Dry Yeast v. Liquid Yeast


I’ve been messing around with brewing mead and wine recently in addition to my beer brewing activities. It’s a veritable 24 hour brewing circus around my house with any free minute filled with fermentation of some kind. At the moment my living room smells like a fermentation room at a winery. Stephanie loves that kind of thing.

Anyway, wine and mead makers tend to use dry yeast as opposed to beer makers who tend towards liquid yeast. Older style beer kits that come in a can still include a packet of dry yeast (or so I’ve been told, I’ve never actually made one), but most contemporary recipes call for liquid yeast from Wyeast or White Labs. From what I can tell, most serious brewers are using liquid yeast and making starters to pitch into their wort in order to get a proper yeast cell count for a clean fermentation. There are a few yeast pitching rate calculators out there from Wyeast and from Jamil and some well read articles that serve as the guidelines for making and using starters.

Standard brewing practice also involves either shaking the crap out of the carboy to aerate the wort or using an oxygen tank and diffusion stone to dissolve pure oxygen into the wort. Yeast use oxygen to make lipids/sterols for their cell membranes. Healthy cell walls allow for better yeast growth and propagation, better uptake of nutrients, and better alcohol tolerance. Healthier yeast means cleaner fermentations and fewer off flavors in the final beer. There has been a interesting series of posts from Mike Flaminio on wort oxygenation on the Homebrew Beer Blog recently as well. The aim there being consistent, proper wort oxygenation as opposed to the blind process most of us follow that apparently leads to inconsistent over oxygenation. There has also been a long thread on the Brew Board about using very small amounts of olive oil in the wort instead of oxygenating it. Yeast apparently can uses the olive oil to synthesize the lipids/sterols they needs for their cell walls.

Wine kits just ask the wine maker to sprinkle a packet of dry yeast on top of the must to start fermentation. Some wine makers rehydrate their yeast prior to pitching, usually in Go-Ferm. There seems to be some debate in the wine making community about which practice is preferable, with a larger number of people taking the wine kit makers advice (from my limited reading and experience). According to Tim Vandergrift at WinExpert, the leading wine kit manufacturer:

“The real scoop on why kit companies don’t ask you to rehydrate: It doesn’t make any difference.

In the 6 US gallon (23 litre) volume, the 5-gram packet of yeast provided will ensure a quick and thorough fermentation with a quick sprinkling and nothing else.

It is technically true that re-hydrating gives higher viable cell counts–but only if you do it with perfect precision and accuracy. While there are a couple of pitfalls, the commonest one is temperature shear.

Since you have to rehydrate at 100F, in ten times the weight of the yeast in pure water, the yeast slurry will be fairly warm. If you pitch this re-hydrated mass into a must of 64F, the shock of the wildly disparate temperatures will kill a lot of those previously viable yeast.

In tens of thousands of trials, we’ve never seen anything approaching sub-optimal times for culture strength and subsequent fermentation.”

In either case, there are no starters and no oxygenation occurring, though wine makers do sometimes stir their must and/or leave the fermentation chamber relatively open compared to brewers in order to get more oxygen dissolved. These are some pretty divergent practices, so I’d like to know how or why this is the case.

I found a response to questions about starters and oxygenations from Dr. Clayton Cone at Danstar/Lalleland/Lalvin, a leading manufacturer of dry yeast, that I found pretty interesting. Basically he says that dry yeast come packed with the amount of lipids needed to triple the yeast cell count. After those lipids have been used up, additional oxygenation is required for healthy cell growth. For brewing a 5 gallon beer between 3% and 5% alcohol, no additional yeast or oxygen are needed apart from what is available in a single 11g packet. For higher alcohol content beer, you either need to pitch additional yeast or oxygenate to allow for yeast growth. I’m not sure what Danstar considers a proper pitching rate, so that is something I will have to investigate. I do know that Jamil recommends pitching about 10g of yeast on average for an average gravity 5 gallon batch in Brewing Classic Styles. [Edited per Jamil's comment. Thanks Jamil. And as Jamil notes, batch size, OG, and yeast type are all variable inputs in the proper pitching rate - use his calculator to get precise amounts- I do.]

As a brewer, I’d prefer a higher pitching rate for higher alcohol beers so that propagation was mostly complete at pitching instead of trying to grow the yeast in the wort. That way the yeast can spend their time fermenting while in my wort instead of growing.

Dr. Cone mentions that Danstar grows their yeast along a different metabolic pathway than the one used by brewers that uses basically no sugar. Yeast propagated this way create very little alcohol. I assume this is done because it allows for more efficient healthy yeast production. When growing yeast in a starter, “no matter how much air you feed the fermentation, alcohol + CO2 are the main by-products. Your starter culture will have a much higher level of sugar [than the culture used by Danstar]. You will produce some cell mass but mostly alcohol and CO2 no matter how much air you add by stirrer or bubbles.” So starters increase cell counts but not in a way that is as effective as the propagation method used by Danstar. I guess that this also means that yeast grown in a starter, even under ideal conditions for a starter, is of a smaller amount and of potentially of lower quality due to the presence of alcohol and other less than ideal conditions.

So I guess my question is whether making a starter is an effective way to increase yeast cell counts prior to pitching or if instead it’s just a way to get yeast into active fermentation prior to pitching. Perhaps they generally make alcohol and CO2 and that starters are not the ideal environment for propagation even with the proper amount of oxygen. Buying 2 vials of White Labs yeast or 2 Wyeast Smack Packs is prohibitively expensive, especially given the increased cost of malt and hops. So I understand why people look for ways to grow their own yeast. But dry yeast is relatively inexpensive and prepackaged with the lipids necessary for healthy propagation and fermentation. Pitching a packet of dry yeast that cost less than $2.00 is definitely cheaper than pitching a starter made from DME, yeast nutrient, and a $6+ liquid yeast product – and that doesn’t count in the cost of the equipment needed to make starters (flasks, stir plates, etc.) or the time involved. If the metabolic pathways used by yeast from a starter for propagation produce lower quality yeast than the yeast from dry packets, that makes using dry yeast even more appealing. And if re-hydrating dry yeast generally makes no difference, all the better.

Of course liquid yeast manufacturers make a far wider variety of yeasts than are available as dry yeasts, so sometimes your options are limited.

I’ve never used a dry brewer’s yeast, so this is all just speculation at this point. I’m planning on trying out some dry yeast and comparing the results to equivalent liquid yeast from starters. I ordered 12 packets of dry yeast, 2 each of 6 different varieties, from Williams Brewing mostly because they are having a sale on dry yeast – 25 cents off each packet of dry yeast when you buy 12 or more. We’ll see what happens, but I am hopeful that I’ll get good results. If dry yeast is a reasonable or better alternative to liquid yeast and starters, maybe more people will start using dry yeast and more varieties will be made available. Or it might suck and I’ll go back to liquid yeast starters.

Tagged , ,

10 thoughts on “Dry Yeast v. Liquid Yeast

  1. I think there might be a typo here. I don’t recommend pitching two 11 gram packages of dry yeast, unless you’re making a very large batch of beer or one of exceptional strength. The amount of dry yeast needed is going to vary with the starting gravity, wort volume, and if making an ale or lager beer. You can find my pitching recommendations by using the pitching rate calculator at my website, http://www.mrmalty.com.

  2. Lee Koehler says:

    That will teach me to quote something from memory instead of looking it up to verify it first. I hope I am just remembering that from the recipes I have brewed, but it’s probably faulty memory. Again, thanks for the pitching rate calculator and every thing else too Jamil.

  3. Lee Koehler says:

    Jamil is of course correct. I edited my blog for clarity and noted the correction. The recipes I was recalling used 2 5g packets of dry yeast, not 2 11g packets.

  4. Interesting article. I’m about to work with some dry yeast batches and I’ve been pondering the whole hydrate or not and oxygenate vs not thing.

