Suggestions for keeving after two years of failures

[Jan]

Despite two years of failures I am again convinced to clear the cider by keeving it. Knowing that doing it the same way as in the past will not work, I decided to sum it up and ask masters for recommendations.

The only positive thing is that I always achieved the same result, which is a full cask of yellow jelly that is partially breaking down in March, while the temperature goes higher and fermentation is getting more vigorous. There are about two inches thick layer of a clear must in the middle (in about 50cm high cask). Once the fermentation reaches its peak about 50% of the jelly turns into liquid again, the rest remains jelly-ish and must be thrown away.

SG is above 1.055, Keeving temperature is between 8-10°C, pH is 3,3

1. I am following the process as described in the Klercidre kit manual

2. Do not add Yeast

3. Using 35l demijohns filled to 2/3 so there is enough space for the hat.

4. Do sulphite, 30ppm (half of the proposed amount) 

My assumptions are

1. There is already enough pectin in the must, thus adding PME will be too much – Add or not add?

2. Fermentation starts slowly - do not suplhite, add yeast?

3. Too low temperature

 

Any ideas?

 

Thank you

Jan

[Claude Jolicoeur]

I think you need to give more information on what you are doing in order to be able to have a better idea of what is wrong.
I assume you start the keeving process in November. What sort of apples do you use? Your pH are low, hence quite acidic apples.
With such low pH, for sure I would not add any sulfite. I can't say for sure however that this is the cause of your failures. But certainly this is the first parameter I would change.

See below about your assumptions

Le samedi 23 novembre 2013 14:22:01 UTC-5, Jan a écrit :

Despite two years of failures I am again convinced to clear the cider by keeving it. Knowing that doing it the same way as in the past will not work, I decided to sum it up and ask masters for recommendations.

SG is above 1.055, Keeving temperature is between 8-10°C, pH is 3,3

1. I am following the process as described in the Klercidre kit manual

2. Do not add Yeast

3. Using 35l demijohns filled to 2/3 so there is enough space for the hat.

4. Do sulphite, 30ppm (half of the proposed amount) 

My assumptions are

1. There is already enough pectin in the must, thus adding PME will be too much – Add or not add?

You definitely should add PME.

1. Fermentation starts slowly - do not suplhite, add yeast?

What is your SG like in March? Has the juice fermented by then? If not, this is possibly the problem.

1. Too low temperature

Your temperatures are OK.

Claude

[Andrew Lea]

On 23/11/2013 21:30, Claude Jolicoeur wrote:
> I think you need to give more information on what you are doing in order
> to be able to have a better idea of what is wrong.
> I assume you start the keeving process in November. What sort of apples
> do you use? Your pH are low, hence quite acidic apples.
> With such low pH, for sure I would not add any sulfite. I can't say for
> sure however that this is the cause of your failures. But certainly this
> is the first parameter I would change.

I agree with Claude. pH 3.3 is quite low to be trying keeving. I would
leave out the sulphite and add it after keeving instead. You need to
encourage those apiculate yeasts to get the cap to rise long before it
breaks up. But would not be wise to add a commercial yeast which will be
far too vigorous.

You should of course still add the enzyme, because that is essential to
the pectin demethylation process. The fact you get such a dense gel may
possibly indicate too much calcium, so you might cut back a bit on that.
Are you growing your apples on alkaline soil?

Demijohns are not ideal for keeving because of the narrowed necks and
poor access. A straight sided vessel with a bottom tap is best.
Presumably you are not keeping any sort of positive pressure in the
demijohns during keeving i.e. no airlocks?

Andrew


--
Wittenham Hill Cider Portal
www.cider.org.uk

[Jan]

I believe I need to do a drastic change, otherwise will end up in the same situation. Unfortunately the amount of must I have will allow only a single try.

- I know demijohns are not the best, unfortunately there is nothing else I can use. This is the reason why I do not fill them up, and keep some extra space in there. No airlock was used at the beginning (before it become jelly)

- SG in March was low about 1.005, another batch which was having a bit thicker layer of clear cider was having SG of 1.010, I was hoping to be partially successful in reducing the nutrients, but after cleaning the remaining jelly and racking it off, it fully fermented all remaining sugar.

In KlerCidre kit, they do suggest 0.427l of CaCl2 per 500l -700l of must, for the lower boundary it is 0.8ml per liter. In the past I was using 1ml/1l. I have no evidence about the soil, as I am buying the apples from a farmer, and it is a mixture of various apples. Last year I did use apples from my friend's garden and the result was the same.

On the day of pressing I was adding SO2, two hours later PME and for one batch 12h later and for another 24h later the CaCl2, there was a small difference between the batches (the later was having the clear cider layer a bit thinner)  . A 1l test batch turned at 22°C to a jelly within 24hrs. Demijohns at 10°C required for full jelly about a week.

1) Why do you think pH 3.3 is too low? To reduce the acidity, can I add some water and check the suger to have SG above 1.055? What is the pH target.

2) I did press the must yesterday in the mornig (24hrs ago). I am not going to use SO2 this time, should I wait to see some yeast activity, or add the PME and CaCl2 now?

3) I still think I do have about 24hrs before it is too late (8°C), can I try a test on 1l? How much of CaCl2 you would recommend to use 0.5ml / liter?

Thank you

Jan

[Claude Jolicoeur]

Le dimanche 24 novembre 2013 08:18:22 UTC-5, Jan a écrit :

I believe I need to do a drastic change, otherwise will end up in the same situation. Unfortunately the amount of must I have will allow only a single try.

If you have only one single try to do, I would try without sulfite.
 

- I know demijohns are not the best, unfortunately there is nothing else I can use.

Plastic pails are not hard to procure and work very well - they are available in many sizes, the largest I have are 30 liters.

1) Why do you think pH 3.3 is too low? To reduce the acidity, can I add some water and check the suger to have SG above 1.055? What is the pH target.

I have had successful keeves at low pH, hence I don't think this is too low for the keeve, but it is too low to add sulfite.
 

2) I did press the must yesterday in the mornig (24hrs ago). I am not going to use SO2 this time, should I wait to see some yeast activity, or add the PME and CaCl2 now?

Add PME as soon as the juice flows out of the press, calcium 2 days later should be fine.
 

3) I still think I do have about 24hrs before it is too late (8°C), can I try a test on 1l? How much of CaCl2 you would recommend to use 0.5ml / liter?

I don't know which concentration they use for CaCl2 in the Klercidre kit, hence impossible to give recommendations on this.

Claude

[Andrew Lea]

On 24/11/2013 13:18, Jan wrote:
>
>
> 1) Why do you think pH 3.3 is too low?

Two reasons. (1) the PME activity decreases as the pH drops and (2) the
perceived acidity in the final cider will be quite high for a keeved
style. If you can blend apples then pH 3.5 might be a good target value.
But don't add water. Live with what you've got.

In your case the PME seems to be active at pH 3.3 since you appear to be
getting good gel formation. Your problem seems to be you are not getting
enough yeast activity. Hence don't add SO2.

> 2) I did press the must yesterday in the mornig (24hrs ago). I am not
> going to use SO2 this time, should I wait to see some yeast activity, or
> add the PME and CaCl2 now?

You should add the PME as soon as the juice is pressed, and the CaCl2
afterwards. Do not wait until you see yeast activity - by then it will
be too late.

> 3) I still think I do have about 24hrs before it is too late (8�C), can
> I try a test on 1l? How much of CaCl2 you would recommend to use 0.5ml /
> liter?

I don't understand. You seem to be confusing testing with the real
thing? If you want to test, do a test. I never do.

[Jan]

Andrew, you were suggesting to reduce the amount of CaCl2. I am trying to get the idea how much is a bit. What I wanted to say is that the amount of the calcium used turns the must into jelly within 24hours (at room temperature). So what should be the result if I lower the amount of calcium? There will be no fermentation going on is such short time.

Thank you

Jan

 

> 3) I still think I do have about 24hrs before it is too late (8�C), can

[Andrew Lea]

On 24/11/2013 22:20, Jan wrote:
> Andrew, you were suggesting to reduce the amount of CaCl2. I am trying
> to get the idea how much is a bit. What I wanted to say is that the
> amount of the calcium used turns the must into jelly within 24hours (at
> room temperature). So what should be the result if I lower the amount of
> calcium?

