11 replies to this topic

[weave]

I finally got around to making that 1st mead today.I wasn't able to get into town to pick up yeast nutrients so I took Ewanzel's idea and used DME, assuming the DME would have the nutrients my yeast would need. I started by heating 1.5 gal of spring water on the stovetop. When it came to a boil I added 1lb-4oz of extra light DME that I had hanging around for yeast starters. Boiled the wort for 20 minutes, shut off the stove and added 1 gal refrigerated spring water. That got me down to 135F. Stirred in 16lbs of clover honey. Transferred to my fermenter and added enough spring water to get me 5.5 gal. Stirred and aerated. Got an OG of 1.102. Temp was 80F so I pitched 2 packets of EC-1118.My plan is to ferment out, sorbate, back sweeten with more clover honey, keg, and enjoy.What is the consensus on using DME in place of yeast nutrients? Did I do good? Huh, did I?And how vigorous is this thing going to ferment? Will I be needing a blowoff tube?

[Hightest]

DME is primarily a fermentable sugar (maltose), and IMO provides little in the way of the nutrients needed for an optimized mead fermentation - mainly a source of nitrogen. While there are other factors in play here, I suspect you may be in for a longer, slower, fermentation...

[weave]

You are the expert here. But my intuition is questioning this. Yeast thrive in DME, water, and hops mixtures. Please elaborate.

[ScottS]

Honey is almost completely devoid of nitrogen, so you need to add a lot of it to get a healthy fermentation. Yeast nutrients have a lot of concentrated nitrogen for exactly that reason.DME has nutrients, but in a much lower concentration. When you mix it up to beer wort strength, you end up with plenty. When you add a bit to a mead must, you are likely to fall far short of what is needed to sustain a 10 day fermentation.

[Hightest]

Scott's explanation clarify's my comment underscoring "...provides little in the way of the nutrients needed for an optimized mead fermentation" - the absence of sufficient supplemental nitrogen.

[weave]

Well. We'll see what happens from here.*crosses fingers*

[Hightest]

While my initial response was accurate, it was not sufficiently specific. After a short review of my references, I located the basis for that reply. What follows should be somewhat more substantive:The most critical fermentation yeast vitamin is biotin. It takes part in all major biochemical reactions that involve protein synthesis. Its deficiency is clearly shown by poor yeast growth and damaged plasma membranes (Yeast Technology, Reed and Nagodawithana).Reed and Nagodawithana document biotin levels in average beer wort of 0.56 micrograms/100ml, whereas in undiluted honey they were 0.066 micrograms/g - other vitamins were found to have similar levels (Nov/Dec 2005 Zymurgy, Ken Schramm, pg 22).So adding 4 oz of DME to 1.5 gal of water and boiling for 20 min reduces the mini-wort volume by evaporation - assume 18% leaving about 4655 ml. Using an avgerage beer wort biotin level of .56 micrograms/100ml yields a mead must biotin contribution of ~26 micrograms, which is added to a mead must of 5.5 gal (20,817ml).Adjusting the mini-wort biotin contribution to the total mead must volume results in a biotin level of ~ 0.125 micrograms/100ml - only about 22% of that found in an average beer wort.Using the DME did help to raise the overal biotin level, but not by a sufficient amount. Most importantly, it did little to offset the Free Amino Nitrogen (FAN) deficit found in honey - Clover honey FAN ~14ppm, optimum fermentation requires ~300 ppm.

[weave]

Good info. I am learning here.I added 1lb 4oz (20oz) not just 4oz. So that helps some. That gets me up to, what, 130 micrograms of biotin added? That gets me to .62 micrograms/100ml, right? Is my math correct? I am sure that is not optimum, but better than what you were assuming.When I get into work tomorrow I am gonna ask a few brewers/winemakers if they have any yeast nutrients I can use. Is this a situation of better late than never?

[Hightest]

...I added 1lb 4oz (20oz) not just 4oz. So that helps some. That gets me up to, what, 130 micrograms of biotin added? That gets me to .62 micrograms/100ml, right?

Not quite... The biotin correlation is based on "an average beer wort". That would mean a wort that was comprised of enough DME that is mixed with water to produce a typical wort volume somewhere near 5-6 gallons - usually that would require about 7 lbs of DME to achieve a OG near 1.045.In essence I gave you a credit by assuming that your DME /water mix would produce that "average wort" where actually 1¼ lb DME & 1.5 gal of water creates a SG near 1.029 meaning your DME addition added somewhat less biotin than I noted...

When I get into work tomorrow I am gonna ask a few brewers/winemakers if they have any yeast nutrients I can use. Is this a situation of better late than never?

It's not too late to add nutrients and DAP. What is the present SG? You said the OG was 1.102 @80°F - was that SG a temperature compensated SG?

[weave]

You said the OG was 1.102 @80°F - was that SG a temperature compensated SG?

Refractometer measurement.I'll have to sanitize a hydrometer and check current gravity. It is bubbling away right now.

[Hightest]

Refractometer measurement. I'll have to sanitize a hydrometer and check current gravity. It is bubbling away right now.

Ok, good to know. Do you know that you may also determine the present SG using your refractometer? My spreadsheet (in the FAQ) includes a method for doing so during fermentation. As such, I rarely use my hydrometer.