Jump to content
Sign in to follow this  
Beerlust

"Proofing" Dry Yeast

Recommended Posts

I really don't understand the desire for a fast start, especially don't understand pitching in the high end of the temperature range to encourage the yeast to multiply faster. There is an alternate argument, as there always is, that suggests pitching at the lower end for example 16 degrees is a superior option.

 

Personally I aim to pitch at my desired fermenting temperature, I don't mind if my BRY-97 takes between 24 and 36 hours to fire up as long as it does. It is however the only yeast that I regularly rehydrate in cooled boiled water straight from the tap.

 

Cheers & Beers

Scottie

Valley Brew

Share this post


Link to post
Share on other sites

The fast start thing is probably a bit of peace of mind knowing that the yeast has taken hold as the dominant bug over the rest. However, I don't stress if it takes 24-36 hours either, as my pilsner batches always do this most likely due to the lower temperature, but I've yet to pitch one with cold yeast yet.

 

I prefer to pitch my yeast into wort that is already at fermenting temp or very close to it; I do think the warm pitching is an inferior method. Having said that, I build yeast up in starters, so there is already plenty of it being pitched and it doesn't have to multiply as many times. As has been documented in other threads, I also pitch it cold straight from the fridge and since doing this have been getting the shortest lag times I've ever had. The last few ales I've done have been up and going with a noticeable sized krausen in somewhere between 12-18 hours.

 

Of course, the cold pitching thing can't really be done when simply re-hydrating as it would take too long to chill it down; it really is something that can only be done with either yeast starters or jars of saved slurry.

 

Cheers

 

Kelsey

Share this post


Link to post
Share on other sites
I really don't understand the desire for a fast start' date=' especially don't understand pitching in the high end of the temperature range to encourage the yeast to multiply faster. There is an alternate argument, as there always is, that suggests pitching at the lower end for example 16 degrees is a superior option.

 

Personally I aim to pitch at my desired fermenting temperature, I don't mind if my BRY-97 takes between 24 and 36 hours to fire up as long as it does. It is however the only yeast that I regularly rehydrate in cooled boiled water straight from the tap.

 

Cheers & Beers

Scottie

[i']Valley Brew[/i]

 

Hi Scottie. Just to clarify, when you say you aim to pitch at your desired fermenting temp, are you talking about dry pitching, or rehydrating dry yeast at fermentation temps? I assume you mean the later. If so, are you just referring to ale yeast? What about lager yeast? I'd think that for dry lager yeast you need to rehydrate (or dry pitch) at least above 15C.... Cheers Scottie. -Christina.

Share this post


Link to post
Share on other sites
All good Ben. smile

 

As a bit of a "dig" though on my part' date=' & for those interested in your thoughts (as I always am), can you please elaborate a little further on the "Interesting thread with a fair bit of ill informed bollocks" comment to clarify what you are perhaps taking exception to?

 

Cheers,

 

Lusty.[/quote']

 

Why would that be necessary

Share this post


Link to post
Share on other sites
I really don't understand the desire for a fast start' date=' especially don't understand pitching in the high end of the temperature range to encourage the yeast to multiply faster. There is an alternate argument, as there always is, that suggests pitching at the lower end for example 16 degrees is a superior option.

 

Personally I aim to pitch at my desired fermenting temperature, I don't mind if my BRY-97 takes between 24 and 36 hours to fire up as long as it does. It is however the only yeast that I regularly rehydrate in cooled boiled water straight from the tap.

 

Cheers & Beers

Scottie

[i']Valley Brew[/i]

 

Hi Scottie. Just to clarify, when you say you aim to pitch at your desired fermenting temp, are you talking about dry pitching, or rehydrating dry yeast at fermentation temps? I assume you mean the later. If so, are you just referring to ale yeast? What about lager yeast? I'd think that for dry lager yeast you need to rehydrate (or dry pitch) at least above 15C.... Cheers Scottie. -Christina.

 

Hi Christina

 

I pitch at fermenting temperature, however 97% of my brews are Ales. I pitch mostly US05, Nottingham and Windsor dry and mostly rehydrate BRY-97. The article I read suggested that maybe pitching under the ferment temperature and then increasing was better as pitching high to encourage a fast start may stress the yeast and led to undesirable flavours in the brew. I have no real issue either way, I chill my boiled wort with a plate chiller so pending the ambient conditions I can vary between 20 and 16 degrees and I am pitching into every one of those worts as soon as the kettle is drained.

 

Cheers & Beers

Scottie

Valley Brew

 

Share this post


Link to post
Share on other sites
much like bakers do.

 

I worked as a baker and pizza cook for years and never added any sugar to yeast to get it going. Bakers yeast will take off in 5 minutes regardless. There is no need for that.

 

Makes a quicker start' date=' than simply adding rehydrated yeast

[/quote']

 

I'll put money on it making no difference at all

 

Dryed yeast pitches fine eather sprinkled on top or rehydrated or proofed' date='

[/quote']

 

Optimal cell count comes from rehydrating in water, as per the manufacturers... it is a function of the drying process

 

Do not proof in water there is no food for the yeast' date=' it will activate and die

[/quote']

 

There is plenty of food stored within the yeasts own cell. That is why the yeast goes creamy and often foams when placed in water.

 

 

Good luck with the experiment but I do not see how introducing another step will make anything faster or better.

Surely a rehydrated yeast pitched into the FV will take off just as fast as one fed malt 30 minutes prior?

Share this post


Link to post
Share on other sites
Interesting thread with a fair bit of ill informed bollocks.

 

Dry yeast should be REHYDRATED in WATER.

 

 

 

Absolutely.

If you can't rehydrate or make a starter, dry pitching is the only other method of introducing your yeast to the wort without causing harm - assuming you're within the correct temperature range for the yeast.

 

There is absolutely no valid reason to proof your yeast, as you're likely to do it more harm than good, which will have the same impact on the brew you pitch it into.

Share this post


Link to post
Share on other sites

Except dry pitching does cause harm. Or at least, it has the potential to; I've yet to see any empirical evidence that backs up the 50% death rate of cells by dry pitching claims. The theory is that the osmotic pressure from the wort bursts the cell walls and kills them. However, I would rather not take that chance, especially when the solution is as easy as boiling and cooling some water and throwing the yeast in it for 20 minutes.

 

I also see no huge advantage to this "proofing" technique. It seems like an unnecessary step to me.

Share this post


Link to post
Share on other sites
Except dry pitching does cause harm. Or at least' date=' it has the potential to; I've yet to see any empirical evidence that backs up the 50% death rate of cells by dry pitching claims. The theory is that the osmotic pressure from the wort bursts the cell walls and kills them. However, I would rather not take that chance, especially when the solution is as easy as boiling and cooling some water and throwing the yeast in it for 20 minutes.

 

I also see no huge advantage to this "proofing" technique. It seems like an unnecessary step to me.[/quote']

 

Agreed, but with a lack of empirical evidence on the 50% death rate of yeast cells from dry pitching, I'd be very interested in any research that backs this up.

Certainly I've noticed that dry pitching results in a brew taking longer to start fermentation, & it generally takes a little longer, but I have to wonder if that may be more about the yeast taking longer to acclimate than about cell death.

Obviously no matter how much or how little yeast you pitch, provided it's a viable yeast, you'll find the cells will divide, & you'll have many more cells at the end of a brew than were originally pitched.

 

I don't understand how dry pitching can cause more cell death than re-hydration, seeing as you just pitch into water to re-hydrate, which forces the cells to consume the nutrients they were dehydrated with, whereas dry pitching allows the cells to consume the wort once they have adjusted to the change of conditions.

 

As you say there is a theory of osmotic pressure bursting the cell walls, but if that's the case why does this not happen in starters or re-hydration?

Or is cellular death inevitable, & it is offset by these processes?

 

Seeing as beer was made for hundreds possibly thousands of years before yeast was even discovered, I'd be very interested in exactly how much is really known about how yeast behaves, v.s. theories of what is thought to be the case.

There's a world of difference between perception, theories, observation, & repeatable reputable research.

 

All that said, with lack of empirical evidence, clearly the best path is to follow the advice of those who are more experienced, as well as not repeating processes that you've found ineffective.

Share this post


Link to post
Share on other sites

This is going around in circles,

 

I don't dry pitch any more but the funny thing is!

 

I think proofing is dead with the dinasours now... just like this thread

 

Personally it makes sense for me to rehydrate the yeast for safety sake!

Share this post


Link to post
Share on other sites

I would guess the dry pitching takes longer because if it does result in some cell death, then they will take longer to multiply to the required amount to ferment the brew. Obviously the yeast will always multiply when pitched into a wort, but if the initial amount of cells is too small, the yeast will stress, throw shitty flavours or not even kick in to begin with.

 

Wort is obviously a different composition to straight water. It is of a higher density for one thing, with all the sugars in it. Plus the hops, proteins and whatever else. It makes sense to me that this could cause osmotic pressure, resulting in the bursting of cell walls. There is always going to be osmotic pressure, but the point of re-hydrating dry yeast in water first is to allow the yeast to build up a sort of 'barrier' if you will, so that when it is pitched into wort, this pressure doesn't burst the walls. Or at least that's how I understand it. Of course, if you leave it too long to pitch, the yeast consumes all the trehalose stores, becomes vulnerable again and the process is futile.

 

It is NOT recommended to pitch dry yeast directly into a starter due to the same reasons. If you are going to make a starter with dry yeast it should be re-hydrated in water first.

 

I would say there is a fair bit known about how yeast behaves, the problem for us is being able to easily access this information. Maybe there is evidence out there, but where do you go to find it, you know?

 

 

 

 

Share this post


Link to post
Share on other sites
I don't understand how dry pitching can cause more cell death than re-hydration' date=' seeing as you just pitch into water to re-hydrate, which forces the cells to consume the nutrients they were dehydrated with, whereas dry pitching allows the cells to consume the wort once they have adjusted to the change of conditions.

 

As you say there is a theory of osmotic pressure bursting the cell walls, but if that's the case why does this not happen in starters or re-hydration?

Or is cellular death inevitable, & it is offset by these processes?[/quote']

 

 

Hi Beeblebrox. Seeing as how Kelsey hasn't answered, I thought I would try. I will start with your questions first: in the case of rehydration, the osmotic pressure of water is less than that of wort, so that is why most cells survive hyration in water. It does not happen so much in starters because starters are made with liquid yeast, slurry, or hydrated dry yeast. The cell walls of such yeast can regulate what comes into them, unlike dehydrated/dry yeast.

 

To your first point, I am not 100% sure, and stand to be corrected, but I would think that yeast sprinkled into wort still consume the nutrients they were packaged with (trehalose) before they consume nutrients in the wort (maltose). It stands to reason that the yeast manufacturers would recommend the time frame for pitching to coincide with the point at which the trehalose is consumed and the yeast need something else to eat.

 

As a side note, it is my understanding that if you save some slurry in the fridge overnight that the yeast respond to the cold by making trehalose, which sort of mimics the dehydration process. Makes me wonder if storing it in the fridge overnight is better than making a new batch on the same day as the slurry is harvested.

 

Cheers. -Christina.

Share this post


Link to post
Share on other sites

Thanks Otto & Christina, that clears it up a bit for me.

Clearly as brewing yeast is a commercial product, any really specific research, other than that which is deemed fit for the masses is held in confidence.

 

I hadn't even thought of re-hydrating pack yeast before making a starter, but it makes sense.

That said, my recent experience has shown that even making a basic starter without re-hydrating first still gives better results than dry pitching.

 

I guess we're all looking for the same thing though; how to obtain the optimal performance from your brew by boosting yeast cell counts, or at least reducing cell loss prior to pitching.

With that in mind, assuming you re-hydrate at the correct temperature, & introduce it to the wort or starter as soon as practicable, - earlier than 30 mins - or pitch a starter, you're bound to get quicker & faster results than dry pitching.

 

As for proofing; I can see that some may still choose to do it, but it's not best practice, & other methods are likely to yield better results, so really no point in doing it, other than out of curiosity.

 

For me, the take home message is continue to experiment with starters, & if I can't do that for some batches, at least re-hydrate prior to pitching, to reduce cell count loss, & reduce lag time.

Share this post


Link to post
Share on other sites

They also suggest not to re-hydrate yeast in distilled or RO water as it has a higher osmotic pressure; the minerals in tap water actually reduce the osmotic pressure.

Share this post


Link to post
Share on other sites

Hi guys.

 

Well today I've put this "Proofing" yeast practice to the test, & not just any test from my end.

 

I've used it on some BRY-97!! w00t

 

Given I've had 3 from 3 failures with this yeast, & those that have success with it claim long lag times, it seemed the obvious choice.

 

I followed the general consensus on re-hydration time (15mins), then added the re-hydrated yeast (200mls) to the same temp heaped teaspoon of dry malt extract dissolved in boiled water (200mls) & then cooled mixture. I allowed that to sit for the 30min time period also seen as advisable in this thread.

 

This was then pitched into a well aerated brew wort consisting of the following...

 

Coopers AUS Pale Ale kit 1.7kg

Light Dry Malt Extract 1kg

Table sugar 100gms

Cascade & Chinook 15gms each (flameout steep 30mins)

Cascade 10gms/Chinook 15gms dry hopped

Brewed to 21 litres

Ferment @ 18°C

 

Given my previous issues with this yeast, I didn't wish to waste it on an expensive, time consuming brew.

 

From the experiment side of things, all I'm interested in is if the lag time is improved, & improved by significantly.

 

Come to think of it, given my strike rate with BRY-97, I'll just be happy if the brew ferments! whistling

 

I'll update on how the early fermentation period goes.

 

Cheers,

 

Lusty.

Share this post


Link to post
Share on other sites
This process is pretty much the exact same thing that occurs when using Wyeast's liquid yeast smack packs. The nutrient contained in the inner sachet is burst releasing it into solution with the liquid yeast awakening them & placing them in an active state just prior to pitching. Having yeast in an active state prior to pitching into your main brew wort is generally accepted to reduce lag time' date=' & minimize the risk of outside infection(s).[/quote']

 

Hi Lusty. Thanks for the update.

 

To get back to the Wyeast liquid yeast smack pack, their instructions state, "Allow the package to incubate and swell for 3 hours or more at 70-75°F (21-24°C)." I have never used Wyeast and don't know what the contents of the nutrient pouch look like. Can you see the colour? How big is it? Given the three hour time period, it seems logical to assume there must be some (weak or regular strength) wort in it in it, but I am pretty sure it must also contain other nutrients, such as Go-Ferm. Product info states it is a mix of micronutrients. "If these micronutrients were added directly to the must, competitive microor­ganisms would use a significant amount of them." So it is basically a mini-starter, isn't it? Anyway, given that the micronutrients in Go-Ferm would be benefiting competative organisms as well if just added to the main wort, it might be an argument for making a mini-starter with dry yeast (rehydrated first of course) and really following what Wyeast does, and not just proofing in weak wort, which is a shorter process.

 

Cheers! -Christina.

Share this post


Link to post
Share on other sites

You can't see it since the packs are foil or something. But going by the colour of the yeast when you tip it into the starter or batch, it probably is wort. From Wyeast themselves:

 

2. Is the yeast in the small inner packet or in the foil pouch itself?

 

The yeast is in the main foil pouch. The small inner packet contains the sterile nutrient and wort that feeds the yeast before it is added to your fermenter. First, the package and the nutrient packet are sterilized (autoclaved) then the yeast is added and the package is sealed.

Share this post


Link to post
Share on other sites

As a novice brewer, the advice I've seen and followed has been to boil some water, let it cool to the advised temperature, stir in a bit of dextrose, add the yeast, cover for 25 - 30 minutes, and then pitch into wort. Sometimes there has been visible evidence of yeast activity, sometimes nothing at all; there always has been satisfactory fermentation from the pitch.

The most consistent advice I've seen seems to be that letting yeast rehydrate for longer than 30 minutes compromises the number of viable yeast cells available to pitch into the wort, so I don't understand the utility of waiting to prove the yeast. Is it really advisable to wait until the yeast proves, rather than to assume that yeast is viable, which in turn carries the risk of having to re-pitch the following day?

Share this post


Link to post
Share on other sites

I have some pure (if indeed that is the correct term unsure) powdered nutrient that is advised to be added 15mins before the end of the boil at a dosage rate of approx. ½ a teaspoon essentially to spread over a 20+ litre wort.

 

Information I've read around the traps advises against using this nutrient in starters, so if following that advise it seems inappropriate to use in a volume of only 400mls as I have created in this case. Even if you threw caution to the wind & went against that advise, measuring a suitable dosage against what is recommended for 20+ litres would be difficult, & possibly detrimental to yeast growth & health.

 

I've been tempted to throw a pinch of it in, but at this early stage of my trialing, I have thought better of it. Baby steps first I reckon. wink

 

Cheers,

 

Lusty.

Share this post


Link to post
Share on other sites

I wouldn't use dextrose for it. I honestly think it's a crappy recommendation, I mean, the yeast is going to ferment a bunch of sugars present in wort, it makes far more sense to get it started in wort as well. I have seen it mentioned that by starting the yeast in simple sugar like dextrose, it gets used to that, goes for the simplest sugars first when pitched into wort, and often slacks off and doesn't completely attenuate the more complex ones as a result.

 

I know Coopers says to re-activate their bottle dregs with dextrose, but I do wonder whether this is the reason why it seems to take off at a rate of knots and then slow right down towards the end.

Share this post


Link to post
Share on other sites
I know Coopers says to re-activate their bottle dregs with dextrose' date=' but I do wonder whether this is the reason why it seems to take off at a rate of knots and then slow right down towards the end. [/quote']

Tell me a yeast that doesn't behave this way?

 

I have said this before, but no harm in saying it again here. I feel there is a clear difference in the necessity for the involvement of maltose in simply AWAKENING yeast to place them in an active state prior to pitching as opposed to needing maltose for the healthy GROWTH of yeast cells prior to pitching.

 

It does make me wonder whether the need to add my re-hydrated yeast to dry malt extract in a proofing strategy is even necessary at all. After all, I'm not trying to increase cell counts (as I already have enough cells), I'm just aiming to place them in an active state prior to pitching.

 

I distinctly remember reading (not in the exact wording) PB2 once mentioning it is beneficial if the wort contains a certain amount of simple sugars for yeast to act upon. If I have misquoted PB2 on this one, I'm hopeful he'll correct me, as well as weighing in on this, as I'd personally be interested in what he has to say on this topic.

 

The awakening yeast vs yeast health/growth debate is an interesting subject I reckon.

 

Cheers,

 

Lusty.

Share this post


Link to post
Share on other sites
I have some pure (if indeed that is the correct term unsure) powdered nutrient that is advised to be added 15mins before the end of the boil at a dosage rate of approx. ½ a teaspoon essentially to spread over a 20+ litre wort.

 

Information I've read around the traps advises against using this nutrient in starters.

 

What is the name of this "pure" nutrient? Does it contain DAP (diammonium phosphate), which I mentioned earlier? Judging by the dosing you mention, it does.

 

DAP is an inorganic nitrogen source; it is toxic to yeast in the early stages. Any nutrient or energizer which contains DAP should not be added to starters, or too the boil; addition should be delayed until the first signs of fermentation appear. If you can not find any information about the ingredients of your nutrient, it is best to assume it contains DAP. I am not aware of any generic version.

 

But Go-Ferm is a different animal. It is intended specifically to be added to rehydration water of dried yeast. It contains sterols, unsaturated fatty acids, vitamins, and minerals; it does not contain DAP. A lot of commercial wineries use it, and some breweries too. The dosage is 1.25gm/1 gm of yeast/17mL of water.

 

https://www.morebeer.com/products/goferm-protect.html

 

Cheers! -Christina.

 

PS Boiled yeast (yeast hulls) provide organic nitrogen, sterols, and B Vitamins. They can be added to the boil.

Share this post


Link to post
Share on other sites

I've seen large packets of 'Brewers yeast' for not that much money at a couple of supermarkets; would that be a safe nutrient for addition to the boil?

Share this post


Link to post
Share on other sites

Back basics

 

Buy proper yeast nutrient for brewing beer,

 

Not yeast ... unless you wanna waste your money,

 

Anyway if your using Dryed Malt extract you don't even need yeast nutrients its in the dry malt!

 

Personally I put some yeast nutrient desgned for the job in my yeast starters...

Share this post


Link to post
Share on other sites
I've seen large packets of 'Brewers yeast' for not that much money at a couple of supermarkets; would that be a safe nutrient for addition to the boil?

 

Yes, or you could use bread yeast if you have that in the house already. Doesn't matter if it is expired. When I have bread yeast that expires, I just keep it. Boiled yeast is particularly good for adding to stuck ferments. Proper yeast nutrient is not that expensive though, even Go-Ferm, if you can find a source. So far I have not found a Canadian vendor; I would really like to track one down. I would like some as I also make hard apple cider and ginger beer, which are low in nutrients compared to wort.

 

Cheers! -Christina.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×
×
  • Create New...