I'm not sure from your questions that you really understand the
mechanism of the keeving process. Have you looked at the keeving page on
my website http://www.cider.org.uk/keeving.html and also the download
link http://www.cider.org.uk/keeving.pdf that I give there? This shows
how the PME demethylates the pectin to form polygalacturonic acid which
then complexes and crosslinks with calcium to give a gel. The gel then
further complexes nutrients and yeast, and gas production from the yeast
then helps to lift the cap. When you remove the juice from the cap you
should then have a slowly fermenting nutrient poor juice. That is what
keeving is all about.

The strength of the gel depends upon the amount of cross linking and
hence upon the amount of calcium present. Hence my _hypothesis_ is that
if you get a very heavy set and immobile gel which totally fills your
container within a day, you might do better with a looser gel and hence
you need to add a bit less calcium. I can't tell you how much less, but
as a start I'd say maybe 3/4 or 1/2 of what you normally add. I don't
know this will work - it's just a suggestion. Are you sure you don't
have the volume to run some small scale trials under different conditions?

Can I yet again paraphrase what I said a couple of days ago ... "Anyone
trying the art of keeving should realise they are experimentalists and
are pushing the boat out. It is not a recipe based operation (do this,
do that and do the next thing and you will get a perfect result!). There
are lots of uncontrolled variables and until you have built up some
experience you won't know what works best for you. I say all this
because I don't want people to be disappointed or to moan to me because
"it didn't do what it says on the tin"!"

[Claude Jolicoeur]

Andrew Lea wrote:

the perceived acidity in the final cider will be quite high for a keeved
style.

Yes and no...
True, with low pH / high TA, the so called keeved style of English or French ciders don't match with the end result. However, my opinion is that a successfully keeved cider is even more valuable on a more acidic must, because the residual sugar will then balance the excess acidity and make very nice cider.
This is a bit the principle of ice cider, where the TA is extremely high (in the order of 12 to 15 g/L malic), but since there is also a very high residual sugar of the order of 130 g/L (final SG over 1.060), acidity and sugar balance well to give a very tasty end product...
Claude

[Jan]

I am afraid I lost another year. Although this time the gel is not so hard as a gelatin, it is thick enough to capture CO2 bubbles. The change to the process wa ¾ of CaCl2 compared to what they suggest in the Klercidre kit and no sulfite.

 

Assuming the problem is in the amount of calcium used, my question would be how to find the right amount. I guess there is no option, to add the calcium multiple times, so I will need to have many small batches to see some difference. Or do you suggest any other procedure?

[Claude Jolicoeur]

I am not too sure what you mean here.
You have a gel, but it is not rising? Do you have any signs of a start of fermentation? The gel may take as long as 2 weeks to form and compact itself. Maybe it would be worth it not to throw the towel too soon. (Sorry, this is translation of a French expression, "lancer la serviette" which mean to abandon- dunno if the same in English)
Claude

[Jan]

After checking these pictures posted by Chris http://cidersupply.com/Page%20-%20Good-Bad-Ugly.html,  I can tell that my problem was identical to the second picture from the right in the first row. “Too much natural pectin…”

 

Our conclusion in this thread was too much of CaCl2, so what is correct?

[Andrew Lea]

On 29/11/2013 16:49, Jan wrote:
> After checking these pictures posted by Chris

> _http://cidersupply.com/Page%20-%20Good-Bad-Ugly.html_,I can tell that

> my problem was identical to the second picture from the right in the

> first row. �Too much natural pectin��

>
> Our conclusion in this thread was too much of CaCl2, so what is correct?

Well they could both be correct, since both are needed to form a gel!
Step 1 is to form a gel, which you have done. Step 2 is to wait to allow
yeast growth to let it rise. This may take a couple of weeks. How long
have you waited so far? In the past you added sulphite which we thought
may have inhibited it. This year you have not used sulphite so things
should happen quicker.

Just to be clear, does your current gel now look like the picture in
Chris' gallery, or is that what it looked like in previous years?

Which country are you in, what sort of apples are you using, and are you
macerating the pulp before pressing to liberate more pectin?

[Jan]

The second picture from the right first row is what I did end up with in the last two years.

This year (one week after addition of CaCl2) it looks more like the second from the left on the second row, just that the clear juice layer is about 0.5cm high. The gel was formed after 24hours after addition of CaCl2. The layer of clear juice is slowly getting thicker. I did warm it up to 12C. Unfortunately mould spots are showing up.
 
