View Full Version : long fermentation... thoughts?

09-05-2005, 12:46 AM
I'm curious if anyone has messed around w/ extending the fermentation process on a mead? I've currently started a batch, extremely sweet (1.17), and am planning on adding water down the road and re airating close to the end of "first" fermentation. The addition of water would knock down the %abv and allow fermentation on remaining sugars to continue?

09-06-2005, 07:37 AM
Im new to this as well but my understanding is yeast dies at a certain %. I guess by allowing it not to ferment over that certain % and diluting it to a lower % the yeast should continue to ferment the rest of the sugar in your mead. Id just like to know why one would wish to extend a fermentation? If you like your mead a certain way why not get the sugar levels right at the beginning to allow the fermentation under co2 apposed to adding more oxygen when you dilute the batch. I guess it depends if you like your mead sweet or a little sweet moving through to dry.

Id like to know of benefits to a prolonged fermentation if anyone can shed some light.


09-06-2005, 08:57 AM
What are you goals for using this process? I'm pretty new to mead, but from what I've read this would produce a stale mead with other compounds you'd rather not have in your mead, due to restressing your yeast.

Now I have heard of reairating your must in 24 hours, but it is still in the first stage of fermentation (the lag, multiplying, nutrient stock of stage). I could understand if you wanted to add more sugars to your racking and you wanted to strengthen your yeast (ones with a higher abv tolerance). However, I'd have to agree with Mu when it comes to a lower alcohol goal. If you're looking more to condition your mead longer before bottling, I think oxygen will queer your process.

09-06-2005, 12:19 PM
Extending the fermentation will lead to yeast stress, higher alcohols (fusels), H2S, SO2, and other off-flavors that will take a very long time to age out of your mead, if they age out at all.

A good healthy fermentation with adequate nutrients and nutrient supplements either in fruit or powdered form is your best bet for a good mead.


09-07-2005, 01:21 AM
The more I've read about this, the less I wanna do it. I didn't really have a plan other than the must ended up way sweeter than I had planned, and I don't have the storage capasity to increase at this point. I'm thinking I'll just leave it as a sickening sweet 2gal batch.

09-07-2005, 02:13 AM
How about you post your exact recipe complete with beginning gravity and current gravity and we pony up some ideas to save your investment?

Usually you can save a batch with a little help and some good ideas.

Let us know,


09-07-2005, 03:05 AM
Its not to late to dilute and repitch. You can always incrementally feed and sweeten til you have the alcohol level you want then sweeten at the end. This is generally a more reliable method and yeilds better results

09-07-2005, 06:14 AM
If he's still in the initial fermentation heres what I'd do, fill a carboy about 1/5th full of water, rack into the secondary, stir gently... but do not aerate. My honey maple mead was made this way and it scored 89 out of 100 at a SCA competition. Documentation and Presentation were the only areas I had points docked. A perfect 10 in Color & Clarity, 10 in Aroma, 10 in Bouquet, 10 in Acid, 10 in Tannin, 10 in Sweetness (appropriate to type), 10 in Alcohol, 10 in body & finish. My racking onto water was about 3 months into the fermentation process and it was my second racking of the mead. No need to re-pitch if there is any fermentation still active.


09-07-2005, 11:56 AM
There are concerns with diluting, re-aerating and/ or re-pitching:
-Stressing the yeasts can lead to off flavors or poorly developed lipid layers in the cell wall (reducing alcohol tolerance and promoting premature cell lysis).
-When diluting the must, sugar is not the only nutrient to consider. Nitrogen sources, vitamins and other growth factors can become limiting…Especially if you have already gone through a partial or full primary fermentation. Again, this will lead to stress.
-It takes a period of time for cell mechanisms to adjust to changes in culture conditions. Switching back to aerobic conditions after the yeast have geared up for the anaerobic fermentation cycle can waste a lot of cell energy and nutrients (in addition to causing stress and off flavors).

In general, it is good idea to give your bugs all that they need (nutrients and growth conditions) and allow them to go through a nice, natural fermentation process with little or no interruption. Under these conditions, you can be assured that your yeast will perform as advertised in terms of alcohol tolerance and flavor characteristics. However, if you don’t have a “perfect” fermentation it does not mean all is lost. Depending on your recipe, you may have components that will mask off flavors (fruits, spices, beef jerky, etc.). Also, you may generate off flavors that you find appealing (i.e. some people like a lot esters, others do not). As Oskaar mentioned above, post your recipe and original readings…There are many experienced brewers here that can offer good advice.

Personally, if I had a mead that was too sweet I would combine it with an overly dry batch to balance out the flavor before I would try to dilute/ re-pitch.


09-07-2005, 08:21 PM
I've currently started a batch, extremely sweet (1.17), and am planning on adding water down the road and re airating close to the end of "first" fermentation.

He sounds to be very early into fermentation (less than 2 weeks?) Nutrients would be a good idea if he hasn't added any... they will help the yeast convert more of the sugars, but I doubt the yeasts are even close to being stressed this early(except for the stress of a high gravity).

Without nutrients he would be in for a very long fermentation. If he had added nutrients and the heat was in the high 70s to 80s then the yeast might have brought the ABV high enough and the nutrients low enough to stress the yeast. In any case... in my mind the only thing diluting would do at this point is lower the stress on the yeast by lowering the gravity and Alcohol %. IMHO it would be best to add the water while the batch is still very young. A definite no on late aeration though.

Excerpt from a paper on High gravity brewing - This environment (high gravity) can leave even the most resilient yeast more susceptible to infection, mutation, and damage. Inhibiting growth factors, yeast stress and subsequent fermentation problems.

Taking the above into account... it is my belief that the easiest way to relieve stress in a high gravity environment is to dilute as soon as possible, taking efforts to minimize aeration. Doing so will return the environment to a more acceptable range for the yeast, they in turn will be healthier & happier for the remaining duration of the fermentation.

In response to - When diluting the must, sugar is not the only nutrient to consider. Nitrogen sources, vitamins and other growth factors can become limiting. - True... to a point, but not noticeably more than if the mead had originally been started at a lower gravity (if it's still early into the primary fermentation)

I do believe fermaid K would be an excellent addition if diluting at this point though.


09-08-2005, 01:32 PM
You could also consider adding yeast hulls.

From Scott Labs <a href="http://www.scottlaboratories.com/products/fermentation/nutrients.asp#YeastBase">website</a>:

Inactive yeast hulls are a preparation of the insoluble fraction of whole yeast cells (i.e. cell wall membranes). A number of publications have cited the effectiveness of yeast hulls in the prevention of sluggish and stuck fermentations. Yeast hulls added to the must serve to supplement survival factors such as sterols, to increase the surface area of clarified juice, and to absorb toxic compounds.

09-08-2005, 04:22 PM
My main issue is a lack of a secondary to rack into at the moment. I thought I had it timed out properly that I could be bottling my current batch approaching completion. I didn't want to let the fruit I had go bad at the same time, and I do have 2 - 1gal bottles. So what I've done is basically made a 2 Gal batch with the amount of sugar for a 5Gal batch.

6lb fresh sliced apples
10lb honey
1 jar (16 oz) apple butter
1/2tsp tannin
Wyeast nutrient
1 stick cinnamon
red star cote des blancs yeast

Added in that order and airated w/ wisk (all I got heh, I live in a school dorm :p )
Starting SG 1.17, current unknown
8 days into primary
Bubbling regularly and without assistance. The thought on reairating were taken from reading one of oskaar's posts where he mentioned airation at the very end of fermentation could be helpful.

09-08-2005, 05:09 PM
A 5 gallon batch would finish extra dry using that yeast. Can you get ahold of a 3 gallon carboy at your local brew shop? That recipe would be just about perfect for a 3 gallon batch.


09-09-2005, 12:57 PM
Ohh.... One thing I neglected to mention above, I filled w/ purified water (upstate NY water SUCKS) to 2.2 gallons after the honey, mixed then added the other ingredients. So since the apples were added after that, it is quite possably at 3 gallons right now. Lastly, it's currently sitting in one of my two 6.5G fermenting buckets.

09-09-2005, 01:35 PM
Ah, I misread... at first glance it seemed you had it in two 1 gallon jugs.

09-14-2005, 11:06 PM
still bubblin ;D (barely over 2 weeks now though)