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Fast Ferment Testing

Posted by mchrispen on 5/23/2015 at 10:12:40 AM

Fast Ferment Tests (FFT), sometimes called Forced Ferment Tests, have lost some favor in homebrewing. FFT can be used to measure the maximum fermentability of wort giving you an idea of where your beer's FG will land, and more specific information about the yeast's attenuation.

With the availability of very fresh and viable yeast in both liquid and dry forms, FFT  has been largely replaced by the best practice of creating a starter. FFT’s still have a role in brewing, and many breweries continue to run these tests when getting a fresh pitch of yeast or brewing a new recipe. Most sources cite Prof. Dr. agr. Ludwig Narziss for documenting this test and proving its usefulness.

The Procedure

Gather a small portion of your beer’s wort after chilling and aeration. You can use your hydrometer sample plus a few additional ounces, or a separate sample collected in a clean and sanitary vessel. Note your OG. Reserve some of your starter (or prepare extra cells in your starter) and pitch the yeast into the FFT. Usually, you will be over-pitching the cell counts which is fine for this test. Place the vessel, covered with foil or with an airlock at room temperature and let it ferment out. Note the FG and determine the apparent attenuation. This is more or less the level of attenuation and FG you can expect with the larger batch of beer. Generally, the yeast will attenuate further than it will under a cooler ferment in the larger batch, but give you very specific behavior information to compare.

The Vessel

Any sanitary vessel will work. I use flasks, beer bottles or glass or PET juice bottles. Anything that can be cleaned and sanitized will work. I seldom use an airlock, as foil is simple and allows additional oxygen uptake during the lag phase. Flasks are particularly useful and I often will use my 2L flask for this process. This also allows me to use my stir plate to continually rouse the yeast, accelerating fermentation. If you cannot use a stir plate, like making starters, swirl the fermenting beer up a few times a day for the same effect.

The Pros and Cons

There are many benefits using this method, the primary being that you are using the specific wort for your beer, including all of the issues that affect attenuation. When I am using a new yeast strain, I am getting very specific feedback: attenuation, expected FG in my particular beer’s wort composition, flocculation level and confidence in a successful fermentation. While the FFT is conducted warm, one can also detect the ester and phenol production of that yeast strain. Of course, if you use a stir plate or shake too often, you will likely get a fairly oxidized result. Once fermentation is complete, you can cold crash the FFT and taste the clear beer. You can harvest the yeast cake from this test for another batch of beer as long as you were very careful with sanitation, or use it to krausen the big batch of beer to help clean up fermentation off flavors.

Keep a Yeast Strain log. Note the pertinent information from the test, including the wort composition, gravities, attenuation and any particular notes, like flocculation, ester and phenol character, mouth feel, etc. Make sure to note the dates on the yeast as well.

The downside is really the extra process, and tying up potentially useful flasks or vessels. There is a bit more cleaning and sanitizing, but no more so than building a starter.

  1. Brew your beer adding a small additional volume for your FFT. I like to use about 1-2 liters, but you need just enough for a hydro sample after fermenting.
  2. Gather your FFT beer after you have chilled and oxygenated your wort. Note the OG.
  3. Pitch your yeast, at the required cell count in the big batch, and over-pitch your FFT
  4. Hold the FFT at room temperatures, occasionally rousing the yeast during fermentation. Optionally, use a flat bottom vessel and a stir plate. Or allow this to ferment at fermentation temperatures with rousing to create a beer with similar fermentation characteristics to the big batch.
  5. Upon completed fermentation, measure the FG and calculate apparent attenuation. Note any fermentation characteristics in your log.
  6. Optionally - cold crash the FFT and decant some clear beer for sensory evaluation. Note your findings in the log.
  7. Optionally - harvest and store the yeast in a sanitary vessel. Flame the lip or wipe with ethanol before transferring to prevent contamination. Store the yeast under the beer it created.


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Edited after some good feedback on Reddit. Hopefully more clear!

posted by mchrispen on 5/26/2015 at 10:09:24 AM

I love this. I am a huge proponent of forced ferment tests, and do one on almost every single batch. I find that using a canning jar with the ring loose works well, and swishing the wort through my smack pack, vial, or starter flask before pouring it into the FFT vessel gets me the pitching rate I want (see below). My typical FFT sample size is 7-8 oz., which is enough for me to do two hydrometer tests.

My rule of thumb for pitching rate on FFTs is approximately 10x the recommended pitching rate for your beer.

The FFT can also be done on fermenting beer, and is useful when you didn't do an initial FFT to determine whether your fermentation is stuck or truly finished. Doing a late-stage FFT is interesting because you may not have the primary fermentation strain available, nor may you wish to pitch the same primary fermentation strain if you suspect a stuck fermentation. So it may be useful to pitch a different attenuative strain to see if you can get the beer to attenuate more -- such as the second strain you might wish to pitch to unstick the fermentation (e.g., Wyeast 3711, WLP 090, Chico, etc.)

If you do a late-stage FFT, you will definitely want to do it on a stir plate, and ideally at warm temps (70-80°F). I find that the top of a stand-up refrigerator is a good place that stays warm enough for this purpose.

posted by chino_brews on 5/26/2015 at 03:21:19 PM

Tags for this post: yeast, attenuation, forced ferment test, fast ferment test, starter, harvest yeast

Hop Propagation Methods

Posted by vinpaysdoc on 4/18/2015 at 07:56:10 PM

It's Spring and many brewers are talking about their hops. This is a short and sweet article on how to increase your hop yard or share with friends. Me? I'm hoping to have Cascade take over my English Ivy.....
Methods to start growing:
1. Hop Plants - Available from a few merchants, notably Great Lake Hops. Be sure you pick these up from someone selling hops to brewers. If you pick plants up at the Farmer's Market they may be ornamental or male plants. Full plants will be best planted in the Spring.
2. Crowns - Crowns are 4 mo to 1 year plants that have produced cones and entered dormancy. They are usually available in the Fall and have the advantage that they have already developed a root system and will further establish themselves over the Winter. Plant them in the Fall and look forward to the Spring.
3. Rhizomes - Rhizomes are part of the root system of the plant that are pruned in late winter. They are widely available from many online retailers for pre-order and ship in the Spring. These are, perhaps, a little less reliable than using crowns.
4. Bine Cuttings - At the end of the growing season, when the leaves begin to fall off, cut the bine at it's base up to about 4-6 feet. Bury the bine about 4 inches deep in soil to over-winter. I would suggest that you put them in a planter so that the bines don't get confused with...
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Tags for this post: Hops, Growing, Propagation

The 7 Hour Boil, Single Malt Barleywine

Posted by wildscientist on 4/14/2015 at 10:20:49 AM

My normal brew day goes something like this: 8am pick up RO water, mashing by 9am, draining first runnings by 10:15am, do one batch sparge, have a nice rolling boil a little after 11am, and start cooling down my wort by 12:30pm - 1pm at the latest. Fill up carboys with cooled wort, place them into the fermentation chamber and pitch yeast. Everything is cleaned up and back in its place, ready to go for next time by 2pm; a nice and tidy 5-hour brew day from water to wort to future beer.

My basic brewing setup.

So what drove me to have a boil longer than my normal brew day? Well, it started with an article called "Meeting 'Mr. Maillard' After a Nine Hour Boil". The article describes a very simple process to make a very complex thing. It talks of food science and history and making something that's unique to what brewing has become today. The article focuses on Gigantic Brewing's barleywine Massive. Massive is a simple beer that belies the tasting notes you'll find online, and that's what intrigued me to make a similar beer. Based on Gigantic's own recipe, Massive uses 100% Thomas Fawcett Halcyon malt with Magnum hops for bittering, Cascade and Willamette for aroma and flavor, and then it's dry-hopped with Mosaic. Even before I looked up the recipe (and before I finished the article) I knew I was adding this to my brewing queue.

Now that I had a...
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Tags for this post: 7 hour, boil, maillard, barleywine, color

5 Minute All-Grain IPA!

Posted by skunkfunk on 3/25/2015 at 06:20:18 PM

Partly because of our favorite exBEERimentalist I've found my brew days  getting shorter and shorter. I'm done with the mash as soon as I hit gravity, I don't worry about trub, and I've even quit chilling below 120F before throwing the beer in the fermentation chamber.
Well, this one needs to be even faster! My firstborn arrived 2 months ago and I was told that I didn't have time to brew. My wife also complained about the humidity of a stove top boil which rules out a small BIAB batch, too. Or does it?
This is a little experiment of mine. Keep in mind this isn't answering questions about what difference a boil makes, or whether your beer will be better with or without it. There is no control batch, only the final beer. My intent with this brew is to find out whether I can make a good beer with less boil time! Surely this will have intolerable DMS, you say? Let's find out. To reduce this possibility I'll avoid using any pilsner malt  and make it an ale, as DMS may or may not be somewhat  more volatile at ale fermentation temps than at lager temps. I'll likely rarely (if ever) use this technique going forward but why not see whether I can learn anything from it?
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Tags for this post: IPA, boil, homebrew, f minute

How to Toast Flaked Oats - a Video Tutorial

Posted by homebrewdad on 3/20/2015 at 12:49:17 AM

This coming weekend, I am taking another stab at brewing an oatmeal toffee stout. Of course, like any oatmeal stout, it will contain flaked oats.

Flaked oats, like other flaked grains (flaked barley and flaked wheat) add body, head formation, and head retention to a beer. However, flaked oats are special - they add a fantastic, silky creaminess to a beer that is tough to duplicate with any other method or ingredient. I personally get my flaked oats from the LHBS as they are inexpensive and I can do some "one stop shopping". Others prefer to pick up instant oatmeal from the grocery store, due to the fact that it's the same thing. I haven't priced the two side by side, and am not sure that it's worth an extra trip to the grocery store to potentially save a few cents on oats... but YMMV.

They don't add a ton of flavor by themselves, but if you toast your flaked oats, you can absolutely add another layer of flavor to your beer. I've heard the flavor referred to as biscuity, toasty, or nutty; for my money, it's a slighlty nutty, somewhat "oatmeal cookie" flavor that plays really well in a stout - though I could see it going well in a brown ale, as well.

The process is honestly quite simple; the video below will walk you through the entire proceedure. Recently, my pal Derek of Five Blades Brewing did an excellent post on toasting oats - it's worth the...
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Tags for this post: toasting, toast, flaked, oats, brewing

Brewing a Small Batch With the Big Boys - My Brewday at Harpoon

Posted by tracebusta on 3/17/2015 at 09:13:35 AM

I work for a restaurant group that has a small handful of restaurants, a cocktail bar, and a non-profit organization that educates elementary/high school kids on food. Every year we do a fundraiser in order to buy all the school supplies needed. This year Harpoon decided to make a beer specifically for us; and luckily for me, a sous chef and I got to help with the brewing.

The beer is a German lager. We didn't use their house yeast, instead they had been propagating up some German Helles yeast. We were aiming for a session beer, right around 4%. We wanted a very full body, and hit a mash temp of 160F. This was also a small batch, we ended up at 305 gallons; just a hair under the 10 barrel mark.

The mash/lauter tun

The boil kettle
The strike water had been heated to 182F starting the night before. By the time it got through all the piping...
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Tags for this post: homebrewing, homebrew, Harpoon, brewery, 10 barrels

Culturing Yeast from the Bottle/Can

Posted by Matt on 2/27/2015 at 08:23:53 AM

About six months after I started brewing, when I first realized how important yeast selection was in the final product, I went a bit nuts with yeast and I haven't really recovered. Most everything I do is a split-batch between yeasts, and I honestly find trying new yeasts exciting. Real world example, I recently ordered two new kinds of yeast and made a three-way-split-batch on a whim because someone brought it up. Evidence here. I'm a big believer that finding the right yeast is one of the keys to a great beer, and so when I encounter a great beer one of my first questions is "What yeast did you use?". 
Unfortunately, when I ask this question about a commercial beer, the answer isn't always out there, especially since most breweries filter out the yeast from their beer. Some breweries are incredibly private about the strain of yeast they use, many which may not have an available equivalent anyways. So when I come across an unfiltered bottle of great beer, I can't help but get excited and prepare to add a new kind of yeast to my collection. 
So, how do we go about culturing yeast from a bottle/can? 
Step One: Find an unfiltered beerObviously, you need to find a beer to culture the yeast from. There are quite a few breweries out there that don't filter their beer. Find one that you like and go with it!...
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Tags for this post: yeast, bottle, beer, can, culture, grow, cells

DIY Universal Heating Element

Posted by brianj on 2/25/2015 at 01:48:13 PM

Editor's note: You should always consult an electrician before building, installing, and using DIY electrical projects.

I brew electric but my setup is quite simple. I have 2 of these elements installed in my boil kettle (also doubles as my HLT). This is a good project if you want to start converting over to electric but do not want to get into elaborate panels. The only caveat is if you are using more than 1 of these, make sure you plug them into separate circuits. Otherwise, the current draw will be too great and you will pop a breaker. For my setup, I installed 2 dedicated 120v / 20A GFCI switched outlets in my brew area. You will find many electric setups use much stronger heating elements and have some type of system in place to dial back the current once you achieve a boil. The reason for this design is for a few reasons. There is a greater liklihood that you have 120v outlets available as opposed to 240v. You can regulate the current simply by turning elements on or off (as mentioned above, mine connect to individual switched outlets). If an element fails in the middle of your brew day, you can still struggle along with one less. It's not preferable, but it beats having to dump.
You can take this project and install it into pretty much anything you can drill a hole in (kettle, mash tun, whatever). One point that I will stress is...
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Tags for this post: DIY, heating, element, ULWD, electric, 120v, 1500w, kettle

The New Domain Name for our Community has been Chosen!

Posted by homebrewdad on 2/24/2015 at 12:37:45 AM

Last summer, when I first approached the charter member group with the idea of taking my personal blog and transforming it into a full community, an issue came up - namely, the domain name of "". The argument was that it was a fine name for one guy's blog, but that it probably wasn't the best choice for an inclusive community. Well, I was reluctant to make a change in this area; after all, I had built up my "brand", as well as some decent search engine indexing, over the previous two and a half years. The community, I reasoned, would benefit from the built in exposure that would come from this existing presence, and so, I pushed to leave things be.

Just over a month ago, we celebrated the transformation of from one guy's beer blog (plus a few odds and ends) into a full online community for homebrewers. While the response was pretty positive (we have grown to nearly four hundred members in this short time), the issue came up again. Once again, though, I was really reluctant to make a change.

Then, last week, I made my post about how homebrewing should be more friendly to women. This time, the subject came back with a vengeance. How could I claim to want to have a community for all brewers when I insisted on keeping a name that was hardly inclusive to women? The charter members laid it on pretty thick, arguing for a...
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Tags for this post: domain, name, community, voting, results

Homebrewing Needs a Woman's Touch

Posted by homebrewdad on 2/19/2015 at 11:11:18 AM


It goes without saying that I love brewing.  I find it to be such a versatile hobby - maybe you get your satisfaction from the creative aspect of recipe design.  Maybe you are more interested in the scientific angles, what with the various chemical and metabolic concerns related to fermentation.  Maybe you're a gearhead, and you get a sense of accomplishment from putting together the best/fanciest equipment for your brewery.  Perhaps you are a dyed in the wool DIY enthusiast, and your enjoyment comes from designing and assembling your gear.  Maybe you just happen to like beer.

I think that it's fair to say that, yes, a lot of factors enter into the motivations for brewing.  That diversity is really enjoyable to me, as it seems that it helps to foster a healthy hobby for everyone; people coming at the same problems from so many angles seems to create a lot of valid approaches to (and solutions for) problems that we all encounter.

However, there is one major area that I find homebrewing to be sadly lacking in diversity - and that is in gender. 

It's not like the historical precedent for female brewers isn't there.  In ancient times, brewing was almost exclusively the domain of women.  The same goes for medieval times; women handled the majority of brewing, as it was more of a household chore.  Even in colonial America, women were typically responsible for domestic task of brewing for a home.  In fact, the major impetus for the morphing of...
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Tags for this post: homebrewing, women, misogyny, hobby, brewing

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