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View Full Version : Can you over "energize" your mead?



McJeff
10-09-2013, 09:52 PM
What is a standard amount you use per gallon?

McJeff
10-09-2013, 10:24 PM
My standard so far has been once each day for the first 3 days I add a teaspoon of nutrient and shake the piss outa it. Then I leave if alone for the rest of the month.

Chevette Girl
10-09-2013, 11:53 PM
I calculate my total intended amount (usually something like 1/2 tsp DAP and 1 tsp energizer per gallon), add 1/2 to 1/3 the energizer at pitch, 1/2 to 1/3 the nutrients s soon as there's airlock activity or the SG starts to drop, then I mix the rest of the nutrients and energizer for that batch together in a clean container and every time I go in to aerate, I give it a feeding, and I try to ration the feedings so that the last one is with the last aeration.

McJeff
10-10-2013, 05:17 AM
What's DAP?

Chevette Girl
10-10-2013, 07:04 AM
Diammonium phosphate, it's a nitrogen source for yeast but they can only use it in the first third or so of fermentation.

McJeff
10-10-2013, 08:57 AM
Do you see an advantage using it? Or a difference in the mead?

GntlKnigt1
10-10-2013, 09:25 AM
Yeast are much happier when properly fed, and work better and produce fewer fusels....
http://en.wikipedia.org/wiki/Fusel

McJeff
10-10-2013, 12:45 PM
I've just been using yeast nutrients and haven't felt like I had a problem.

Medsen Fey
10-10-2013, 12:46 PM
What exactly have you been using?



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McJeff
10-10-2013, 12:54 PM
Sorry meant to say yeast nutrients not energizer.

bernardsmith
10-10-2013, 12:55 PM
Diammonium phosphate, it's a nitrogen source for yeast but they can only use it in the first third or so of fermentation.

Why can yeast only use DAP in the early part of the fermentation process? Presumably we want to assist the yeast to reproduce during the early days after we pitch the yeast. In other words, we are willing to allow the yeast to expend MUCH of their time and energy in reproduction. They are going to be converting sugar into alcohol too but much of their energy is going to be used in dividing and reproducing. When the colony is large enough we want to inhibit reproduction and get the yeast to expend their energy in transforming the sugar into alcohol. My understanding is that if WE provide the phosphates later in the process the yeast will continue to expend more energy in reproduction than on eating (converting sugar to alcohol) . If we don't provide the phosphates then they don't have the nutrients they need to divide. In other words, it's not that the yeasts can't use DAP later. It's that we don't want them to. That's my understanding but I am not a chemist or microbiologist.... but you seem to have a different understanding.

McJeff
10-10-2013, 12:57 PM
. http://amzn.com/B0064H0MWY

Can you use too much nutrients?

Riverat
10-10-2013, 01:05 PM
. http://amzn.com/B0064H0MWY

Can you use too much nutrients?

You can indeed, anything not consumed by the yeast will remain as food for any spoilage organisms that may find there way in and survive the alcohol, you could even leave enough to taste but that would be using a lot.

anir dendroica
10-10-2013, 01:16 PM
My understanding is that the reproduction/fermentation cutoff for yeast is not defined by nutrient availability, but rather primarily by oxygen availability. Complete oxidation of sugar to CO2 (as occurs in the presence of oxygen) provides about 18-fold more energy (ATP) to the cell than conversion to ethanol. When oxygen is gone, the yeast ferment to survive but are unable to reproduce to any great degree, regardless of the amount of nitrogen available. They also lose the ability to utilize ammonium salts, though they can still make use of amino acid nitrogen.

The reason we aerate early on is to allow the yeast to reproduce rapidly, producing a large population of healthy cells for the fermentation phase.

As for using too much nutrients, of course it is possible. If you add more than the yeast can use, it just stays dissolved. DAP is salty, so with a serious overdose it could contribute an off flavor. It also remains available to other organisms, so if oxygen is introduced later excess nutrients will facilitate the growth of spoilage bacteria like acetobacter.

McJeff
10-10-2013, 01:35 PM
so my last 2 gallon batch i think i used 1 table spoon of nutrient, spread out over the first 3 days when i aerated it.

anir dendroica
10-10-2013, 02:58 PM
That sounds about right. I use generally 1/2 tsp DAP and 1/2 tsp Fermaid K (general nutrient/energizer) per gallon, which comes to 2 tsp or 2/3 Tbsp total per two gallons.

Worry not; mead is forgiving. Just don't start dumping in energizer by the cupful ;D

McJeff
10-10-2013, 03:51 PM
Ok cool ty guys, i didnt think i was goin overboard. But was just curious what would happen if i did use too much.

bernardsmith
10-10-2013, 09:04 PM
Thanks for that information Anir. When I make fruit wines I add about 1/2 of the total nutrients as I pitch the yeast and the second half after three or four days when the SG has dropped about 040. I have only made a few batches of mead and I have been using the same technique.

anir dendroica
10-10-2013, 11:27 PM
I usually front load it a bit more, 40% at pitch, 40% one day later and 20% at the 1/3 break about 2-3 days later. I think adding half at the 1/3 break might risk nutrient stress on day 3 or so, but I haven't done experiments to say for sure.