Malo-lactic fermentation

[Calder]

This came up in another thread, but I thought I'd make a new one to ask the question.

What is malo-lactic fermentation and how do you get it?

 

[pkeeler]

What is malo-lactic fermentation and how do you get it?

It is when special lactic bacteria convert malic acid to lactic acid. You can get it spontaneously or by introducing freeze dried malo-lactic bacteria (MLB). They are a little finicky of pH and temp., so you won't get one if you are outside their comfort zone. Most LHBS carry or can get the MLB, but they are not cheap (compared to freeze dried yeast at least).

Malic acid is not desirable in red wine, which is where MLF is done. Malic acid is the dominant acid in apple cider. I don't know if it would be desirable in a hard cider.

 

[truckjohn]

Frequently, you don't find it... It finds you..... Especially if you ferment sour apples totally dry and bulk age..... All seems quiet during the cold winter - and it "Comes back to life" and starts bubbling away in the spring when the weather warms back up.... This can take a while..

Malic acid is the traditional "Sour Green Apple Candy" flavor.... In a totally dry cider - it can be intensely bitter from the high malic acid content.... If Malo-lactic fermentation happens - you get a less bitter, more smooth tasting "Apple Wine" flavored cider...

Lactic acid is much less bitter and doesn't have the Sour Apple Candy flavor... The flavor is more of a neutral sour and it usually comes along with other flavor compounds that have a "Buttery" essence - like a good chardonnay....

Thanks

 

[dusty1025]

Any chance of a spontaneous MLF when fermenting store bought apple juice? What are the PH and Temp parameters to abide by to get a complete MLF?

 

[gregbathurst]

Yes, MLF is caused by Lactic Acid Bacteria (LAB) and these are pretty ubiquitous in nature. There would be a good chance of contamination during the fermentation process. You need a warm temp, above 65F, a pH above 3.2 and low sulphite levels. Free sulphite is used up during primary so after primary if you don't add camden tablets there is a good chance of MLF. In the long run, unless you keep sulphite levels up you are almost certain to get MLF.

Truckjohn gave a good summary of MLF, the main disadvantage is the raise in pH it causes. If you intend to sweeten its not so important, but a dry cider without MLF is pretty sour.

 

[dinnerstick]

opinions please? last autumn my ladyfriend's father gave me the whole harvest of apples from his tiny tree which makes very sour apples normally destined for the digestive recesses of his horse. i told him i'd make a tiny batch of cider from just those apples, nothing more. i pressed them by hand and got enough juice to fill a 5L water bottle, fermented by natural yeast to bone dry, 5% v/v EtOH. pH low- very low. taste: tart. first sip removes the enamel from teeth. delicious though. sour apple malic acid. i didn't want to age it in the plastic bottle so i bottled after 6 weeks by which time it had cleared pretty well. it hadn't occurred to me that this stuff was going to undergo mlf but it should have. the question is, am i getting MLF in the bottles? what happens when that happens?? i had no intention of opening any bottles for many months.
thanks for input

 

[Yooper]

If you didn't sulfite it, it might undergo MLF in the bottles. If that happens, the bottles will blow.

 

[mak]

Interesting. This might have been the culprit behind my exploding glass bottles.


Question, how do I control MLF in cider? Do I have to add bacteria or would letting the cider sit in secondary be fine?


Thanks in advance

 

[Yooper]

Interesting. This might have been the culprit behind my exploding glass bottles.


Question, how do I control MLF in cider? Do I have to add bacteria or would letting the cider sit in secondary be fine?


Thanks in advance

To inhibit MLF fermentation, sulfites would work. To allow MLF, you can add the MLF bacteria. It may or may not happen spontaneously, so adding the MLF culture would be a good way to do it to ensure it happens.

 

[mak]

Thanks Yooper!

 

[gregbathurst]

If you didn't sulfite it, it might undergo MLF in the bottles. If that happens, the bottles will blow.

Yooper, the amount of co2 produced is fairly small compared to what you get from priming sugar. If you already had a high level of carbonation it might push it over the edge, but its unlikely.

