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delinden
06-09-2011, 05:46 PM
Hi!

10 days ago I started two small batches of mead:

- 1800 grams of pollen honey, 3,3 liters of water, one tsp yeast nutrient and half a pack of EC1118. Brix 29,5, to 13 as of yesterday.

The other was similar, only difference was 3 liters of water and adding a large tsp of cinnamon, ginger, cardamom, and a large tbsp black tea. Brix 32, to 17 as of yesterday.

Yesterday I racked and filtered them, since the fermentation had almost stopped. I added a tsp of yeast nutrient to each, and another half pack of EC1118. It hasnīt really taken off again yet, only a blop every 4 minutes or so.

the meads are quite sweet still, but also a bit hot. I would like it to go more dry, hence the EC118. I suppose the alcohol of about 14-15% by vol is slowing down the yeast, so what can I do to make as nice an environment as possible for it?

Also, when the mead is dry(sweet) to my taste, I was thinking about halting the fermentation using brandy for fortification. Is this a good idea, should I use some other stuff first or instead?

the end result, I imagine and hope, should be a semi sweet, strong fortified mead that age well, as Im planning to make two or three bottles of each and put them away for a year or so...the rest Iīll enjoy with some ice cream or something. At this stage the flavors of them both are already much, much better than my earlier attempts, so Im getting my hopes up already.-)

Advice is much appreciated!

akueck
06-09-2011, 07:56 PM
Fortifying with brandy to kill the fermentation is definitely possible. However, you might need to add quite a bit of it to get the alcohol up high enough. A good rule of thumb is around 20% abv in the finished solution will be enough to stop all life. :) If your brandy is 40% abv and your mead is 10% (for easy numbers), you'd need to add 0.5 L of brandy to every 1.0 L of mead to get to a total of 20% abv. If you use something like everclear which is up to 90-something% abv, you'd be able to use a lot less to fortify the mead.

Are you using a refractometer or hydrometer? If a refractometer, are your Brix readings corrected for alcohol content? If not, the actual amount of sugar in your mead is a lot less than you think. You can search around for a refractometer calculator to convert to the real density.

delinden
06-10-2011, 06:00 PM
Fortifying with brandy to kill the fermentation is definitely possible. However, you might need to add quite a bit of it to get the alcohol up high enough. A good rule of thumb is around 20% abv in the finished solution will be enough to stop all life. :) If your brandy is 40% abv and your mead is 10% (for easy numbers), you'd need to add 0.5 L of brandy to every 1.0 L of mead to get to a total of 20% abv. If you use something like everclear which is up to 90-something% abv, you'd be able to use a lot less to fortify the mead.

Are you using a refractometer or hydrometer? If a refractometer, are your Brix readings corrected for alcohol content? If not, the actual amount of sugar in your mead is a lot less than you think. You can search around for a refractometer calculator to convert to the real density.

So 20%ABV is the minimum to ensure no further fermentation? the EC1118 yeast is said to tolerate 18, but I would suppose there is a grey zone above this, where there may be some activity still. I guess Iīll experiment a bit with brandy, but iīd rather not have too much color or flavor added to it, so Iīll also give everclear a try. Here in DK the equivalent is 96%ABV but expensive as hell, so I was thinking about experiment on "refining" some 50%ABV vanilla extract I have, on some swedish column equipment I have. If all fails Iīll just go with vodka, but any suggestions are much welcomed.

I use a refractometer, and have put in the values in a spreadsheet that should correct for alcohol...but you have a good point, posting the raw readings donīt make much sense in itself:-). According to my spreadsheet, the ABV ranges between 14,5 to 16 and 13 to 15 respectively, depending on the algorithm used(the spreadsheet displays results from several other wine/beer calculators). But having made a few apple wines with EC1118, I know what a bone dry wine tastes like, Iīm quite sure thereīs still a lot of sugar left;D

tweak'e
06-11-2011, 12:12 AM
Hi!

10 days ago I started two small batches of mead:

- 1800 grams of pollen honey, 3,3 liters of water, one tsp yeast nutrient and half a pack of EC1118. Brix 29,5, to 13 as of yesterday.

The other was similar, only difference was 3 liters of water and adding a large tsp of cinnamon, ginger, cardamom, and a large tbsp black tea. Brix 32, to 17 as of yesterday.

