Is it worth doing

[MrRook]

An all-grain wort doesn't need nutrient.
I only use it on worts that are all extract or use extracts for a substantial portion or are high gravity.

 

[Braufather]

An all-grain wort doesn't need nutrient.
I only use it on worts that are all extract or use extracts for a substantial portion or are high gravity.

Just cam across this thread whilst searching the topic. The is an ipa feature in a2015 copy of BYO magazine with a few award winning recipes (all grain). Some use yeast nutrients some don’t. Not sure what why, maybe just personal preference?

 

[strange-steve]

An all-grain wort doesn't need nutrient.

There's a few comments like this, however one thing that isn't provided by malt that yeast needs is zinc. So it can be helpful, particularly for starters, to add a small amount of zinc containing nutrient to help yeast growth. Only a tiny amount of zinc is required, something like 200 ppb, and it may not have a noticeable effect in the finished product, but I personally think it's a good idea to look after the yeast as best you can. So to answer the OP, it might be worth doing, especially in high gravity worts, but it's not a necessity.

The diamonium phosphate, wine type nutrients are pointless in beer though because there's no zinc in them.

 

[Gunge]

The diamonium phosphate, wine type nutrients are pointless in beer though because there's no zinc in them.

So wine yeast doesn't need zinc but beer yeast does - how so? All I can think of is that grapes and other fruits contain the zinc not present in beer ingredients.... right?

 

[strange-steve]

So wine yeast doesn't need zinc but beer yeast does - how so? All I can think of is that grapes and other fruits contain the zinc not present in beer ingredients.... right?

Wine yeast nutrient adds things which are much more important for good yeast health than zinc, but in beer those things come from the malt making it a pointless addition. Yeast will ferment without zinc, but it's beneficial for growth, and afaik most fruits do contain a small amount of zinc.

 

[BeerCat]

There's a few comments like this, however one thing that isn't provided by malt that yeast needs is zinc. So it can be helpful, particularly for starters, to add a small amount of zinc containing nutrient to help yeast growth. Only a tiny amount of zinc is required, something like 200 ppb, and it may not have a noticeable effect in the finished product, but I personally think it's a good idea to look after the yeast as best you can. So to answer the OP, it might be worth doing, especially in high gravity worts, but it's not a necessity.

The diamonium phosphate, wine type nutrients are pointless in beer though because there's no zinc in them.

Since i started using wyeast all my beers finish where they should. I will continue using it as its cheap enough. As you say no point using wine nutrient.

 

[svenito]

I haven't used liquid yeast yet, but for dry yeast I just pitch a second packet if the wort is over 1.050. Haven't hydrated any yeast either and have always managed to hit FG (or a bit lower)

 

[Dutto]

And that is, does anyone regularly put yeast nutrient into their wort?
and if so why?

The answers for me are:

1. "Yes."

2. "Habit and to allay the fear of a stuck brew."

 

[Drunkula]

I've used it after a spell of dreaded 1020s but that was all on kits that were old. I added it to stuck ferments, sometimes it still didn't work and I aerated again and that did work. Jamil Swedishchef said the only times he's ever had stuck ferments is when there was a zinc problem as zinc is critical for yeast growth. Wilko nutrient has zinc in it.

During the 1020 spell I even grated some vitamin tablets with zinc into the wort. Not had the problem with all grain - yet.

 

[Dutto]

.......... I added it to stuck ferments, sometimes it still didn't work and I aerated again and that did work. ...........

That's amazing! I've been told by a scientist that fermentation is "anaerobic" and oxidation of the wort just won't work.

He even showed me a chart that proved everything. :whistle:

 

[Sadfield]

Never had a stuck fermentation. I do on occasions use yeast nutrient, usually on high gravity beers or when fermenting at lower temperatures.

 

[Sadfield]

That's amazing! I've been told by a scientist that fermentation is "anaerobic" and oxidation of the wort just won't work.

He even showed me a chart that proved everything. :whistle:

A scientist may also be able to tell you oxidation and aeration are two different things.

The scientist may also have actually informed you that ethanol production is the result of anaerobic respiration. Something which is proven scientific fact. They teach kids this stuff. http://www.bbc.co.uk/schools/gcsebi..._microscope/useful_microorganisms/revision/2/

A scientist may interpret the spurious anecdotal evidence of aeration as having acted as a mechanism for getting flocculated yeast back into suspension, aiding fermentation. A scientist may also know that oxidation late in fermentation isn't a good thing for flavour stability.