My apples are grown in the Czech Republic.
Yes the pulp was macerated for about 18hrs

[Andrew Lea]

On 29/11/2013 17:22, Jan wrote:
>
> This year (one week after addition of CaCl2) it looks more like the
> second from the left on the second row, just that the clear juice layer
> is about 0.5cm high. The gel was formed after 24hours after addition of
> CaCl2. The layer of clear juice is slowly getting thicker. I did warm it
> up to 12C. Unfortunately mould spots are showing up.

If you had an open straight-sided vessel you could easily take the mould
spots off. That is one advantage of it. Mould spots usually attach to
small pieces of floating apple pulp.

The gel is now sinking, right? Is there any sign of fermentation at all?
(I think 12C is rather warm but if you are worried about trying to
encourage fermentation I see why you would maybe do that).

>
> My apples are grown in the Czech Republic.

> Yes the pulp was macerated for about 18hrs.

So you have plenty of pectin. But I think we already know that!

We need to home in on the (lack of) fermentation. But you are only one
week in, so there is time to go. Have you ever had fermentation in the
past?

Where do your apples come from? Do you grow them yourself? How are they
grown - young dwarf trees or big old trees? Is there any possibility
that they have been treated in some way that inhibits fermentation? How
are you sterilising your containers? Do you press the juice yourself? How?

[Jan]

If you had an open straight-sided vessel you could easily take the mould
spots off. That is one advantage of it. Mould spots usually attach to
small pieces of floating apple pulp.

That is fair point...

 

The gel is now sinking, right? Is there any sign of fermentation at all?
(I think 12C is rather warm but if you are worried about trying to
encourage fermentation I see why you would maybe do that).

Yes that is the reason why I am increasing the temperature, on the trial batch I keep at 20C I see some bubles catched in the gel

 

We need to home in on the (lack of) fermentation. But you are only one
week in, so there is time to go. Have you ever had fermentation in the
past?

Yes, I hope this time it wil go faster, as I did not sulfite 

Where do your apples come from? Do you grow them yourself? How are they
grown - young dwarf trees or big old trees? Is there any possibility
that they have been treated in some way that inhibits fermentation? How
are you sterilising your containers? Do you press the juice yourself? How?

I am buying them, and already scheduled a meeting with the farmer, so will be able to find more. I am using a mixture of desert apples Jonagold and Idared. Unfortunately as the Apple Wine making tradition get lost in here before the second war, there are not any cider making apples available.

 

I am not using any special cleaning chemicals just hot and cold water. Yes I am using apple press like this one

 

I kept the juice for about 5 days at 8C now warming it up to 12C for two days.

 

What is confusing to me is that the gel formation is a chemical reaction. So how it should look like 24 hours after the calcium is added? Mine was gel in entire demijohn. I am attaching two pictures. Trial batch which is now one week old and kept for 4 days at 20C and a picture of demijohn, showing thin layer of clean juice.

 

Jan

[Andrew Lea]

On 29/11/2013 18:52, Jan wrote:

>
> I am using a mixture of desert apples
> Jonagold and Idared. Unfortunately as the Apple Wine making tradition
> get lost in here before the second war, there are not any cider making
> apples available.

I don't have any experience of keeving such apples. I don't know if
anyone does? The technique was developed for cider apples. So as I say
you are being an experimentalist! I wonder if your fruit is very
commercial and very clean it may have a very low wild yeast load - so
that may be why the gel did not rise. Cider apples in the UK and France
are picked up from the ground and kept for a while before use, hence the
wild yeast populations can be quite high in those apples.

>
> What is confusing to me is that the gel formation is a chemical
> reaction. So how it should look like 24 hours after the calcium is
> added? Mine was gel in entire demijohn. I am attaching two pictures.
> Trial batch which is now one week old and kept for 4 days at 20C and a
> picture of demijohn, showing thin layer of clean juice.

It is difficult without seeing the gel itself, but it does look rather
tight and rigid from the pictures. It has to be loose enough that the
yeast action will make it float to the top and compress it as it does so.

Perhaps the pectin structure in those dessert apples is different to the
pectin structure in cider apples? (That is a serious suggestion - there
is evidence that pectin structures do differ across apple varieties).
Also maybe you do have too much pectin? Perhaps you should not be
macerating dessert fruit pulp before pressing, but pressing it directly?
Again, you are an experimentalist....!

