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69*camaro
09-28-2006, 08:52 AM
Question; What are the advantages or disadvantages of maintaning a fermentation at the high end of the yeast tolerance or the converse? Does a slow fermentation produce a better product?

As always, your help is greatly appreciated.

MeadFan
09-28-2006, 11:09 AM
I don't know myself, but I did some searching in the forums for you. I would've asked that question in the future probably.

This post (http://www.gotmead.com/component/option,com_smf/Itemid,103/topic,2929.msg24546#msg24546) by Angus might help answer your question. Basically, what he says is that at high temperatures, more fusile alcohol is produced, which takes longer to age out, whereas cooler fermentation can be enjoyed earlier.

Oskaar
09-28-2006, 12:59 PM
Here's what I've found to be the case.

High temperature pros:
Shorter lag time, faster fermentation, quicker flocculation (some yeasts), quicker clearing (some yeasts), sometimes produces estery characters that are desireable but mostly not at higher temperatures.

High temperature cons:
Compromised yeast (higher cell mortality during rehydration and growth phase), production of fusel and other higher alcohols, undesirable estery flavors, undesireable phenolic flavors, slower flocculation, slower clearing, rocket fuel/gas-ahol character, higher production of SO2 and H2S, reduced expression of fruit and spice in melomels and metheglins, yeasty, and solvent like flavors, more suseptible to oxidation.

Low Temperature pros:
Slower more controlled fermentation, better flocculation, more complete and sometimes faster clearing, preservation of varietal honey characters, lowered risk of producing off flavors, better expression of fruit and spice in melomels and metheglins, more volume/mouthfeel in Traditional Meads, off flavors minimized, off aromas minimized, more elegant (structure and complexity) lower alcohol meads, less hot higher alcohol meads, and production of desireable esters (isoamyl acetate, hexyl acetate, phenyl ethyl acetate)

Low Temperature Cons:
Slower out of the gate to begin active fermentation, slower fermentation, stuck fermentation, incomplete fermentations, beneficial ester production, need higer levels of oxygen, subject to competitive wild yeasts due to slower start time, can be difficult to get the fermentation started.

Hope that helps,

Oskaar

69*camaro
09-29-2006, 11:43 AM
Thanks a lot. My future batches will ferment on the back porch. I have been using D47 and EC 1118 and fermentation temps in the 70 degree average.

Medsen Fey
12-13-2007, 11:26 AM
I hope it is okay that I am reviving this old thread. I was reading ssteufelhund's thread on saving a burnt mead (http://www.gotmead.com/index.php?option=com_smf&Itemid=412&topic=6181.msg50684;topicseen#msg50684), and I appreciated the amazingly thorough analysis of the mead posted by Oskaar. One of the key problems seems to have been fermentation at too high a temperature with the Montrachet yeast.

My question is which yeasts can ferment in higher temps (75-80) and produce the least amount of fusel alcohols and medicinal phenolic compounds? Some must be better than others. I have reviewed the various yeast charts and while they describe the temperature ranges of the yeast, they don't talk about the level of "off flavors" generated at the higher temps. Living in Florida, I only have so much space in the spare refrigerator, and some of my meads are being fermented at these ambient temperatures.

I have been watching (or to be precise - Reading) Sandman's Orange Blossom Yeast Test (http://www.gotmead.com/index.php?option=com_smf&Itemid=412&topic=5999.0) and have been quite interested in his results. Does anyone else have any thoughts on the best yeast for higher temp batches?

Happy Holidays!
Medsen

sandig
12-13-2007, 02:31 PM
From personal experience when I fermented meads this summer when it was hot (2 batches), both had some sort of yeast stress due to the higher temperatures. This created a rocket fuel taste (should fall out after a lot of aging--I hope). My winter meads (2 batches as well) have been very slow to ferment. The blueberry cyser stalled out a little early and I chose to keep it a dessert mead instead of struggling to get it going again in the cold. There are no off flavors and it was drinkable very quickly. The second, a cherry cyser, is still very slowly fermenting. I detect no off flavors but it is going really slowly (it is pretty cold here). I suspect this will also be drinkable a lot earlier.

Hope this helps
Sandi

Oskaar
12-13-2007, 06:09 PM
D21 is the only yeast I use in that temp range.

