View Full Version : Pastuerization to prolong stability of Mead

12-10-2008, 11:32 AM
To All Mead heads.

I'm told that with alcohol present in all Meads that pastuerization is not necessary. I'm skeptical. I know that unfiltered Melomel's will settle out over time and thus loose critical fruittiness, but is the potential for bacterial growth non-existant ?


12-10-2008, 12:16 PM
I can't seem to find any really hard facts that answer the question specifically, however here are a few things to consider I found googling around the internet:

-- Bacterial growth begins to be inhibited around 10% alcohol

-- Bacterial growth begins to be inhibited at PH levels below 4.6

-- Honey is a natural "Microbial Inhibitor"

If you're really worried about it, you can use sulfite to chemically pasteurize the honey. Most of the containers of sulfite I've bought give directions on this. I'm thinking it's something like 2/3 teaspoon per 5 gallons, then you let it sit for a day (or something like that).

12-10-2008, 12:32 PM
The preponderance of evidence from thousands of years of vinology (and, I suppose we could call it, "meadology") should quell your skepticism. But if not, you should realize that at least in meads that have been fermented to dryness, there is very little in the way of nutrient contained in the result to be of much value for the vast majority of microbes out there. While there are some infectious agents that can live in a relatively high alcohol, low pH environment (malolactic bacteria and acetobacter are two that come to mind), their introduction to the finished mead can be effectively managed in most cases by practicing good sanitation technique with equipment and containers. So, while finished mead or wine isn't inherently microbially stable, it presents a rather hostile environment to most of the airborne infectious agents out there. Full pasteurization is thus not necessary, and in fact it will change the organoleptic properties of the result -- and not in a good way.

Let me suggest that you go to the main Gotmead page and read the Mead Newbee's Guide. I think that you might have some general misconceptions about mead that might be cleared up if you read that excellent multi-page guide to making and keeping meads.

Dan McFeeley
12-10-2008, 02:41 PM
To All Mead heads.

I'm told that with alcohol present in all Meads that pastuerization is not necessary. I'm skeptical. I know that unfiltered Melomel's will settle out over time and thus loose critical fruittiness, but is the potential for bacterial growth non-existant ?


Hello magarcia12!

There was some research by the late Robert Kime, out of the University of Cornell, on this subject. He was trying to find ways to eliminate off and bitter flavors in mead, and found that even flash pasteurization was detrimental to the flavor of the mead. That was how he turned to ultra filtration of the honey, prior to fermentation.

(Webmaster note: You can read the article here (http://www.gotmead.com/index.php?option=com_content&task=view&id=324&Itemid=64))

A milder form of pasteurization can be done at home -- bring the temperature of the honey must up to 150 degrees F and hold for 15 minutes. That will do the trick, according to the definition and procedures for pasteurization.

It's a question as to whether or not this is absolutely necessary. Honey has a high osmotic pressure, and will kill off any microorganisms that happen to drop into it. Honey has been used to promote healing of wounds, and you can apply it as it is, to an open wound. Do a web search for medicinal use of honey.

In meadmaking, the chief concern is not so much the honey must, but the cleanliness and sanitation of the materials used to make mead.

Hope this is helpful!

Medsen Fey
12-10-2008, 04:52 PM
but is the potential for bacterial growth non-existant ?


Heck no!

Now, the potential for harmful/toxic organisms to grow in mead is essentially zero, but spoilage organisms can definitely take over your mead. As outlined in the prior posts, the potential for mead spoilage may be less than with comparable wines as there tends to be little if any nitrogen nutrient left in a mead (at least as a Show mead or with many historic recipes).

With the modern practice of adding nutrients it is very possible to leave extra nutrients in the mead, and if residual sugar is also present, spoilage organisms can have a field day with it unless your alcohol level is in the 18-20% range. Even a dry mead may have unfermented pentose and hexose sugars that yeast don't metabolize well but bacteria can. What's more, aging on the lees releases all kinds of nutrients into the mead (that's why it is done to support malolactic fermentation in wine).

Does that mean you need to pasteurize? No. Alcohol provides some protection, a low pH is protective (esp <3.5), using sulfites provides protection, using good sanitation provides protection, minimizing exposure to oxygen provides protection, and keeping it cool provides protection. Is this a guarantee that you won't have some nasty critter take over your mead? No. But it does mean that the likelihood can be quite low. I do not pasteurize my meads (with the possible exception of the estufa treatments for my Meadeiras, but that's another topic) and I have not yet had a mead taken by spoilage (knock on wood - though some would say I haven't made anything good enough to attract the attention of a spoilage organism :p )

So, you definitely do not need to pasteurize meads to have a stable product. Pasteurizing may change the flavor (in my case it might be an improvement ;) ) so your best bet to convince yourself may be to try it yourself. Make a batch of at least two gallons, split it apart, and pasteurize one. Then compare the results and see if you think it is worth it. It might surprise you. If you give it a go, post up the results here and let everyone know how it turned out.

I hope that helps.


12-11-2008, 12:01 AM
The thing that really gets me about pasteurization is that it only kills bugs once. After you're done pasteurizing, stuff can land in the mead and you're back to square one. So, what does this mean? Basic sanitization practice is the best way to keep your mead from spoiling--no extra filtration, chemicals, or heat needed. If you can keep the introduction of bugs to your mead to a minimum, the alcohol, low pH, and generally low nutrient conditions present in the mead will take care of the rest.

12-11-2008, 12:26 AM
Exactly right! There is no substitute for scrupulous cleaning, sanitization, and careful handling as you make, rack, age and bottle your mead.

12-12-2008, 02:59 PM

Thanks for the insightful reply. Just a little nervous about the potential problems after botting. magarcia12

12-12-2008, 02:59 PM
Wayne B. Thanks for the support. magarcia12

12-17-2008, 02:37 PM
Just my .02 worth, but also make sure that it's completely stabilized before bottleing. You mentioned settling so as long as the mead has been racked and stabilized, it should be quite clear.
I'll re-iterate on the sanitation. You can never be too careful.