Any sign of progress in the last few days?

[Claude Jolicoeur]

Le dimanche 1 décembre 2013 08:26:55 UTC-5, Andrew Lea a écrit :

> Jonagold and Idared.

I don't have any experience of keeving such apples. I don't know if
anyone does? The technique was developed for cider apples.

I would suppose that Jonagold and Idared could be different from Cortland or Liberty, but I can testify the latter do keeve perfectly well under the right conditions while being dessert fruit.
If the gel is well formed and there is no start of fermentation, maybe just adding a pinch of yeast would help? And when I say a pinch, I mean it - I wouldn't add a full packet because it would start much too vigorously.
Claude

[Andrew Lea]

On 01/12/2013 14:55, Claude Jolicoeur wrote:
>
> If the gel is well formed and there is no start of fermentation, maybe
> just adding a pinch of yeast would help? And when I say a pinch, I mean
> it - I wouldn't add a full packet because it would start much too
> vigorously.

Maybe worth a try, but you do need only a tiny amount.

To try to set some numbers on it, active dried yeast contains about
2*10^10 yeast cells per gram. To match the 'wild' situation, I'd say you
don't want to exceed 2*10^5 yeast cells per ml of juice.

Or in other words you need 1 gram of dried yeast per 100 litres of juice!

If you have less juice than that you need to scale down pro-rata. Unless
you have a milligram balance at home (!) you will have to do that by
slurrying in water and serial dilution.

[Claude Jolicoeur]

Andrew Lea wrote:

If you have less juice than that you need to scale down pro-rata. Unless
you have a milligram balance at home (!) you will have to do that by
slurrying in water and serial dilution.

Slightly off topic, but it is very surprising nowadays what we can buy - for example I recently got a small scale, pocket size, 0.01 g resolution, max capacity 200 g, for 25$... This was unthinkable just a few years ago.
I doubt that the precision really is 0.01g, but even if it is 0.05g, this is still quite good, and plenty sufficient for our cider making needs. It would be good enough for Jan to measure 0.2 grams of yeast...
Claude

[Gary]

It has been my experience that heavy, blocky gel is not a serious problem and it need not prevent success in keeving.  In fact some of my most successful batches started that way.  The short term solution to the solid, blocky gel is a simple one.  If not for mold growing on the surface and inability to skim it off due to shape of the keeving vessel I would advise simply waiting.  Given the presence of visible trapped bubbles and mid-layer of clear cider you descirbe the gel will most likely lift eventually.   Since this case involves visible surface mold that cannot be removed manually I would suggest siphoning to another demijohn (or temporarily to a clean bucket) through tubing that will force the pectin to break up into smaller chunks.  I have used polyethylene tubing of 1/4 inch inside diameter (roughly 6-1/2 mm) for this in the past. I doubt that hose diameter is critical as long as you can get the gel through it and it is not so small and turbulent that it liquefies the gel.  A greater height differential between vessels may be required to provide enough force to shear the gel.  Sometimes a very slight positive pressure is required when a particularly firm gel blocks the tubing but that is tricky and generally unsafe when working with glass vessels that are not designed to be pressurized.  An alternative is to pour gel from one demijohn to another through a funnel (this also breaks up the gel).  It's best to do this while colder so the gel tends to shear into discrete pieces rather than liquefy.  Once broken into smaller chunks it will be easier for trapped juice to be squeezed out of the gel and for the cap to be compressed through normal action of the yeast.  

 

Alternatively you could add a small amount of additional yeast to the bottom of the gel via a tube to generate a bit more CO2 to provide lift.  I don't suscribe to the belief that you must rely on endogenous yeast in keeving and generally use about 1/8 the amount cultured yeast recommended by yeast suppliers.  Compression of juice out of the gel is slower when force is applied from the bottom of a big solid block of gel.  However you should start seeing enough  lifting of the gel to begin to form a crust on the surface even before compression of the gel is complete.  The surface will become dry and (at least in my experience) a less hospitable environment for surface mold.  You will be able to recognized this by a darker, leathery appearance.  However if you do add yeast via a tube after the gel has formed be sure to let your added yeast adjust to temperature of the cider before adding so you don't thermally shock it into complete inactivity.  In normal practice I like to add yeast just as precipitation becomes visible (or viscosity becomes affected) so that more yeast will be embedded in the gel.  The suspended yeast is removed with the gel so fermentation remains slow.  If pectin load is heavy enough to form blocky gel it may be difficult to see.  In that case you can detect the right time to add yeast by measuring gravity with a hydrometer (if you use an open-top vessel).  When readings start to become erratic it's a sign that gel is forming and that it is time to add yeast.  

 

Looking to a longer term solution, an excess of PME (with resulting heavy pectin load) is not a problem if you add CaCl2 with a lighter hand as Andrew suggests.  If suspended pectin is there but precipitation is insufficient you can always add a bit more CaCl2 later.  If pectin is not as heavy as  you think, however, an excess of CaCl2 can make the cider taste salty.

 

 Gary in Indiana 

  

 

   

 

 

[Jan]

I guess we can agree on the conclusion that the yeast activity is week. The first attempt to address this issue was to avoid sulfite, hopping the wild yeast will get more vigorous and will break up and lift the gel. This did not happen so addition of active yeast is required.

 

After observing the gel formation in the trial jar (one week at 20C), the yeast activity is still not strong enough to break the gel nor to allow the CO2 to escape it. From the past year of experience, it took about 4 months to reduce about 50% of the gel, and the juice still did ferment to SG 1000, well at least it was clear.

 

Test one

Out of curiosity I did try a rather aggressive method on the trial jar and did break up the gel with a hand mixer. And voilà, after 24hours it did rise up. See the attached picture. Will watch it to see what is going on.

 

Test two

Another idea how to make the gel less heavy was to mix the gel with untreated juice (I was keeping one bottle aside just for drinking). After mixing it half and half It did not liquefy the gel, however did clear it. That is interesting.

 

Garry suggest breaking the gel by racking it, and I will try this on the demijohns. I however think that my gel must be even thicker than his, as there is no way to liquefy it again, even with hand mixer.

 

There are two ideas why such heavy gel forms, too much pectin or too much of CaCl2. One option is to macerate the pulp, for shorter period of time. In the past even 12, 24, 30 hours of maceration yielded the same result, so maybe no maceration is the option. This however has effect on the juice color and I like it darker, thus inclining to the idea of reducing the CaCl2. Andrew, suggest the soil (where the apples grow) might have excess of calcium, I did reduce it to ¾ (according to KlerCidre kit amount), so will reduce it even more.

 

Gary mentioned that too much of calcium, makes the cider taste salty. I was wondering why last year bottles do have such salty after taste. I did double check all the ppm calculations, and think the amount of CaCl2 was right.

 

Jan

 

[Andrew Lea]

On 02/12/2013 12:46, Jan wrote:
>
>
> Gary mentioned that too much of calcium, makes the cider taste salty. I
> was wondering why last year bottles do have such salty after taste. I
> did double check all the ppm calculations, and think the amount of CaCl2
> was right.

I am a bit worried by this. Can you tell us just how much calcium
chloride you have been adding? It should work out at no more than 400
ppm (expressed as anhydrous CaCl2).

[Jan]

I do have liquid CaCl2 solution diluted at ratio of 520g CaCl2 per one liter. According to the KlerCidre manual, they do recommend to use 427ml of CaCl2 solution for 500l and up to 700l, which is roughly 0,6 – 0,85ml per liter

-          Last year I did use 20ml of the above solution for 25liters of juice SG 1053 (cca 400ppm weight)

-          This year I did use 10ml for 20liters SG 1055 (cca 250ppm)

Jan

[Andrew Lea]

On 02/12/2013 14:38, Jan wrote:
> I do have liquid CaCl2 solution diluted at ratio of 520g CaCl2 per one
> liter. According to the KlerCidre manual, they do recommend to use 427ml

> of CaCl2 solution for 500l and up to 700l, which is roughly 0,6 � 0,85ml
> per liter
>
> -Last year I did use 20ml of the above solution for 25liters of juice SG
> 1053 (cca 400ppm weight)
>
> -This year I did use 10ml for 20liters SG 1055 (cca 250ppm)

From those figures, I agree you were not overdosing the CaCl2. If you
have a successful keeve you do not notice any salty taste because the
calcium stays locked up in the calcium pectate gel which is of course
removed from the system.