When cider or wine is in 5 or 10 gal containers the amount of co2 produced is quite noticeable, and useful for blanketing and keeping out oxygen, because the liquid is usually already saturated with co2 when the MLF starts. CO2 produced by MLF in a bottle is enough to give it that sour carbonic acid taste and spoil your wine, but otherwise not very significant.

 

[Yooper]

Yooper, the amount of co2 produced is fairly small compared to what you get from priming sugar. If you already had a high level of carbonation it might push it over the edge, but its unlikely.

When cider or wine is in 5 or 10 gal containers the amount of co2 produced is quite noticeable, and useful for blanketing and keeping out oxygen, because the liquid is usually already saturated with co2 when the MLF starts. CO2 produced by MLF in a bottle is enough to give it that sour carbonic acid taste and spoil your wine, but otherwise not very significant.

I've had corks blow from MLF happening in the bottle. If it's capped with crown caps, maybe not. I was speaking from a wine bottle and cork perspective, how I bottle all of my wines/meads/ciders.

 

[dinnerstick]

CO2 produced by MLF in a bottle is enough to give it that sour carbonic acid taste and spoil your wine, but otherwise not very significant.

this suggests that carbonation always imparts a sour carbonic acid taste, is this something that we generally don't notice because the other differences between still and sparkling drinks are so great? i mean that the other senses that the fizziness hits; feeling on the tongue and back of the mouth, more aroma due to evolved gas and aerosols, even sound, obscure the subtle (or not so subtle) differences in flavor due to H2CO3 if you do a side-by-side tasting of pre- and post-carbonation of the same batch?

 

[pkeeler]

this suggests that carbonation always imparts a sour carbonic acid taste,

I don't know if it is sour so much as a bitter taste. Have you ever tasted un-carbonated beer? Very sweet. Carbonation brings enough bitterness to even that out. Carbonation is also sensed separately than flavor in the mouth. Coca-cola syrup is another good example, as it is much sweeter tasting than the carbonated soda; even though it has the same amount of sugar.

 

[dinnerstick]

perhaps a better example is carbonated vs. flat mineral water- there i really taste the sourness when it's fizzy. to me beer tastes so different flat (or 'english' as we call it) vs carbonated, in so many ways, that i just can't believe it can be all down to the carbonic acid. i am guessing the fizzyness must get flavor molecules into places they don't get when it is flat, and the bubbles on the tongue certainly alter flavor perception. ??

but anyways i digress, i am still wondering about this cider i have bottled and potentially undergoing MLF. it has been bottled since the beginning of december, no bombs. if the worst that is likely to happen is that i get a bit of extra CO2 which gives a bit of fizzyness and a little carbonic acid sourness then i'm happy. but... can you pick up any off flavors from MLF in a confined space? now it sounds like a communicable disease

i will open one for the first time just to check the progress. it was so tart at bottling that i should know straight away if it 'malo-ed'

and i do like english cask ales (when they are fresh), i just also like to make fun of the way english people like english cask ales...

 

[gregbathurst]

perhaps a better example is carbonated vs. flat mineral water- there i really taste the sourness when it's fizzy. to me beer tastes so different flat (or 'english' as we call it) vs carbonated, in so many ways, that i just can't believe it can be all down to the carbonic acid. i am guessing the fizzyness must get flavor molecules into places they don't get when it is flat, and the bubbles on the tongue certainly alter flavor perception. ??

but anyways i digress, i am still wondering about this cider i have bottled and potentially undergoing MLF. it has been bottled since the beginning of december, no bombs. if the worst that is likely to happen is that i get a bit of extra CO2 which gives a bit of fizzyness and a little carbonic acid sourness then i'm happy. but... can you pick up any off flavors from MLF in a confined space? now it sounds like a communicable disease

i will open one for the first time just to check the progress. it was so tart at bottling that i should know straight away if it 'malo-ed'

and i do like english cask ales (when they are fresh), i just also like to make fun of the way english people like english cask ales...

