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What does extra yeast do?

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you always should pitch the right number of cells for the job. there are plenty of yeast pitching calculators online. check them out.

 

if you were making a large quantity like 5 gallons of average strength beer, typically one sachet of yeast is enough. when you start making high gravity (strong) beers, it will require more yeast.  think of a large banquet table full of food. what happens if you only invite 3 ppl to feast and tell them to eat everything? eventually they crap out , explode, or just die. lol. yeast are like that.  kind of.

 

when you first pitch yeast, they take stock of the availability of food and their numbers. if numbers are sufficient they start eating and peeing out alcohol. if not, they start reproducing. when they reproduce they give off esters that can either benefit your beer or make ick flavors. also, if they have to stop to reproduce you cause lag time. it will take longer for fermentation to get rolling. this can be bad as it gives other critters lurking in the wort the opportunity to grow and multiply.

 

one yeast pack in a lbk is more than enough cells.

 

so short version: pitch healthy (reasonably fresh yeast) into the right temperature wort, and pitch the right amount for the job.

 

 

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Dry yeast pitched into a cool wort (70 deg F) have a fair chance of surviving. One sachet, about 2 grams of dry yeast, the number of live cells will quickly become sufficient to start active fermentation in a day or two for a small batch (2-5 gallons). Adding more yeast will not necessarily speed things up (lag time). The yeast need time to hydrate, and start metabolizing sugars, then they reproduce. You can find values on-line, I think the Screwy Brewer has it on his web site. 

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On 10/23/2018 at 11:45 PM, zorak1066 said:

one yeast pack in a lbk is more than enough cells.

so short version: pitch healthy (reasonably fresh yeast) into the right temperature wort, and pitch the right amount for the job.

 

 

Not sure what amount of yeast you are talking about when you suggest "one yeast packet".  Do you mean 1 packet of the included MRB yeast, or 1 packet of most standard size yeast packets (11gms)? 

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use a yeast calculator. if it says you need 11g of dry yeast and if mr beer yeast is only 5g in a pack..  add two.  i only used mr beer yeast for one kit then went to fermentis. no idea how many grams in a standard under the lid yeast pack.

 

i would save the mr beer yeast to boil as a sacrificial offering to the fermentis yeast. works as yeast nutrient.

 

 

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According to the 'Brewers Friend' on-line calculator, I pitched just enough (barely) of Safale US-05 into the 2.0 gallon LBK with a wort OG of 1.061 (using the MFG recommended pitch rate of +0.5 million cells per ml/degree plato).  I had pitched just about a 1/2+ packet, or roughly 6 grams of the yeast.  That's a very handy calculator indeed.

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1 minute ago, zorak1066 said:

use a yeast calculator. if it says you need 11g of dry yeast and if mr beer yeast is only 5g in a pack..  add two.  i only used mr beer yeast for one kit then went to fermentis. no idea how many grams in a standard under the lid yeast pack.

 

i would save the mr beer yeast to boil as a sacrificial offering to the fermentis yeast. works as yeast nutrient.

 

 

 

That's exactly what a few others on this forum have suggested.  I commented that I didn't know yeastie beasties were cannibals and would create yeasti beastie zombies.  ☺️

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under pitching is only a problem if the yeast are not very viable.. (old yeast = more dead cells), or if ester development is not a desired outcome. If you follow good sanitation practices, even a longer lag time will not typically be a problem.  the yeast will multiply and then eventually start doing their thing.

 

yep. yeast are cannibals. they are very fond of eating their dead.. and raisins... for some odd reason they love raisins. to make a yeast treat i boil old yeast, turn off the heat and cover. when the temp drops to about 165f i toss in a  handful of raisins (and/or an eigth of a  centrum silver vitamin)  and let it cool to room temp covered.  i do this on very high grav ale, high grav mead or wine, or when using very old yeast. i sometimes toss in a handful of grape nuts cereal too in a hop sock.. just dont ever boil it. when cool i toss the broth into the wort. ( you have to be careful about using a bit of vitamin tab because most have iodine in them, which can mess with cell development i think.)

 

100% not necessary. there is plenty of food in wort. again, i do it mainly for really high grav or with old yeast.  also with hobo wine. there is not a lot of nutrient value in sugar. with hobo wine you are using juice concentrates so no tanins, no peels, etc. nutrient bare.  i do step feedings because i noticed that the yeast dont like just sugar and burp out sulfur smells because they get stressed. my nutrient concoctions perk them right up and they get happy again.

 

the problem with feeding yeast goodies other than just wort is that they will tuck into the goodies first typically, which can create lag time.  you also have to be careful that anything you add that is not part of the beer recipe can contribute off flavors.  or you can just buy yeast nutrient. i like experimenting and am notoriously cheap.

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So if one was to have a rule of thumb based on the above ref to calculator and the 1/2 Safale pack, for average strength Mr. Beer LBK recipes, the Mr. B yeast pack of 5g is about right (surprise) when fresh. So this is also ~ equivalent to 1/2 a Safale 11g pack. 

With using 1/2 pack you get the potential issue though of saving the rest of the pack and having it be still good. I have been cavalier about the storage but I have had OK results with remaining 1/2 packs. So mostly I will put the whole 11g pack in. But I expect I should put them 1/2 packs in the freezer.

 

Rick says that the yeast can be lazy if over pitched - how much over pitching is needed to cause this?  Is 11g in an LBK ever going to do it? 

 

I do not remember having an issue with either 1/2 or full 11g pack. But I do not brew extreme beer.

I have used < 1/2 pack to make more flavored esters in wheat beer. 

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No, 11g in an LBK is not going to noticeably affect your beer.


Yes, Mr. Beer supplies the proper amount of yeast for 2.13 gallons of beer.

 

Yes, you can use an 11g packet of beer in an LBK.

 

The answer isn't the amount of yeast, the answer is the amount of yeast cells.  Unless you pull out a microscope and count yeast, you have no idea what number of cells are viable in the yeast you use.  I suspect not one person on this forum does this.

 

Most issues with yeast occur in a commercial brewery.  Why?  Because they have massive fermenters putting enormous weight (liquid wort) on top of a yeast cake, at the bottom of a tall fermenter that likely ends up in a cone.  And most commercial breweries use yeast for multiple generations.   If they are not careful, they can harvest weak cells that don't do well. 

 

With a Mr. Beer fermenter, there is a big surface with all the yeast spread out, and very little weight on it.  That's why there's no issue.

 

Here's one article on it - http://brulosophy.com/2016/11/07/yeast-pitch-rate-pt-5-underpitch-vs-overpitch-in-a-lager-exbeeriment-results/

 

There is a great book on yeast that is for those that are really, really, really into yeast (not me).  

 

Yeast: The Practical Guide to Beer Fermentation (Brewing Elements) by Chris White and Jamil Zainsheff  Chris White owns White Labs, one of the main purveyors of liquid yeast.

 

In fact, there is a whole series of books:

 

Water: A Comprehensive Guide for Brewers (Brewing Elements) by John Palmer and Colin Kaminski

 

Malt: A Practical Guide from Field to Brewhouse (Brewing Elements) by John Mallett 

 

For The Love of Hops: The Practical Guide to Aroma, Bitterness and the Culture of Hops (Brewing Elements) by Stan Hieronymus

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1 hour ago, RickBeer said:

 

 

Seconded, these are great books. 

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2 hours ago, Nickfixit said:

So if one was to have a rule of thumb based on the above ref to calculator and the 1/2 Safale pack, for average strength Mr. Beer LBK recipes, the Mr. B yeast pack of 5g is about right (surprise) when fresh. So this is also ~ equivalent to 1/2 a Safale 11g pack. 

With using 1/2 pack you get the potential issue though of saving the rest of the pack and having it be still good. I have been cavalier about the storage but I have had OK results with remaining 1/2 packs. So mostly I will put the whole 11g pack in. But I expect I should put them 1/2 packs in the freezer.

 

This why I only used 1/2 of the 11g Safale yeast in my 2 gal LBK experiment.  I didn't know how many grams the MRB packs were but going by the Safale website where they say 11g of their yeast makes 5-6 gals, I figured half of one pack would be sufficient for 2.1 gals.  And the yeast calculator on-line bore that out.  So,  now i have a half pack of the Safale and a full pack of the MRB left to do something with. 

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seal the safale pack. squeeze out any air. tape it shut. put it in a ziplock bag in the fridge. use it for your next small batch.. just dont wait half a year. re mrb yeast, we all know what i do with that. muahahahaha! PREPARE TO DIE!!!! (turns up stove to boil...listens to yeast cells screaming....)

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like me and rick said... feeding yeast is not necessary. they get plenty of food in the wort. even in high grav wort, if you pitch enough yeast you dont need to add a thing. i choose to do it as i mentioned above on special circumstances. the mr beer brewer should never have to worry about yeast nutrient or anything else complicated. the whole purpose behind mr beer is to make brewing simple.

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19 minutes ago, Mic Todd said:

Does anyone here know how much yeast is in the standard MRB packets under the lids, in terms of grams?  Thanks

just pitch the whole pack bro.....either a MRB pack or Safale pack

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6 hours ago, Mic Todd said:

Does anyone here know how much yeast is in the standard MRB packets under the lids, in terms of grams?  Thanks

I think the MB yeast is 5 or 5.5 grams designed for their 2 gal kits where the other yeasts like Safale etc. are for 5gal and 11g

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5 hours ago, Cato said:

I think the MB yeast is 5 or 5.5 grams designed for their 2 gal kits where the other yeasts like Safale etc. are for 5gal and 11g

 

That's what I was kinda thinking, because the packets don't say the weight and I have no way to weigh that small amount.  I ask because I now have two extra MRB yeast packets left over due to subbing with the US-05 in my last 2 experiments.  I may need them sometime.  Thanks

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On 10/27/2018 at 2:47 AM, zorak1066 said:

seal the safale pack. squeeze out any air. tape it shut. put it in a ziplock bag in the fridge. use it for your next small batch.. just dont wait half a year. re mrb yeast, we all know what i do with that. muahahahaha! PREPARE TO DIE!!!! (turns up stove to boil...listens to yeast cells screaming....)

 

Just what I did Z.  I used the remaining half yesterday when making my pumpkin beer because I didn't have any Safale S-33.  Fingers crossed.

(however, I did spare the lives of the MRB beasties, for now...)

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