Zinc

[JoeV]

What forms of Zinc is everyone using for supplementing wort? It seems as though ZnSO4 7 h20 is the most common. What about zinc acetate, or zinc chloride, or zinc citrate, or zinc gluconate. Anyone using any of the other (USP) forms of zinc with success? I would really like to go with acetate or citrate as I would imagine them to be more soluable than sulfate but I don't really know if its a problem in the ammounts needed for suplementation.

[gitchegumee]

I don't use any supplements and never have. I don't see any reason to. Does anybody know of any solid reason that their yeast must have supplemental anything to ferment completely, flocculate properly, and repitch successfully? What yeast is it? Does it matter? Is your wort mineral deficient? Just curious why these supplements have such a following.

[monkeybrewer]

nutrients

I use Wyeast 1056 and never use nutrient supplements...I ferment in 2.5 days and have great floc and no flavor or filtration difference after 25 generations...I did use a common english yeast strain at the last place I worked as it did need some help in the form of a supplement to stay consistent over a handful of generations. I think some strains may need some help, others are surely fine with out.
Cheers

[GlacierBrewing]

The only zinc I've used was included in Brewer's Choice™ Wyeast Nutrient Blend.
I experimented with this product by using the recommended dosage on one batch then nothing on the next, on and off with the same yeast strain and generations. I did not notice any perceivable improvement on my fermentations. Not to say this product didn't work, but my brews may not benefit from it.
Why are you needing to add zinc to your batches?
Dave

[dick murton]

Zinc sulphate and chloride are widely used. I've never heard of other forms being used, but perhaps this is simply because they are more expensive. If you are brewing in stainless vessels, and repitching a number of times, then you may find the yeast viablitiy drops, and attenuation is not as good in later generations. It seems to vary form yeast strain to yeast strain, and with increasing generation numbers.

If using copper kit, the copper sometimes contains sufficient zinc as an impurity not to need to add extra - though probably modern copper is much purer than it was 50 or 100 years ago.

Typical addition rates 0.1 to 0.3 ppm of zinc. Both chloride and suphate forms are very soluble

Cheers

[Woolsocks]

I used Kerry Yeastex every batch for a while, then decided to try not using it to see what happened. I expected that in all-malt brewing with a robust yeast (Fermentis US-05, supposedly same as WY1056/WL1) Not good results. Beer fermented quickly but required a long diacetyl rest and just didn't taste right -- no specific off-flavors but it didn't taste right. Subsequent pitch was worse -- beer really off, very long fermentation, even though I used yeastex on the 2nd pitch. Dumped yeast and started fresh.

My theory is that with my wort composition and yeast strain, the yeast probably benefits from some amino acid in the yeast nutrient (does Yeastex contain valine? -- that would explain long diacetyl rest)

See also http://www.probrewer.com/vbulletin/s...ad.php?p=29790

[gitchegumee]

Interesting notes Woolsocks. My beers are quite dry, finishing as low as 1.4P for our Light beer. I will try nutrients in a few batches soon to see whether I can gain better FG consistencies--especially repitching. Our water supply is nearly devoid of minerals and perhaps yeast nutrients will get me something. Nothing vetured, nothing gained. Sounds like every brewery is different. Matt, any comments on your former brewery?

[matt]

In "Paridise" I was mostly repitching new yeast every batch. (dry yeast) Had a hard time to get fresh yeast there. Had one batch that was "off". blamed that on unhappy yeast. (under pitched?, Low O2?, Temp?)
I believed it was changed, but when we lost power, every for a second, which I'm sure still happens there, everything failed in the off/shut position. Cooling being the critical one. so my yeast was not always treated with the respect it should have been.
If using nutrients, I use wyeast yeast nutrients when propogated fresh yeast and in the later generations of my yeast. It seems to help the older yeast, so I can get 1 or 2 more generations out of it. (faster fermentations, etc)

[Brandes]

After several uses of zinc, do the yeast start to become addict?

[brewbonghm]

I frequently will go to the health food store and buy chelated zinc when I feel like I'm getting a cold. It usually costs about $2 for a hundred chalky tasting 50mg tablets. By the above calcs this should treat 170-500l of wort for fermentation. I've never fed it to yeast but it always makes me feel better, and has never made me "jones" for more.

[Bainbridge]

Resurrecting an old thread.

So I'm tired of paying for yeast nutrient just to get the zinc in it, since we are really low on that but we've got plenty of FAN in our worts. I was crunching some numbers to see if using Zinc Sulfate Heptahydrate would be more cost effective. Been a while since high school chem though, so here's how I've worked it out. Sound right?