Yes, carbonated mineral water is good for showing that carbonic acid taste. It depends a lot on the kind of drink how it affects the overall flavour. In white wine or cider it's ok, just adds a bit of lift or tingle, but in dry red table wine its a real killer, makes the wine taste horrible IMO.

A possible effect of wild MLF is that it may not be done by desirable micro-organisms and may result in off- flavours. There are literally thousands of LAB bacteria species and some can give a very nasty flavour. If you inoculate you avoid this risk.

 

[CidahMastah]

There is a lot of misinformation on this thread. Here are a few key points from personal experience and factual printings:

1. It will not naturally occur in a pasterized cider (only fresh pressed).
2. It can be supressed by sulphites, but can beat them out too (have had several ciders start malo with a 90PPM installment of kmeta).
3. Malolactic acid doesn't increase the acidic flavor in a cider, it reduces it. It gives a buttery flavor similar to a chardonnay or pinot gris (im my opinion improves the cider).
4. Allowing it to occur makes for a more stable, less acidic tasting more full bodied cider.
5. It can occur simaltaneously with your regular fermentation, depending on your yeast strain.
6. If you bottle your cider and it starts on its own (storage of the bottles above 50F is risky), expect funky tasting cider and/or broken bottles. The off flavors are less about carbonic acid, ,pre about more about funky gases produced by the fermentation. As with regular fermntations, under airlock, these fgasses dissipate. Locked in your corked bottle, they stay in solution = funky wine.
7. All of the wild malolactic fermentations I have had occur (usually 80% of my cider yield) is a good thing. Never had a bad malo ferment to date (never bought a culture - they were all naturally occuring).
8. Malo ferments can occur from 50F+, but prefer an ideal ferment temp of 63-66F (they occur at higher temps as well, but produce more esters, which I tend to not prefer - the former range is my preferance based on my results).
9. Malo ferments are predictable, and don't start and stop with teh seasons. The reason they start is proper temp, if the temp dips low, they slow or stop. In my cider cellar, I have constant temps, and the malo ferments start like clock work after the initial ferments. This is why I never bottle anything until 3-6 months. It sits in bulk aging vessels under airlock until the coast is clear.
10. Malo ferments tend to be slow burners. That is, they usually take a month or two to wrap up.

To mitigate it, you can always cold store your cider at 45F or less.

You may or may not like the taste - but I don't know what you like, I would expect that you would enjoy it if you like white wines like those described.

 

[clayroc]

So I just pit on a batch from pasteurized apple juice. How should I go about encouraging malo-lactic fermentation then?

 

[CidahMastah]

So I just pit on a batch from pasteurized apple juice. How should I go about encouraging malo-lactic fermentation then?

For pastuerized juice - you would need to buy a culture (LHBS) or online. Past. kills the naturally occuring malo yeast.

 

[dinnerstick]

hi i just tried my first bottle from this batch, it tastes like it has definitely MLFed, the face puckering sourness has subsided and it is now smooth at the finish. which suggests it had mlf in the bottle since it went into the bottles sharp as anything. but they are only a tiny bit carbed (as planned) and there is nothing i would consider an off flavor. nothing garbagey, farty, nothing sour in the smell. in fact it is delicious. still tart at the onset, light and refreshing in the middle, and then really smooth and almost a hint of caramel at the finish, and it stays appley on the palate after each sip.
het gaat pissen als een twee piemelig hond op een platte steen!!

 

[clayroc]

For pastuerized juice - you would need to buy a culture (LHBS) or online. Past. kills the naturally occuring malo yeast.

Ok thanks, I will get on that

 

[gregbathurst]

There is a lot of misinformation on this thread. Here are a few key points from personal experience and factual printings:

1. It will not naturally occur in a pasterized cider (only fresh pressed).
2. It can be supressed by sulphites, but can beat them out too (have had several ciders start malo with a 90PPM installment of kmeta).
3. Malolactic acid doesn't increase the acidic flavor in a cider, it reduces it. It gives a buttery flavor similar to a chardonnay or pinot gris (im my opinion improves the cider).
4. Allowing it to occur makes for a more stable, less acidic tasting more full bodied cider.
5. It can occur simaltaneously with your regular fermentation, depending on your yeast strain.
6. If you bottle your cider and it starts on its own (storage of the bottles above 50F is risky), expect funky tasting cider and/or broken bottles. The off flavors are less about carbonic acid, ,pre about more about funky gases produced by the fermentation. As with regular fermntations, under airlock, these fgasses dissipate. Locked in your corked bottle, they stay in solution = funky wine.
7. All of the wild malolactic fermentations I have had occur (usually 80% of my cider yield) is a good thing. Never had a bad malo ferment to date (never bought a culture - they were all naturally occuring).
8. Malo ferments can occur from 50F+, but prefer an ideal ferment temp of 63-66F (they occur at higher temps as well, but produce more esters, which I tend to not prefer - the former range is my preferance based on my results).
9. Malo ferments are predictable, and don't start and stop with teh seasons. The reason they start is proper temp, if the temp dips low, they slow or stop. In my cider cellar, I have constant temps, and the malo ferments start like clock work after the initial ferments. This is why I never bottle anything until 3-6 months. It sits in bulk aging vessels under airlock until the coast is clear.
10. Malo ferments tend to be slow burners. That is, they usually take a month or two to wrap up.

To mitigate it, you can always cold store your cider at 45F or less.

You may or may not like the taste - but I don't know what you like, I would expect that you would enjoy it if you like white wines like those described.

1- MLF can occur in any cider - as soon as cider is exposed to air there is a chance of contamination. Pasteurisation is only good until you open the container.

2- Wild MLF is extremely unlikely with a well sulfited cider, but I am talking about free not total so2. If the so2 has been bound by fermentation or oxidation, then MLF can occur in the presence of sulfite.

3- I was referring to the acidity from dissolved co2 which forms carbonic acid, a well documented phenomenon which I shouldn't have to explain.

4- "expect funky tasting cider and/or broken bottles. The off flavors are less about carbonic acid, ,pre about more about funky gases produced by the fermentation"
As I said, not enough co2 to cause broken bottles, you must have had residual sugar. As for "funky gases", this is a pretty weird concept, not one I have ever heard of.

7- " Never had a bad malo ferment to date (never bought a culture - they were all naturally occuring)."
This may be your experience and wild MLF is usually ok but it is definitely possible to get a bad wild MLF, and this is why wineries spend a lot of money on cultured MLF, though you seem to know more about MLF than any winemaker I have met.

8- You will not get MLF at 50F, the recommended temp is 20C - 68F.

I suggest to anyone not sure who to believe about this, do some research of your own. MLF is important to cider and you need a good understanding of the process.

 

[CidahMastah]

1- MLF can occur in any cider - as soon as cider is exposed to air there is a chance of contamination. Pasteurisation is only good until you open the container.

2- Wild MLF is extremely unlikely with a well sulfited cider, but I am talking about free not total so2. If the so2 has been bound by fermentation or oxidation, then MLF can occur in the presence of sulfite.

3- I was referring to the acidity from dissolved co2 which forms carbonic acid, a well documented phenomenon which I shouldn't have to explain.

4- "expect funky tasting cider and/or broken bottles. The off flavors are less about carbonic acid, ,pre about more about funky gases produced by the fermentation"
As I said, not enough co2 to cause broken bottles, you must have had residual sugar. As for "funky gases", this is a pretty weird concept, not one I have ever heard of.

7- " Never had a bad malo ferment to date (never bought a culture - they were all naturally occuring)."
This may be your experience and wild MLF is usually ok but it is definitely possible to get a bad wild MLF, and this is why wineries spend a lot of money on cultured MLF, though you seem to know more about MLF than any winemaker I have met.

8- You will not get MLF at 50F, the recommended temp is 20C - 68F.

I suggest to anyone not sure who to believe about this, do some research of your own. MLF is important to cider and you need a good understanding of the process.

1. it is very rare to catch a malo strain from the air, could it happen? Perhaps if you have a n old cider mill around. Perhaps if you have apples smushed on your floor, but highly unlikely if you are making cider from concentrate.

2. I am talking about free so2 as well. My statement stands as is.

3. CO2 carbonic acid doesn't contribute significantly to palatable acidity.

4. This is you showing your insecurity, my statement stands. Yooper indicates she has experienced broken bottles from malo ferment - are you calling her a liar?

7. My statement is a fact, I have no bad experience with it - are you calling me a liar?... Then please start taking notes - because you clearly don't know what you are talking about.

8. My statement stands - I have experienced this with my ciders. Again, calling me a liar?

I suggest that when you start making ciders and having advice that is more than anecdotal please check back in. I have experienced the things I have written above with my ciders, so they are true statements. You howe3ver have consistently proven to me, you read a few cider books and pawn off the information as your own experience (not helpful).

Not sure why you get a trip posting things on here that you haven’t experienced personally, then calling people who have liars. You are not giving good advice, and it isn’t helpful.

From the great old Clint Eastwood. Gregbathurst - you are a legend in your own mind

 

[CidahMastah]

hi i just tried my first bottle from this batch, it tastes like it has definitely MLFed, the face puckering sourness has subsided and it is now smooth at the finish. which suggests it had mlf in the bottle since it went into the bottles sharp as anything. but they are only a tiny bit carbed (as planned) and there is nothing i would consider an off flavor. nothing garbagey, farty, nothing sour in the smell. in fact it is delicious. still tart at the onset, light and refreshing in the middle, and then really smooth and almost a hint of caramel at the finish, and it stays appley on the palate after each sip.
het gaat pissen als een twee piemelig hond op een platte steen!!

Nothing like farty cider hahah - too funny.

It might have just been aging, or you may have just been lucky - but malo in a sealed bottle is something of a risk, something you can plan to control in the future.

Glad it didn't give you stank cider

I am glad people are getting interested in malo ferments. It seems like a lot of people opt for the ale yeast draft style cider that is cold crashed to leave residual sugar. Don't get me wrong, I love me some draft cider. However the malo ferment cider is a tasty treat, and should be pursued equally.

 

[gregbathurst]

Cidermastah, I am curious to know how you test to see that MLF has started and finished. This is a problem for winemakers, but red wine doesn't have as much malic. In lab classes I did a Thin Layer Chromotography (TLC) to test for malic, lactic and succinic acid. There are titration tests you can do but I don't think they are as reliable. I find that the pH for cider goes up by about 3 points after MLF, seems a pretty good way to tell if its happened but doesn't tell you about the progress of a MLF.

Yesterday I pitched Oenococcus oeni VP41 into my latest cider which I pressed last tuesday. By pitching the culture I can be pretty sure it will start soon and finish in a week or two, otherwise it would be very hard to tell when wild MLF is starting or finishing. The culture cost me $38 so its only worth buying if you need to treat a lot of cider. I make red wine as well so I have lots of uses for the culture.

 

[CidahMastah]

When there is a lull in primary ferment at 6-7 week mark for me do to my racking schedule at 3-4 weeks. This is followed by (usually) 4-8+ weeks of very low level co2 bubbles rising from the fermenter. When it subsides the ferment is over. I do a taste test about 3 weeks into the suspected malo ferment and taste is the secondary verifier (sight and experience being the first).

One thing I immediately observed from my lab and reasearch work history was.... things happen very differently outside the lab.

 

[gregbathurst]

You can't reliably tell if MLF is happening just from some bubbles. It might be MLF or, a bit of residual sugar, or just some dissolved co2 coming out of solution. Do you do any pH testing? What is your average rise in pH or drop in TA from the start of fermentation to bottling?

 

[clayroc]

Hate to interrupt you "discussion" but was wondering if you knew a good online source to get a culture?

 

[gregbathurst]

Sorry, I'm in Australia, I get my culture from winequip but you would have to order it from in the USA or Canada. It has to be kept cold so order it early in the week and put it straight in the freezer when you get it. Winequip post it with an icepac.

 

[clayroc]

Well I would pitch it right away