Cheers,

Oskaar

Medsen Fey
12-14-2007, 05:41 PM
I've read that Tokay yeast perform well at 80F. Has anyone had any experience with Tokay yeast?

wayneb
12-14-2007, 07:56 PM
I used to use "Tokay" yeast in the summers in my apartment in Houston, but that was over 25 years ago. I used it precisely for its compatibility with higher temperatures, since my other standard mead yeast at the time, Montrachet, produced burnt-plastic-smelling swill when the temperature in my apartment was above 80F.

But the Tokay yeast that I used is, at least according to my understanding, no longer available in the US. The manufacturer of that ADY was located in Hungary and as far as I am able to determine, no longer ships to North America. If there is a Tokay yeast available here again, I wonder if it is the same strain that I used so long ago.

Oskaar
12-14-2007, 08:57 PM
Try here (http://www.wijnmaken.nl/catalog/wijngist-kitzinger-tokay-p-1039.html?osCsid=19c55)

Cheers,

Oskaar

Medsen Fey
12-14-2007, 11:52 PM
Thanks for the information. Vierka's Tokay yeast (http://www.thegrape.net/browse.cfm/4,11398.htm)is available here in the U.S. and I may give it a try.

I saw in the yeast charts that DV10 has a very high temperature range for tolerance. Although my experience is quite limited, a few batches that I have done using DV10 with temperatures in the mid to upper 70s seem to have turned out well with essentially no "rocket fuel" or "medicinal" sensations. I don't know if others have found this to hold true.

In any case, I may need to ask santa for another fridge :icon_santa:

Medsen

wayneb
12-15-2007, 12:10 AM
A cautionary note when using Vierka yeasts. They are not ADY; instead they are dried grape skins, upon which are the yeast strains of interest. What that means is that you MUST make a starter and build up a healthy colony by first reehydrating the skins, and then pitching into a well aerated, "light" gravity must (say on the order of 1.050-1.060) to build that colony. If you just pitch a packet of Vierka into a full gravity must, if you're lucky you may see evidence of fermentation within a week or two. If you're unlucky, something else will grow in that must first, and you'll end up with an infected batch.

I routinely used to use Vierka mead yeast back in the day (mid 80's vintage), and my experience with starting a culture from their products helped me immensely when I cultured my own wild (or feral) yeast from my property earlier this year.

BTW - Thanks for the link to the Kitzinger yeast source, Oskaar! But I don't think I'll be ordering anything from the Netherlands anytime soon! :laughing7:

Medsen Fey
12-15-2007, 02:17 PM
Wayne,
Thanks for the advice on the Vierka yeast. When I try it, I will make sure to get a good starter going. Do you happen to know the alcohol tolerance of the Vierka Tokay?

I'd also like to ask the next obvious noob fermentation temp question. Which yeasts are the most notorious for producing off flavors/aromas at higher temps? Clearly Montrachet is right up there. Which others should be avoided if higher temp is an issue?

Thank you again,

Medsen

wayneb
12-15-2007, 08:28 PM
Not as a matter of record. Back when I used that yeast, the suppliers didn't routinely cite alcohol tolerance. But I do remember consistently getting 13-14% ABV results from it.

As far as the Lallemand yeasts go, I don't have any experience with them at higher temperatures, since I didn't use Lallemand yeasts until I moved up here to Colorado -- no problems with temps too high at 7500' altitude!

liff
12-15-2007, 08:34 PM
Madsen Fey,

You know what this sounds like to me? Us hot weather mead makers might want to do some batches this summer as a group brew. I am way new at this also and I'd like to share in the experience.

Liff

Oskaar
12-15-2007, 08:54 PM
71B, EC-1118, D47, CY3079, ICV-GRE, SIMI, Montrachet, Epernay II, have all, in my experience demonstrated a fairly high rate of fusel production at higher fermentation temperatures.

Hope that helps,

Oskaar

storm1969
12-15-2007, 09:39 PM
I can say that rc-212 seems to also demonstrate a fairly high rate of fusel production at higher fermentation temperatures.

teljkon
12-16-2007, 03:36 AM
Im in for that this summer there should be some good. Orange blossom around this summer. Hmm mead I can make outside my fridge whats this my iner childe is doing a big seasame streat yeah.
:happy10: