons of the plan above as opposed to using the industrial submerged acetification machines? The idea is to cut costs down and keep it as close to a traditional method?

3. If we are to thermostat-control it, what is the ideal temperature for both fermentations (cider and then vinegar) the wild slow way, i.e. If we are to leave Mother Nature to do its work with minimal intervention on our part, hoping for the best?! (If we are not to introduce forced aeration)

4. Is adding nutrients at all necessary for vinegar production if we start with a %100 apple juice, organic at that?

5. Why should the cider be allowed to age for one month before being used as a feedstock for vinegar?

6. Is A. Xylinum and polyphenol not good for health?! I know producers in the UK make various chutneys from A. Xylinum and claim that it has beneficial bacteria and important enzymes for humans. I also read polyphenols to be healthy and antioxidant (like here http://m.ajcn.nutrition.org/content/81/1/215S.full )

7. Are we filtering/ removing from vinegar 'the mother', pectins, polyphenol etc for mere aesthetic effects (i.e. Looks) ignoring the contribution of these elements to human health? On the other hand we certainly don't want to leave junk or waste behind in the final product. Where do we draw the line (between the ultra sterile folks and those ultra raw so to speak?!)

Apologies for the long list of questions. It took me days to put together!

Sincerely,

Abdul

[Andrew Lea]

On 08/12/2014 02:04, AK Qtifan wrote:

>
> I still however have the following queries:
>
> 1. Is getting the PH level right necessary for vinegar production?
> Should we bother or is it luxury?

One the one hand I doubt that it matters much about pH control of the
alcoholic fermentation if it's to be turned into vinegar. On the other
hand if it's too high (say > 3.8) it may encourage the growth of
unwanted lactic acid bacteria? So maybe stick to normal recommendations
(i.e. pH < 3.8).

>
> 2. I plan to leave my apple juice to ferment naturally in IBCs for 3
> weeks without adding any yeast.

3 weeks may not be long enough with wild yeast. Monitor the SG and let
it take as long as it takes.

> tube to go to the bottom of the IBC) and introduce slow forced aeration
> into the IBCs (using an aerator used for fish ponds or the likes) to

> speed up the acetification without the need to add bacteria.......

> What are the pros and cons of the plan above as opposed to using the industrial
> submerged acetification machines?

Unless you are a proper (bio)chemical engineer and can do all the right
calculations about gas exchange, O2 demand, heat production etc, then
you are 'flying by the seat of your pants'. The design and perfection of
the Frings and Greenshields acetators was not by accident (though I
think the latter is no longer in production). There was a lot of
planning, a lot of calculation and a lot of empirical tweaking to get
them to a commercially working stage. I doubt that anyone here can help
you with that. In any case it is proprietary knowledge and something of
a "trade secret".

>
> 3. If we are to thermostat-control it, what is the ideal temperature for
> both fermentations (cider and then vinegar) the wild slow way, i.e. If
> we are to leave Mother Nature to do its work with minimal intervention
> on our part, hoping for the best?! (If we are not to introduce forced

> aeration).

You could probably thermostat the alcoholic fermentation as high as 20C.
The vinegar conversion could / should be warmer up to 30C? But don't let
it overheat ;-)

>
> 4. Is adding nutrients at all necessary for vinegar production if we
> start with a %100 apple juice, organic at that?

Not needed for the slow Orleans process, or for a beechwood 'generator'.
Probably necessary for the submerged culture acetators because the
biochemical demand is so stressful and fast conversion is the goal.

>
> 5. Why should the cider be allowed to age for one month before being
> used as a feedstock for vinegar?

To be sure the yeast has totally stopped working and to change from a
'reducing' environment to an 'oxidising' one.

>
> 6. Is A. Xylinum and polyphenol not good for health?!

No comment. You can believe whatever you want to.

[AK Qtifan]

Dear Andrew,

Thanks for your reply and valuable feedback.

I will write my points/ questions below yours:

>> tube to go to the bottom of the IBC) and introduce slow forced aeration
>> into the IBCs (using an aerator used for fish ponds or the likes) to
>> speed up the acetification without the need to add bacteria.......
>> What are the pros and cons of the plan above as opposed to using the industrial
>> submerged acetification machines?
>
> Unless you are a proper (bio)chemical engineer and can do all the right calculations about gas exchange, O2 demand, heat production etc, then you are 'flying by the seat of your pants'. The design and perfection of the Frings and Greenshields acetators was not by accident (though I think the latter is no longer in production). There was a lot of planning, a lot of calculation and a lot of empirical tweaking to get them to a commercially working stage. I doubt that anyone here can help you with that. In any case it is proprietary knowledge and something of a "trade secret".
>

The reason why we thought of the make-shift method is because a farmer we know in South East England produces vinegar successfully this way which I have personally saw and sampled. He does not have any biochemical background. He merely used the method to speed up his traditional production a little. But I do take all your points on board. We got at least 2 months to decide which way to go. Or we might test run few batches on the side for experiment.

For 60,000 litres of vinegar production, what is the capacity of the submerged acetator that you would recommend? Any low-budget ones that you may point out to us to buy? It's primarily going to be used seasonally.

>>
>> 3. If we are to thermostat-control it, what is the ideal temperature for
>> both fermentations (cider and then vinegar) the wild slow way, i.e. If
>> we are to leave Mother Nature to do its work with minimal intervention
>> on our part, hoping for the best?! (If we are not to introduce forced
>> aeration).
>
> You could probably thermostat the alcoholic fermentation as high as 20C. The vinegar conversion could / should be warmer up to 30C? But don't let it overheat ;-)

We are working on raising the heat now.

>>
>>
>> 5. Why should the cider be allowed to age for one month before being
>> used as a feedstock for vinegar?
>
> To be sure the yeast has totally stopped working and to change from a 'reducing' environment to an 'oxidising' one.
>>
>> 6. Is A. Xylinum and polyphenol not good for health?!
>
> No comment. You can believe whatever you want to.
>
> Andrew
>
>
> --
> near Oxford, UK
> Wittenham Hill Cider Portal
> www.cider.org.uk
>

[AK Qtifan]

Sorry my previous email was sent accidentally before completion...
>>

Are there any specialised courses that any one offers for vinegar production? Or a consultation service you may know?

>> 6. Is A. Xylinum and polyphenol not good for health?!
>
> No comment. You can believe whatever you want to.

I did not mean to create a stir there Andrew... lol (I hope I was not perceived as such at least). I was merely trying to bring up health claims, ardently being supported and challenged at the same time on the Internet (just google 'Apple Cider Vinegar for health' and see for yourself). I thought it's relevant to this forum and was hoping for some scholarly or personal feedback as to where the valid claims might be.

Abdul

>
>
> --
> near Oxford, UK
> Wittenham Hill Cider Portal
> www.cider.org.uk
>

[Andrew Lea]

On 08/12/2014 17:54, AK Qtifan wrote:

> The reason why we thought of the make-shift method is because a
> farmer we know in South East England produces vinegar successfully
> this way which I have personally saw and sampled. He does not have
> any biochemical background.

Well of course you might strike it lucky first time by being purely
empirical ;-) But for the volumes you are contemplating, it seems a
huge gamble if you have never made any cider or vinegar before.

>
> For 60,000 litres of vinegar production, what is the capacity of the
> submerged acetator that you would recommend? Any low-budget ones that
> you may point out to us to buy? It's primarily going to be used
> seasonally.
>

No good asking me! I'm not a vinegar technologist. Talk to specialists
like Frings
http://www.frings.com/ACETATORS-Fermenters.52+M52087573ab0.0.html
http://www.frings.com/fileadmin/assets/Download_Essig/FRINGS_VINEGAR_2009.pdf
or Cetotec http://www.cetotec.com or Labu
http://www.labu.at/en/direct-marketing/fruit-processing/vinegar-production/

> Are there any specialised courses that any one offers for vinegar production? Or a consultation service you may know?

Nothing in the UK AFAIK. You could try these people in Austria, though I
know nothing about them http://www.essig.at/en/consulting/

[Andrew Lea]

On 08/12/2014 17:54, AK Qtifan wrote:

> Dear Andrew,
>
[Acetator] It's primarily going to be used seasonally.

Why? Have you thought that through? If you have a generator or an
acetator and it's thermostatted, you can make vinegar all the year round
on a short cycle in smaller volumes from bulk stored cider. That's the
way it's normally done, and cuts down on capital costs.

[David Llewellyn]

Abdul,
As Andrew has said, You can try http://www.essig.at/en/consulting/
The man you will talk to is Andreas Fischerauer, whom I know personally. He
speaks good English, and he travels around the world a lot, doing
consultancy and advisory work. He has a lot of clients in the Arab region! I
think with that kind of production volume you will not be able to achieve it
without investment in good equipment. Andreas will advise you about
everything you need to know!

David Llewellyn
Tel: + 353 87 2843879
www.llewellynsorchard.ie
(previously 'fruitandvine.com')

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[Andrew Lea]

If you want to 'go it alone' you might like to follow up the patents
cited below to understand what sort of technology has been used:

"Vinegar production is an important fermentation process in which
vinegar is produced from dilute aqueous alcoholic solutions such as
charging wort. Vinegar is made by a variety of processes and the most
widely used modern apparatus for the production of vinegar is the
Fring's generator (British Pat. No. 731,804 and No. 1,101,560) which is
a semi-continuously operated, vortex-stirred tank giving volumetric
efficiencies of up to 0.5 (the volumetric efficiency is the ratio
between the volume produced daily and the effective volume of the
fermentation vessel) with 96 to 98% conversion of ethanol into acetic
acid, thus permitting performances of up to 0.48 to 0.49 (the
performance is obtained by multiplying the volumetric efficiency and the
percentage of conversion divided by a factor 100). This system has still
not entirely replaced the much older and far less efficient, so-called
"Quick" process (cf. British Pat. No. 781,584), involving the continuous
recirculation and sparging over birch twigs and other fillings in large
wooden vats.

A recent development in the production of vinegar is that of
Greenshields (cf. British Pat. No. 1,263,059), using an elongated vessel
similar to that of the Fring's generator, but using an upwardly moving
fermentation medium, whereas the Fring's process uses a downward stream.
According to the Greenshields process, volumetric efficiencies of up to
about 1.0 are achieved, with up to 88% conversion, thus permitting a
performance of about 0.88.

In the vinegar process special kinds of bacteria are used, generally
Acetobacter species, and for a high efficiency it is advantageous that
the bacteria are well suspended in the culture medium. On the other
hand, it is preferable that the bacteria settle quickly to achieve high
volumetric efficiencies without the risk that the bacteria, or a
substantial part thereof, are taken along with the final product, in
which they remain suspended. Therefore, it is important to use elongated
vessels, as indicated in British Pat. No. 1,263,059. Loss of bacteria
can also be reduced by including a separate sedimentation vessel having
a larger cross-section than the fermentation vessel to achieve
sedimentation of the bacteria. Thus, an important limitation of the
volumetric efficiency of known processes is the limited capability of
the bacteria to settle out before removal of the final product."