Yesterday I racked and filtered them, since the fermentation had almost stopped. I added a tsp of yeast nutrient to each, and another half pack of EC1118. It hasnīt really taken off again yet, only a blop every 4 minutes or so.

the meads are quite sweet still, but also a bit hot. I would like it to go more dry, hence the EC118. I suppose the alcohol of about 14-15% by vol is slowing down the yeast, so what can I do to make as nice an environment as possible for it?


what temp is the must at?

yeast will slow right down when they get near the end. it can take just as long to ferment the last little bit as it did all the rest. best thing here would be to simply leave it alone.
if its taken 10 days to do the first part i suspect it was rather cold or stressed for some other reason. i would allow at least another 10 days for it to finish, it may take longer.
i don't think there was any reason to filter and repitch.

unfortunately adding the extra nutrient might cause problems as you already had an overly large amount to start with.
what yeast nutrient are you using?

i've got a batch at the moment using ec-1118 thats doing similar speed, thats simply because its so darn cold out in the shed.

delinden
06-11-2011, 08:26 AM
what temp is the must at?

yeast will slow right down when they get near the end. it can take just as long to ferment the last little bit as it did all the rest. best thing here would be to simply leave it alone.
if its taken 10 days to do the first part i suspect it was rather cold or stressed for some other reason. i would allow at least another 10 days for it to finish, it may take longer.
i don't think there was any reason to filter and repitch.

unfortunately adding the extra nutrient might cause problems as you already had an overly large amount to start with.
what yeast nutrient are you using?

i've got a batch at the moment using ec-1118 thats doing similar speed, thats simply because its so darn cold out in the shed.

Well, the temp is 72 to 75, so that should not be a problem. I guess it could be a bit stressed as I took the yeast straight out of the freezer and dumped it in. Could be a good idea to begin using starters instead?

The filtering was mostly because of the spice "hat" that had formed started to look a little funky, and also I decided it was spicy enough at that point. And I had hoped that some fresh yeast could speed things up a bit.

As of now itīs sitting peacefully with same slow activity going, a blop every 3 minutes or so. I think Iīll go with your advice and just leave it alone for a bit:-).

About the nutrient, Iīm not really sure. Itīs a standard winemakers nutrient, apparantly itīs called "EMOVIT". It smells nasty, like when eating a kids vitamin pill. I sure hope it doesnīt carry over too much:eek:

kudapucat
06-11-2011, 09:02 AM
Freezer?? With wine yeast?
If any is still alive after being frozen, then they'll be a bit stressed. Then tossing them into 75 F must would shock the bejeebers out of them.
Yeast are your friend. Play nice. Do unto thy neighbour and all that.
From 0 F to 75F is a huge difference.

akueck
06-11-2011, 11:56 AM
You can freeze the dry yeast packs, that is fine. I keep mine in the fridge. I would still recommend rehydrating the yeast (usually there are directions on the package) before dumping them in your must.

Vitamin pill nutrient sounds about right. Vit B pills usually contain a good bit of yeast extract, which is what nutrients also contain. Same stuff, same smell. ;)

If your mead is at 14% or so, adding more yeast now is not going to do much. If it firmly sticks here, you can look up "restart protocol" and find ways of introducing a new yeast pitch that won't immediately die in the high-alcohol environment.

You can usually find 100-proof vodka, which will get you more mileage than the 80-proof stuff at least. Everclear is expensive, but at least you won't need much of it. If you need to add something lower proof, it could be fun to experiment with a few different liquors and see what the taste contribution is.

20% abv is a pretty safe spot. Most port, sherry, etc is in the 18-21% range and survives just fine. If there is a lot of sugar in there too (high sugar is also a preservative, and by "high" I mean upwards of 20% sugar by weight in the presence of 15% alcohol), it can go even lower in alcohol. Flavored liqueurs are often around 15% abv and full of sugar, and they keep forever.

kudapucat
06-11-2011, 12:39 PM
You can freeze the dry yeast packs, that is fine. I keep mine in the fridge. I would still recommend rehydrating the yeast (usually there are directions on the package) before dumping them in your must.

Really?
Everybody I know has always said 'never freeze brewing yeast'
I also thought I saw a 'store at 4C' written on a packet.
I always wondered why bread yeast was hardier and could handle being frozen.
I know that, for one: if DW got ahold of the idea that my yeast need not be kept in the fridge, I could have some real trouble on my hands.

tweak'e
06-11-2011, 07:32 PM
Well, the temp is 72 to 75, so that should not be a problem. I guess it could be a bit stressed as I took the yeast straight out of the freezer and dumped it in. Could be a good idea to begin using starters instead?

