Yeast Nutrients and Sulfite

[Johnny_M]

I would like to gauge the more experienced among us about these topics in more depth. I am wondering what the thoughts are on using nutrients. I have yet to pitch nutrients with my yeast for fear that the fermentation would be too quick because even in temps in the 50-62F degree range my fermentations are happening at a very fast pace. (I have pitched both EC-1118 and Red Star Champagne yeast / 1 pack per 5 gallon batch). My cider usually ferments to dry in 2 weeks, with starting SG in the 1.05 range. The second topic I like to discuss along this same line is sulfite or campden tablets. I have always pitched this as well because I have read that there is no way to stop other organic growth in the pH range that is acceptable for a drinkable cider.

The reason I bring these two topics up together is that I have noticed a slight sulfur smell with the batches I have made. I understand this is a consequence of stressed, low nutrient yeast, but I am also wondering if this could also be caused by the addition of sulfite alone. I understand that aging can reduce this smell, but rather than worry about it too begin with I'd like too try to avoid it in future batches. A few questions this brings up is:

• Do you add nutrients to your cider? If so have you tried without?
• What are the pros and cons of nutrients?
• Do you skip sulfiting your cider? If so have you ran into any issues because of it?
• How many times and at what rate do you rack off of the lees to try to limit yeast population and overall fermentation speed? ( I hear this helps with sulfur smell as well)

I am left with some other questions regarding sulfur from bottle fermentation for carbonation, but I will see what kind of discussion this thread brings before I ask.

 

[Maylar]

You'll get a wide range of opinions on this, as we are rather diverse in our approach.

• Do you add nutrients to your cider? If so have you tried without?

Always, unless doing a wild ferment.

• What are the pros and cons of nutrients?

Pro is that it keeps the yeast healthy and far less likely to make H2S sulfur. I don't know of any cons.

• Do you skip sulfiting your cider? If so have you ran into any issues because of it?

I sulfite before pitching to control wild yeast and microbes. I use fresh pressed juice, so it's a concern. I'll use a half dose if doing a wild ferment. I also use it when racking for extended aging because it helps prevent oxidation, and also at bottling time (smaller amount) because it helps the potassium sorbate stabilizer that I use.

• How many times and at what rate do you rack off of the lees to try to limit yeast population and overall fermentation speed? ( I hear this helps with sulfur smell as well)

I've tried Claude Jolicoeur's methods of multiple rackings to reduce yeast biomass and slow down the ferment, but honestly without temperature control (it needs to be cold) it doesn't slow down much at all.

My standard protocol is to ferment in a bucket until 1.006 - 1.010 then rack to a carboy with no headspace. I may oak the cider for a few months. Then rack once more for permanent storage (or to the keg) with sulfite.

 

[RPh_Guy]

I would like to gauge the more experienced among us about these topics in more depth.

Engage?

Do you add nutrients to your cider? If so have you tried without?

Yes and yes.
If pitching yeast I almost always use Go-Ferm at least.

What are the pros and cons of nutrients?

Pros:
Fast and reliable fermentation with minimal off flavors and increased ester expression for estery strains.

Cons:
Expense.
If you don't control fermentation temperature, it will increase. Increased temperature causes incremental loss of aromatics.

It's not speed that's a problem, it's temperature.

Do you skip sulfiting your cider? If so have you ran into any issues because of it?

There are two times you can add sulfite.

Pre-fermentation:
I've used unpasteurized juice with and without pre-fermentation sulfite with pitched yeast. Properly rehydrated and attemporated commercial yeast will assuredly dominate the wild microbes either way. Some aggressive yeasts like EC-1118 that can ferment cold, have very short lag times, and produce both kill factor and sulfite are particularly suited for dominating.
I also allow fully wild fermentation in some batches, with no sulfite. Some I pitch a little Brett in addition to the wild microbes.
If you use pasteurized juice then pre-fermentation sulfite is 100% unnecessary.

Post-fermentation:
I only add sulfite if I won't be bottle carbonating. I keep the fermenter sealed during aging so as not to introduce oxygen.
If you stabilize with sorbate, you should always use sulfite with it.

I've had only one issue with wild microbes. I sulfited and pitched something commercial (Cote des Blanc maybe?) and during aging it developed a pellicle and had really great Brett aroma. Unfortunately under the pellicle there was a huge amount of H2S and other compounds possibly mercaptans and/or thiols. It was a 1 gal batch so I just dumped it after some trials with copper failed. I could possibly have saved it with more effort.

How many times and at what rate do you rack off of the lees to try to limit yeast population and overall fermentation speed? ( I hear this helps with sulfur smell as well)

I leave in primary. Allowing it to sit on the lees generally doesn't cause issues, and certainly can provide benefit. However if there's a lot of H2S produced during fermentation it possibly is best to rack.

H2S issues can usually be solved with nutrients and/or aeration +/- copper +/- ascorbic acid.

I am left with some other questions regarding sulfur from bottle fermentation for carbonation

H2S production when bottle carbonating certainly can be a problem, this is why prevention is a good idea. Use low-H2S strains and nutrients. Pitching fresh properly rehydrated yeast at bottling may also be helpful.

As @Maylar said, there are plenty of different methods you can use.
Cheers

 

[Johnny_M]

I've tried Claude Jolicoeur's methods of multiple rackings to reduce yeast biomass and slow down the ferment, but honestly without temperature control (it needs to be cold) it doesn't slow down much at all.

I read a study which backed up his claim, but they were also studying a huge batch size. I tried this year to rack early (day 7) then do a second rack, but by the time I got there (day 13) the batch was already down to around .999 SG. My must was never over 60 degrees so that is why I have never added nutrients. It seems to me the yeast are able to produce enough to eat through the sugar in 2 weeks so whats the point, but as long as it won't speed up fermentation I will use it next time just to cut the sulfur smell issue so it won't be an issue.

I sulfite before pitching to control wild yeast and microbes. I use fresh pressed juice, so it's a concern. I'll use a half dose if doing a wild ferment.

I use fresh pressed as well. When you say half a dose about how many PPM are you using? I have done about 150ppm because my juice has always been in the 3.6-3.8 pH range. I never want to add any more because I know the yeast I use can produce it so I am pretty much at my upper limit of what is safe. Have you seen any sulfur smell with sulfite pitching a whole dose or does it seems more tied to yeast nutrient in general?

 

[Johnny_M]

H2S issues can usually be solved with nutrients and/or aeration +/- copper +/- ascorbic acid.

I was thinking of trying copper with this batch if the smell still lingers after I let it clarify for a few months. I will also pitch some nutrients before bottle carbonating to hopefully avoid any extra during the bottle fermentation.


Seems the consensus across the forum is that sulfur smell is strictly from stressed yeast producing H2S and not so much from sulfite addition being noticeable to a discerning pallet. In that case my new protocol will be to add nutrient and continue to sulfite. Maybe there is a possibility to reduce the amount of sulfite in both the case of any taste/smell and so that I have other bottling / aging options in the end. Guess some more trial and error is in order next year.

Thank you both for your replies and information.

 

[RPh_Guy]

Here's what I think we know:

Sulfite does NOT add flavor or aroma even in high levels of the bisulfite form.
However:
High levels of molecular SO2 concentration (above 1.0-1.2ppm) causes a noxious aroma / choking feeling.

The anti-microbial activity of sulfite is entirely from the molecular SO2 form, which is highly dependent on pH.
3.6-3.8 is too broad of a range to have any kind of precision. For example, 75ppm of free sulfite is 0.76ppm molecular at pH 3.6, and 1.20ppm molecular at pH 3.8, which as you can see is a huge difference (58% higher).

"Full dose" is 1.0ppm molecular SO2.
"Half dose" is 0.5ppm molecular SO2.

CJ assumes 50% of added sulfite becomes bound to molecules in the must and therefore unavailable. The data supporting this assumption is woefully inadequate in my opinion. Quoted figures I've seen range for 30-70% binding, which is ridiculously broad and also doesn't even make sense to be expressed as a percentage since there are a finite number of binding sites in the must.
Furthermore you need to account for the level of oxygen in the juice, which directly inactives the sulfite.
The result of all these unknowns is that the only way to know is to measure the free sulfite concentration. For those of us that don't measure, we're really just using a wild guess.

Most people using his figures for "full dose" (assuming 50% binding) seem to have problems getting fermentation to start, so I definitely don't recommend his numbers. "Half dose" (i.e. assuming no binding) seems to produce good results anecdotally from myself and others. For example I've run an experiment where I sulfite unpasteurized juice to 1.0ppm molecular SO2 (assuming zero binding) and it kept the juice stable for at least 7 days at 70-75°F, which in my opinion clearly demonstrated full microbial suppression since fermentation would normally begin within 1-2 days without sulfite.

Clear as mud?

Seems the consensus across the forum is that sulfur smell is strictly from stressed yeast producing H2S and not so much from sulfite addition being noticeable to a discerning pallet.

Correct, but:
Yeast are very prone to producing H2S in the presence of sulfite, so yes, sulfite can contribute to H2S formation when combined with active yeast.

Before pitching you need to thoroughly aerate in order to convert all of the sulfite to sulfate, as well as introduce oxygen for the purpose of yeast health.

Maybe there is a possibility to reduce the amount of sulfite in both the case of any taste/smell and so that I have other bottling / aging options in the end.

What are you saying?

 

[bmd2k1]

Some yeasts are Much bigger nutrient hogs than others. My fav - D47 - has Very Low nutrient reqs - I never use it during fermentation & have had Zero issues.

Cheers & Good luck [emoji111]

 

[Johnny_M]

What are you saying?

What I mean to say is if it did affect flavor I could maybe pitch less. But more to my point I know EC-1118 I'm using produces sulfite and how much I pitched could possibly be close to 150ppm so I'm reaching the upper dose of what is safe to drink (under 200ppm). I think the final point I was trying to get at was a misunderstanding on my part which is the chemical process in which sulfite works to reduce oxidation. I guess once its in the must it will do it's job and there would be no need for me to add more at say an aging phase anyhow. If that's the case why not add it all upfront and forgo any addition in the end unless in too much quantity it disturbs the yeast which seems to be the case by what you have written above.

 

[blasterooni]

Boy, a lot was discussed here, a result of a great question, or questions in this case. Though i am mildly buzzed, i will suggest trying an ale yeast like nottinghams, that might chill things out a bit. (Ill have to reread this thread when im a bit more "fresh" as it were. I keep having to correct me damb spellin!)

 

[RPh_Guy]

OK so here's what happens:

First you decide whether you want to add pre-fermentation sulfite, which as I mentioned certainly isn't necessary. If you do, you also need to decide to what extent you want to inhibit the wild microbes. In other words: choose a molecular SO2 target.
If the juice is over 3.8 pH it needs to be acidified.
SO2 production by the yeast doesn't come into play at this point because it doesn't help you reach your target molecular SO2.

Once you add sulfite, the portion of molecular SO2 kills, damages, or otherwise inhibits susceptible microbes in the unpasteurized juice.

After 24 hours or more, you need to aerate the must. The oxygen reacts with sulfite to form sulfate, and has no further effect besides to increase the perception of dryness.
If you don't adequately aerate, then your fermentation may be inhibited and/or likely to produce off-flavors like H2S.

Fermentation proceeds once you pitch yeast (or even if you don't pitch yeast, especially with low sulfite addition).
Any remaining sulfite (if you didn't adequately aerate) will be blown off by the large amount of CO2 release.
Some yeast strains produce variable amounts of sulfite.

After fermentation you need to decide if you want to add sulfite to keep the cider stable. Without adding sulfite at this stage, the cider is susceptible to wild microbe activity (which isn't necessarily bad) AND damage from oxidation.
At the time of consumption you want the molecular SO2 to be 0.8ppm or less.
The bisulfite ions protect against oxidation.
Post-fermentation sulfite is also optional. If you want wild microbes (like Brett) to develop flavor or you want MLF to proceed, you should not use sulfite before those things occur.
If you manage to avoid problems from oxygen before packaging, then bottle carbonation eliminates the need for sulfite because it's protected from oxygen by the packaging process.

If stabilizing with sorbate, sulfite should always be used.

The idea that 200ppm or higher of total sulfite may be somehow unhealthy is nonsense. Once it reacts with oxygen or released as SO2 gas, how the heck could it have any impact on your health? It's no longer present as sulfite.
The limit is there to prevent commercial wine makers from being stupid and using rotten fruit, which requires more sulfite to inhibit the microbes.
This isn't something you need to worry about as a home brewer.

Hope this clears things up.

 

[Johnny_M]

Hope this clears things up.

Yes, I do appreciate it. I had a grasp of like 50% of it I think I'm 100% there now. I wasn't sure how much SO2 stayed around during the whole process and I haven't aerated properly. Now that with the combined knowledge that I shouldn't expect any real reduction of quality by adding yeast nutrient I think I will have solved my problems going forward.

I was inspired by the earlier conversation to start a 1 gallon test batch tonight to see how it will differ from my bigger batch adding nutrient and aerating after sulfite addition.

Thanks again for the info.

 

[madscientist451]

I've been making cider for 15+ years, always use juice from local orchards or press my own.
My approach is to do as little as possible to the cider, let the cider be what is going to be. I've had mixed results, but the cider has gotten better as I've become more selective with the varieties of apples I'm using.
I don't use nutrients.
I use the low temperature and slow ferment approach.
I start gathering apples in late September from various sources, but don't press until about a month later in late October.
Pressing wraps up in mid December. This schedule provides low temperatures in my basement for slow fermenting. I can also set my fermenters outside to cold crash for a week or so before racking.
I generally don't use sulfite in my cider.
3-5 batches a year on average and had sulfur in one batch when I used Nottingham. I haven't used Nottingham yeast in my cider since then.
The Nottingham yeast may not have caused the problem, and I've used other English ale yeast without issues. I'm not sure what the problem was, but that batch was my only drain pour in 15 years.
I usually only rack the cider once, from primary, to a smaller carboy for aging/storage.
I've done many experiments with all kinds of apple varieties and yeast combinations and have come to the conclusion that if you don't start with really good apples/juice, you can't expect to make a very good cider.
I'm experimenting this year with 100% Brett in primary but haven't tasted it yet.

 

[Johnny_M]

I use the low temperature and slow ferment approach.

What temp range do you shoot for? I brew my cider in a garage in the fall-winter. The temps in it are between 50-60F, but my fermentations are still fairly quick. I have thought of options, modified freezer, water bath, and just buying a wort chiller to purpose as a temp control. I don't know if any are worth the effort. I want to see how different levels of sulfite stress my yeast and how much difference nutrient makes before I start getting into other control methods.

I'm fairly new to this so it will just take some more experience and tests on my end before I know what works best for me. I like to hear some options and ideas from those who have done it a bunch of times before though.

 

[dmtaylor]

I never use nutrients or sulfites in my ciders. Funny... they turn out great without any.

One thing I do advocate is for pasteurization of the juice prior to fermentation -- 150-160 F (about 68 C) for about 10 minutes. Then cool and pitch a good yeast (I almost always use Cote des Blancs). I usually don't care much for wild fermentations. Personal preference. I do have a wild batch going right now, but I know it's a crapshoot as to how well it turns out. Sometimes great and sometimes not. We'll soon see.

The best thing that helps make great cider is PATIENCE. Any and all sulfur from the fermentation will ALWAYS disappear all by itself. Patience also results in a crystal clear cider every time, without need for any pectinase or gelatin or other agents. PATIENCE. I usually leave my ciders sit from October until at least February/March before even thinking about bottling them. And often way longer, mostly just because I'm super lazy. I ferment around 55-60 F (13 C) for most the time. It really just sits in my cold basement through winter until I get around to bottling.

Meanwhile, my wild ferment is in the refrigerator in the original jug at 40 F (4 C). Anyone who says fermentation quits at this cold temperature is totally wrong -- it chugs away fine, and quicker than you'd expect.

 

[RPh_Guy]

With regard to "sulfur" going away on its own, YMMV.

When H2S is left in the cider for too long without intervention I often detect residual off flavors (mercaptans/thiols) even after the H2S has oxidized or evaporated. This occurrence is documented in winemaking literature.
However I'm a super taster so I detect compounds at lower levels than most other people, so this may not be a problem for you.

A conservative dose of copper helps a lot in my experience.

 

[balrog]

Slightly

...If pitching yeast I almost always use Go-Ferm at least.

Pros:
Fast and reliable fermentation with minimal off flavors and increased ester expression for estery strains.

Do you find increased ester expression in beer yeasts when using nutrients, Go-Ferm, whatever?

 

[RPh_Guy]

Scientific literature consistently shows us that nutrients increase ester production. I don't think there any reason to doubt that's the case.

 

[balrog]

thanks, it was just the first time I'd seen that. I don't get out much and need to read more.

 

[Maylar]

Scientific literature consistently shows us that nutrients increase ester production. I don't think there any reason to doubt that's the case.

Yet there's another thread here that claims the opposite: https://www.homebrewtalk.com/forum/threads/dap-and-ester-lack-of-production.672590/

Though they speak of inorganic nutrients (DAP) in that thread, which probably makes up the vast majority of what cider makers use.

 

[RPh_Guy]

Yet there's another thread here that claims the opposite: https://www.homebrewtalk.com/forum/threads/dap-and-ester-lack-of-production.672590/

Though they speak of inorganic nutrients (DAP) in that thread, which probably makes up the vast majority of what cider makers use.

The scientific literature is consistent based on every study I've ever seen. If someone has conflicting scientific evidence, they should publish.
Otherwise they probably aren't correct.

File attached, studying DAP specifically. Easy to find articles about this

 

[RPh_Guy]

Here's another, for good measure.

 

[Maylar]

Thanks. Now I feel better about using DAP in my ciders.

 

[madscientist451]

What temp range do you shoot for? I brew my cider in a garage in the fall-winter. The temps in it are between 50-60F, but my fermentations are still fairly quick.

Low to mid 50's is where it usually is. I don't know if its BS, but some people say that apples that come from orchards with high nitrogen usage will ferment differently than apples that come from older, established orchards with no fertilizer.
I've noticed a huge difference if I use tree-ripened fruit. Commercial orchards have to pick their fruit before its ripe, otherwise they'd get too much damaged fruit which would bring lower prices. Apples will ripen somewhat after they are picked, but the ripening is different compared to apples that are ripened on the tree.
I try to hold my apples in storage 30-60 days before pressing.
So with all the differences in apple varieties, climate differences, nitrogen inputs in the orchard and degree of ripeness when harvesting/pressing, there are really just too many variables to pin down what you have to do to make good cider, In the end, you have to make do with the apples or juice that you can get, and try to figure out what works and doesn't work for you.