    If Jamil is still watching, his calculator figures 1.7 (20g) of dry yeast for a 1.048 lager. Here, you’re basically pitching two packs, so curious if we’re only talking ales or just go with one pack for a lager too?

  5. Lee Koehler says:

    I was just talking ales, which I should have made clear. I’ve had this problem with lagers – my very young son likes to pull the thermometer probe for the controller out of my fermenter – which makes maintaining lager temperatures difficult. My plan is to use the recommended pitching rates from Jamil’s calculator when using/testing dry yeast. I’m also thinking about comparing some oxygenated v non-oxygenated batches with dry yeast. The biggest holdup at the moment is getting together enough small fermenters that I can do them all at once with the same batch of wort.

  6. Dave Lubertozzi says:

    I wrote a similar essay (below) three years ago for the BAM newsletter, it stirred up exactly zero discussion. At the meeting last nite dry yeast was discussed, with the caveat that “it’s getting better…but” and there was still the general perception that it’s somehow not as good – in particular, the idea was bounced around that dry yeasts are not as clean as liquid. Without any hard data on that, I’d have to relegate that idea to the realm of superstition.

    The upshot: three years after writing this, I’ve had nothing but great results, and become a total dry yeast convert. I’ll still use liquids when I want a specific strain that’s not available dry, but that’s the only reason to IMO.

    Dry brewing yeast: as good as liquid?

    Or maybe even better…?

    When I first started brewing, I was advised to throw the packet of dry yeast that came with the can of malt extract in the garbage, and get a Wyeast smack-pack instead, because the results were always superior. I’ve used it ever since, or the White Labs. Between them, they have almost a hundred strains to choose from, and their literature is full of glowing sensory descriptors such as “malty, minerally, spicy” etc. and also gives attenuation, flocculation and other tips. What more could you want?

    Well, the last time I brewed, I made a Vienna lager with some old yeast I’d saved, and since I was unsure it was still alive, I bought a packet of dry yeast as insurance. Sure enough, mine was dead, so I put the dry yeast in and it kicked right up in a few hours. I put it in the fridge that night, and it’s bubbling along happily at 35º. The same day we did another batch for my friend, and put in a Wyeast “Activator” pack, which I hadn’t activated – I didn’t realize it was still a smack-pack, and in fact they advertise that it has just as many cells as the White Labs tube, so you can just pitch it in. I mixed and aerated well, but after 48hrs, the only activity was a wee bit on the floating (unbroken) inner nutrient pouch, which I guess had a little yeast stuck to it, and since it was on top it got enough O2 to get going. That night I sprinkled a packet of SafBrew S-33 on top, and within a few hours it was going strong.

    This got me thinking, why am I using liquid yeast? Let’s compare:

    Yeast Cost Shelf life preparation activity
    Liquid $5 – $6 4 – 6 months* 24 – 72 hrs† variable
    Dry $1.50 – $2 2 years** 30 min‡ high

    * if you’re lucky; the liquid ale yeast was made in April
    ** the SafLager S-23 I used was actually right on the expiration date, seemed good as new
    † You may have to make a starter; they guarantee it’ll swell in 6 days, which seems pretty sad really
    ‡ if you rehydrate it; just sprinkling it on top seems to work just as well

    OK, so why are liquids better? Because they’re “fresh”? What good is that if they don’t start up quickly?
    My experience in ten years as a baker is that nobody uses fresh yeast any more, because dry is much better in terms of shelf life and activity; the best brands were SAF (Fermentis) and Fermipan (Lallemand). Similarly, winemakers have used dry yeast with no complaints forever, only recently have liquids made a foray into the wine world. I just started a mead with dry ale yeast too. I’m curious to see how it goes, since meads are notorious for being slow and often stuck fermentations – so far, so good.

    My recent experience in microbiology leads me to believe that liquid yeasts took over because a small lab can easily go out and culture yeast strains from various sources, and prep and package them quickly. The large array of available strains puts the choices in dry yeast to shame. To make dry yeast profitable, it needs to be done in a fairly large scale (in fact, Fermentis offers to culture your preferred strain and dry and package it for you, but only with a minimum order of 1,500 kg or more of dry yeast!). That doesn’t make it inherently inferior, just different. The small liquid labs were ideally poised to take advantage of the home- and craft-brewing market, and they make a fine product, but right now, I’m thinking of becoming a dry yeast fan. I like the idea of keeping a dozen or so packets on hand, so I can brew at a moment’s notice and not worry “is my yeast alive?” Even if the packets with those old malt cans weren’t any good, that doesn’t mean dry yeast is all bad. There are not as many choices as in liquid, but there are at least a dozen to pick from, so you should be able to vary the yeast to suit the beer style reasonably well. Of course, for us, taste is the final arbiter. I haven’t brewed with dry yeast until now, so I’m eager to taste the results, and will share the tasting notes (if not the beer ;-) with all of you soon.

    Here are some links to dry yeast info:
    http://www.crosby-baker.com/DCL.htm
    http://www.fermentis.com/FO/EN/00-Home/10-10_home.asp
    http://consumer.lallemand.com/danstar-lalvin/danstar.html

    I’d be interested to hear what others have to say about this, maybe we can get a discussion forum on our website?

    - Dave Lubertozzi 7/20/05

  7. Dave Lubertozzi says:

    oops – forgot to format the table for html, here it is:

    table

    Yeast
    Cost
    Shelf life
    preparation
    activity

    Liquid
    $5 – $6
    4 – 6 months*
    24 – 72 hrs†
    variable

    Dry
    $1.50 – $2
    2 years**
    30 min‡
    high

  8. Dave Lubertozzi says:

    Lee Koehler wrote:
    I am very excited to hear someone is interested in more than a passing fashion in the topic.

    I’m sure the dry yeast manufacturers are pretty seriously interested in increasing their market share, although I wonder how much yeast homebrew and even craft brewers actually buy (I guess that would depend on what your barrel/year cutoff is between micro, craft and macro – I assume all the larger breweries re-culture their own yeast, but maybe not). Regardless, besides great tasting beer and a fun hobby, I’m motivated to brew partly by frugality – i.e. I’m cheap! So with increasing ingredient costs it sure makes sense to do what you can to hold down your batch price; if we can do that without sacrificing quality, and in fact have increased convenience and consistency, I’m all for that. How could anyone be against that? I do want my homebrew store to do well, so I guess the more dollar value of stuff they sell the better off they are, I know their margins are slim now – but I’m going to recommend to my local guys that they just stock one liquid (they now have a big selection of both Wyeast and White Labs) and get all the SAF and Lallemand yeasts they can. It’d be a shame if we (they) lost homebrewers (customers) because they decided it wasn’t worth paying $15 for grain, $6 for yeast, and $3.50 for hops + incidentals = $25/5 gal batch + your labor…heck I can almost buy good beer for $10/gal at the store ;-)

  9. Bruboy555 says:

    I am very glad I happend along and found this thread. My brother always uses liquid yeasts, and had been urging me to do so as well. I resisted mostly because of the price, but was swayed by his assertions that the liquid yeast made a “cleaner” beer. I have used a few liquid yeasts, mostly White Labs for Octoberfests and some Wyeast for Belgian Abbey, but was not totally convinced I could tell the difference between them and my good quality dry yeasts. I will say this, the liquid yeasts I have used have uniformly been very good, while some of the low buck dry yeasts have had some poor performance in terms of attenuation at least. I think the dry yeasts like Danstar Nottingham work well for beers up to about 6% ABV, while the Wyeasts liquid strains seem to be a bit more tolerant of high alcohol levels. For most mid range beers, I think dry yeasts are fine. I think going forward I will save the liquid yeasts for my high gravity brews.

    Thanks for spending some time on this and keep up the good work.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Follow

Get every new post delivered to your Inbox.

%d bloggers like this: