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danr
01-20-2013, 05:30 PM
This question relates to fatbloke's response to my comment in another thread that I added Potassium Sorbate to my mead without also adding Potassium Metasulfite. (This was based on the instruction that came with my kit.)

How would malolactic bacteria get into a mead accidentally? In my case, the only ingredients in the mead were 15# of honey and water to 5 gallons with Lavin 71B-1122 yeast and nutrients.

Fortunately, I have no signs of geraniols. I will add the potassium metasulfite when I bottle. I may have been fortunate that the sorbate was added when fermentation was complete and I had a high alcohol content and low temperature (60d F) storage.

fatbloke
01-20-2013, 05:53 PM
The bacteria is like any other, potentially present anywhere.

Yet it doesn't present a problem if sulphites have been added. A campden tablet gives approximately 50 ppm per gallon, and the malo-lactic bacteria is only a problem if the levels of sulphites are at natural sort of levels i.e. less than about 20 ppm.

Hence the use of sulphites/campden tablets and sorbate to stabilise a finished ferment.

With wines, the bacteria for MLF are often added deliberately, but its a natural thing, much like vinegar. You dont need to add the acetobacter to make it. Its present in the environment. But it can be added deliberately to make vinegar.

The use of sulphites prevents that.

Its why its recommended to stabilise with sorbate and sulphite when the ferment is finished (irrespective of the strength of a batch). Then because sulphites can dissipate, they're added every second racking to maintain an appropriate level without affecting the flavour.

Of course, you can just stabilise, then clear a batch with finings and the just add another dose before bottling.....to make sure the batch is preserved in the bottle.

Its entirely your choice.....

Medsen Fey
01-20-2013, 05:54 PM
Lactic acid bacteria are ubiquitous. They can be found on your skin, carried on fruit flies, coating the surface of fruit, floating on dust particles, etc. There have even been strains identified in the honey stomach of bees, so they may be present (though inactive) in honey. If you maintain very strict hygiene, you might keep them at bay, but those choosing to use sorbate without sulfites are rolling the dice.

danr
01-20-2013, 06:42 PM
Guys, thanks for the clarifications. A few followup questions:


Would the potassium sorbate typically only be used at the initial dosing after fermentation is complete even though the potassium metasulfite may be used multiple times?

Should I gently stir the crushed metabisulfite into the carboy before bottling or just drop it in? i.e. What is the correct balance between getting the metabisulfite mixed in vs. concerns of aeration/oxidation.

Does the metabisulfite affect the flavor of the mead after repeated dosings?

My wife is allergic to sulfites. Are there any other options for my future batches of mead?

fatbloke
01-20-2013, 07:25 PM
Guys, thanks for the clarifications. A few followup questions:


Would the potassium sorbate typically only be used at the initial dosing after fermentation is complete even though the potassium metasulfite may be used multiple times?
Should I gently stir the crushed metabisulfite into the carboy before bottling or just drop it in? i.e. What is the correct balance between getting the metabisulfite mixed in vs. concerns of aeration/oxidation.
Does the metabisulfite affect the flavor of the mead after repeated dosings?
My wife is allergic to sulfites. Are there any other options for my future batches of mead?


A, yes. That's correct, but you use both on the first occassion, then as the sulphites dissipate, add more every second racking just to keep the levels to a point where they prevent the problems.

B, Yes, just crush a campden tablet and gently stir it in, so there's not splashing action. If you're not actually doing anything else with the batch, you can just drop the tablet in as it will dissolve over a day or so.

C, Yes, metabisulphite can affect the flavour if used in too higher concentrations. But the point of using it only to the recommended levels as mentioned above means that it's just at a maintenance level i.e. 1 campden tablet will give approx 50 ppm per gallon, I understand that the most sensitive tastes will only notice if it's above 100 ppm - the racking action in between additions is where it dissipates.

D, Allergies can be a pain. Yet sulphites are used in many, many foodstuffs, so it would depend on the level of sensitivity that your wife has to sulphites. The obvious answer is careful production, and using levels of honey whereby you eventually make them strong enough to exceed the tolerance of the yeast - the step feeding process is about the easiest and most hassle free i.e. if you know that a yeast is capable of 16% ABV (I'll use the example of my favourite yeast for traditionals, D21 which is tolerant to that level). So 16% ABV equates to a drop of 118 points. To make a batch that has a starting gravity of 1.118 might, feasibly stress the yeast with all the sugars added up front, so you just make a batch with an SG of say 1.100, get it fermenting, test to monitor where the gravity gets too, then when it's at something in the 1.030 to 1.050 area, you just add enough honey to bring the gravity up by 18 points and it can then be left to ferment dry - presuming dry at 1.000 - if the yeast likes it's environment it might exceed that a bit and get down below 1.000 - either way, you can then back sweeten to your desired level as the yeast won't be capable of refermentation, and just clear it and finish the process in the usual way.

The point of stabilising a batch is to prevent any further fermentation when there's still fermentable sugars available and the yeast has capacity to ferment left. Even the clearest mead will have yeast cells present, unless it's been "sterile" filtered, with a filter gauged at about the 0.25 to 0.40 micron area (and most don't have access to such fine filtration).

If the yeast can't ferment any further then that part is unnecessary. Plus a stringent hygiene regime with all your kit, bottles, siphoning pipes etc, should, theoretically, reduce the chance of infections by spoilage organisms. Any that did get in would, as with the occasional bottle of wine, just be bad luck.

Medsen Fey
01-20-2013, 07:51 PM
Very few people who have "sulfite allergies" are really allergic to sulfites. Many times people who have headaches or other reactions to wines are having them due to biogenic amines or oak extracts. Folks with true sulfite allergies cannot tolerate most dried fruits or a whole host of foods that make adjusting the diet rather challenging.

Nevertheless, if your wife is truly allergic, be careful because all fermentations produce sulfites through the actions of the yeast. Some can produce quite a bit, so she should be careful about drinking any fermented beverage. If she can tolerate meads or wines where sulfited isn't added, an alternative to sorbate that won't be metabolized by bacteria is Benzoate. It is available and can help, though, like sorbate, it may be more reliable if used in conjunction with sulfites.

kudapucat
01-24-2013, 02:34 AM
Now that the OP seems properly answered, I might venture a further related question:

I am planning a Pyment with my friend who makes wine.
He has asked if we should add malolactic bacteria to encourage a malolactic ferment, or if we should try to suppress it?

Bob1016
01-24-2013, 04:19 AM
Do you want to?
The original reason for inoculating with ML bacteria is to hedge your bets: it will probably happen if left alone, and it's better to get a culture that is known to be good as opposed to Russian roulette with wild ML bacteria.
If you like what MLF gives the wine made with the same grapes then I would consider it, just be aware of the nutrient issue. If you'd rather have a crisp/sharp wine (Riesling) then suppress it.
That's my two cents/pence.
P.S. What grape/honey varieties are you using, that will go a long way in telling you what to do.

kudapucat
01-24-2013, 08:31 AM
Honey variety is early summer suburban variety, grape is probably Shiraz or Cabernet Sauvignon.
Usually the wine if given MLF.
Also way OT here, but should I mix honey to a good wine baume (gravity) or boost the pyment past the minimum required for good wine?

fatbloke
01-24-2013, 08:36 AM
My fresh grape pyment last year should have really had MLF done for the grapes but I forgot and sulphited so it was too late by then.

Not that they needed it really because I just carried on step feeding the grape pulp until it pooped out and there's enough residual sugars at them moment to mask any acid issue that might be present.

Bob1016
01-24-2013, 02:41 PM
Ken Schramn (on the jamil show: mead) made a point that he believes payments were originally grape musts with honey added to boost th gravity.
If you want classic carbernet/Shiraz character with a twist, go for a typical wine gravity and do MlF, if you want some sweetness and high alcohol to accompany the spicy bold flavors of those grapes don't add any water, and add honey to a good SG (above the tolerance for the yeast) and avoid MLF (a high alcohol might help, but sulfites are good too).