About the nutrient, Iīm not really sure. Itīs a standard winemakers nutrient, apparantly itīs called "EMOVIT". It smells nasty, like when eating a kids vitamin pill. I sure hope it doesnīt carry over too much:eek:

temp is fine for fermenting. little bit on the hot side for good tastes. its going to take a while to age.

yeast straight out of the freezer and into must is a shocker alright. always let it warm up to match must temp. let it defrost first !

the nutrient sounds like energizer. trouble is the terms are all mixed up. sounds like you have the vitamin mix. possible no or little nitrogen in it. need to get some DAP for it. 1/2tsp would be plenty. probably a bit late to add anything anyway but i doubt it will hurt.

otherwise just leave them and start another ;D

akueck
06-12-2011, 12:10 AM
Really?
Everybody I know has always said 'never freeze brewing yeast'
I also thought I saw a 'store at 4C' written on a packet.
I always wondered why bread yeast was hardier and could handle being frozen.
I know that, for one: if DW got ahold of the idea that my yeast need not be kept in the fridge, I could have some real trouble on my hands.

I'd rather store it in the fridge, but I've heard of storage in the freezer turning out fine. They're basically freeze-dried as it is, so being a little colder isn't so bad. Now, if the pack has been opened, storing in the freezer is probably a lot worse due to condensation.

kudapucat
06-12-2011, 12:41 AM
Ah condensation. I didn't think of that. I always use big bags... A pound or so. So maybe that's why I was told such, abd I'm confused.

Medsen Fey
06-13-2011, 12:15 PM
Really?
Everybody I know has always said 'never freeze brewing yeast'
I also thought I saw a 'store at 4C' written on a packet.


You weren't imagining things. It used to be that freezing wine yeast was not recommended, but they've decided it is OK now.

Per the Lalvin yeast FAQ (http://www.lalvinyeast.com/freezing_Dried_Yeast.asp):




Freezing dried yeast

......................................
I have always frozen my dried yeasts after purchase and before use. I Have not noticed any detriment to the final product, but I seem to remember reading somewhere in that past year or so not to freeze dry yeast, perhaps even on a package. Is it acceptable to freeze dry yeast or is there some detriment to the practice?
Cheers,
Mike Dixon

Mike,
You are right; we had stated in our old technical data sheet that dry yeast should not be frozen. However in the last 3 years we had a project running to optimize storage conditions for dried yeast. We stored several lots of vacuum packed dried yeast at room temperature, in a refrigerator and in a freezer and determined viability, vitality and fermentation performance every 3 month for two years. The results indicated that freezing the yeast does not harm the yeast but is even better than storing the yeast at room temperature. BUT for all storage temperatures it is very important that the yeast is still vacuum sealed. Air/oxygen is doing more damage to the yeast than any difference in storage temperature.
Regards
Forbes & Tobias




Storage of dry yeast

......................................
From: William Frazier
I've purchased a 500 gram quantity of wine yeast. This is more than I will use for winemaking this season. Can this yeast be stored for future use? If so, what would be the best conditions?

Response from Dr. Clayton Cone:
Active Dry Yeast, at <5% moisture, is originally packaged in an oxygen free atmosphere either via nitrogen flush or vacuum. Under these conditions they will loose about 20% activity / year when stored at 20C.(68F) and about 5% activity / year when stored at 4C.(40F). It is the presence of Oxygen and the pick up of small amounts of moisture that causes the yeast to deteriorate at a faster rate, once the package has been opened. If you can vacuum pack(kitchen vacuum package equipment)or store in an air tight container and refrigerate you may retain a substantial amount of the activity. It would be wise to increase the inoculum 50% to be on the safe side. It is always a gamble, depending on how much moisture the cells have picked up each time you open and close the package and return to the refrigerator.

kudapucat
06-13-2011, 09:05 PM
Thanks Medsen.
I cut my 500g blocks into 100g and vac seal them, then open and revac seal one at a time. I guess I'll buy another when this one stops working :rolleyes:
either way, 500g gives me 100 batches or so, but only cost 10 times what a 5g packet does, so I've made my money back already, my yeast is now effectively free 8) So I can afford to double innoculate, and I often do put heavy teaspoons of yeast in, just cos I can afford to be flippant.