We are going for 0.3ppm Zn+ per hectoliter. The formula weight for ZnSO4 7H20 is listed as 287.54.

So:

0.3 mg/L * 1000 L * mol weight ZnSO4*7H20/Zn+

which when converted is

0.3 mg/L * 1000 L * (287.54/65.38)

= 1,319.39 mg per hectoliter, which is about 15.5g per bbl.

That sound about right? Because if so, enough Zn for a 10bbl batch this way would cost about $2 vs. about $4 for yeast nutrient.

[liammckenna]

Resurrecting an old thread.

So I'm tired of paying for yeast nutrient just to get the zinc in it, since we are really low on that but we've got plenty of FAN in our worts. I was crunching some numbers to see if using Zinc Sulfate Heptahydrate would be more cost effective. Been a while since high school chem though, so here's how I've worked it out. Sound right?

We are going for 0.3ppm Zn+ per hectoliter. The formula weight for ZnSO4 7H20 is listed as 287.54.

So:

0.3 mg/L * 1000 L * mol weight ZnSO4*7H20/Zn+

which when converted is

0.3 mg/L * 1000 L * (287.54/65.38)

= 1,319.39 mg per hectoliter, which is about 15.5g per bbl.

That sound about right? Because if so, enough Zn for a 10bbl batch this way would cost about $2 vs. about $4 for yeast nutrient.

No, it doesn't sound right.

.3mg/L x 1000L = 300 mg elemental Zinc in total for a 10 hl batch

Try adding 5 or 6 of 50 mg Zinc supplement tabs from your local chemist/pharmacy/drug store to the boil.

You may also want to try what we do: we use a half pint of spent yeast into our brewkettle each batch as a source of some trace nutrients for the next generation of yeast. Our water is virtually devoid of any minerals, naturally, I might add, not softened by the regional municipality.

Good luck,

Pax

[Bainbridge]

Hmm well let's check again. Let there be math!

0.3 mg/L x 100L = 30 mg/hL (30 mg per hectoliter is .3 parts per million)
30 mg/hL x 1.17 hL/bbl x 10 bbls = 351 mg/10bbl (converting to barrels and then to 10bbl batch, so we need 351 mg Zinc per 10 bbls)

But we've got Zinc Sulphate, Heptahydrate to work with. So for every zinc there's a SO4 and seven waters. So we need the gravimetric factor, which is the weight of the full mineral mix divided by the atomic weight of zinc. So 287.54/65.38 or 4.398.

To get our ppm we are looking at:

grams ZnSO4 7H20 to measure = (desired ppm x desired volume in L (i.e. 10bbl converted to L) x gravimetric factor) / 1000 to make it ppm

or

(0.3 x 1173.48 L x 4.398) / 1000 = 1.548 gm total ZnSO4 7H20.

Which, if you divide 1.548 by the gravimetric factor of 4.398 you get 351.97 mg Zinc, just like we calculated we need above. Whew!

And looking back, it looks like I did the wrong conversion to hL in the first post and did kiloliters (because derp), which threw the mess off by a factor of 10. So if that's right, a dose of ZnSO4 7H20 is like 20 cents.

Yeah we have pretty soft water here too, mostly rainfall. So I add things back in. It is tempting to chuck a cupfull of yeast in whirlpool though, get some aminos and whatnot in there. Cheaper than buying yeast nutrient anyway.

[Bainbridge]

I just picked some up from a chem supply company on Amazon. 500gm was like $37. Given the above calculations even rounding up to two grams ZnSO4*7H20 I'll get 250 10bbl batches out of this bottle, so that's $0.15 a batch.

But somehow I suspect Free State will be needing a whole lot more than a half kilo Steve...

[Bainbridge]

Quite right!

I don't have zinc numbers for my particular water (Ward Labs doesn't include Zinc in their brewing water test) but based on the most recent report for Seattle's public supply, we have approximately the same water just a few miles away here on the island (~1ppm Sulfate, ~20ppm Calcium, etc.). Interestingly we have significantly more sodium (28 vs 1) and chloride (18 vs 3). Sitting in the middle of Puget Sound, it's not surprising we have a little more salt in our water! But I would imagine that our elemental zinc is similar. Seattle is listed as 0.8U, which I understand to be under the measurable threshold of 0.8 ug/L, (if I read the report right, it's a bit vague about its units). But that would be, basically, almost no zinc other than what you're going to get from your pipes.

So adding 0.3 mg/L (as calculated above to be about 1.5gm ZnSO4*7H20 in 10bbls) would be 300 ug/L. Found a report by the WHO on zinc in drinking water, which places the organoleptic threshold at around 3 mg/L, so at 0.3 we'd be well under it.