"Inspiration is the impact of a fact on a well-prepared mind" Louis Pasteur

 

[Dutto]

This is getting really confusing.

According to Wikipedia:

Anaerobic means "living in the absence of air", as opposed to aerobic which means "living in the presence of air."

And according to this article ...

http://howtobrew.com/book/section-1/yeast/yeast-nutritional-needs/aeration-is-good-oxidation-is-bad

You want to cool the wort to fermentation temperature and then aerate the wort to provide the oxygen that the yeast need to grow and reproduce.

Then you want to protect the beer from oxygen once the fermentation is complete to prevent oxidation and staling."


A "stuck brew" means that the fermentation isn't complete so, until the fermentation process is completed, what is in the FV is "wort" and not beer.

 

[Sadfield]

From the book BREW CHEM 101 by Lee W. Janson, Ph.D.

Stages of Yeast Activity in Fermentation

After the yeast are added to, or pitched, into the cooled wort, they go through three separate processes leading up to, and including, fermentation.

THE INITIAL PREPARATION PERIOD is essentially a “waking up” and “checking out” period for yeast that have often been dried, processed, packaged, and/or shipped across the country. The waking up phase involves cell-wall preparation, nitrogen uptake, sugar uptake, and oxygen uptake. In other words, the yeast utilize the wort to get themselves in shape for fermentation. A wort that is missing required sugars, proteins, lipids, or ions at this stage will slow or halt the preparation of the yeast.
Even if the yeast are healthy and already actively growing, they will still have to consider, or check out, the new growth environment before committing to it. A yeast colony will not want to put its valuable biological resources into a potentially poor home, so a quick check of food and space is as essential to a yeast cell as it is to any living organism.
The length of time required for all of this preparation is directly related to how healthy the yeast are. Sick or weak yeast won’t be prepared as fast as healthy yeast. Dried yeast that come straight out of a packet will take longer to recover than a liquid culture of yeast already growing in a food-filled media. However, even actively growing yeast will still go through a “pitching shock” lag as they check out and get used to their new home.

AEROBIC (WITH OXYGEN) RESPIRATION is the second stage of yeast activity. Yeast cells can get fifteen times more energy from a sugar molecule if they use oxygen. Therefore, while oxygen is available in the wort, yeast will feed using aerobic respiration. The energy produced will help yeast grow and multiply. This is why you want to aerate your wort at the beginning—to get lots of healthy yeast cells before anaerobic fermentation starts. Aerobic respiration produces six molecules of carbon dioxide (CO2) per sugar molecule metabolized, so you’ll start to see bubbles form, despite the fact that alcohol is not being produced. Assuming you have healthy yeast, the time spent in the aerobic respiration phase is directly related to how much dissolved oxygen is in the wort.

ANAEROBIC (WITHOUT OXYGEN) FERMENTATION is the much awaited final stage of yeast activity. During this time, significant yeast growth and cell division still occur, increasing the number of yeast cells. Since all the oxygen is gone, the yeast cells turn to anaerobic respiration, which leads to ethanol production. One molecule of CO2 is produced for each ethanol molecule produced.

Aeration when the yeast has reached the third stage is pointless as yeast will still grow under anaerobic conditions. Further more it is a bad idea as it will oxygenate the part fermented wort leading to oxidation issues in the fermented beer.

Also from BREW CHEM 101 by Lee W. Janson, Ph.D.

OXIDATION

Off Flavor
Winey, wet cardboard, papery, rotten or old vegetables, pineapple, sherry, baby diapers, or nutty. Increasing sourness, harshness, and bitterness.

Source

Oxidation can take place among a number of the components of beer, especially during aging and storage, to give a variety of what is described as stale and old flavors. Oxidation involves the interaction of oxygen and the molecules in beer, a process increased by high temperatures. Oxygen can get into the wort and beer in a variety of ways, but the most common include continued aeration of the fermenting wort after the yeast pitching and unnecessary aeration or excessive head space in kegs or bottles.

Some info on stuck fermention from beerandwinejournal.com.

If your fermentation is stuck, you can sometimes remedy the situation. Depending on the problem, this fix may be fairly simple or more involved. In every case, your first step should be to try to rouse the yeast.

Yeast can flocculate (drop out of solution) suddenly for a variety of reasons, including low temperatures, lack of nutrients or a stressful fermentation.

Hope this helps with your confusion Dutto.:thumb: