Tag Archives: Equipment

Easy Yeast Starters

Have I ever mentioned that managing fermentation is really important to making great beer?  Sure I have.  And I know that one of the biggest challenges to most home brewers is controlling fermentation temperature.  Well, maybe you don’t have a dedicated fermentation chamber but you can certainly make sure that you pitch the correct amount of yeast.  Unfortunately, much like IBU calculations, figuring out the correct yeast pitch relies on a bit of guesswork.  Still, a little knowledge can be a good thing.

First, how much yeast is needed?  The simplest number is about 1 million cells per milliliter of wort per degree Plato.  A more detailed recommendation is pitching 750,000 cells per ml per °P for ales and 1.5 million cells per ml per °P for lagers.  For ease I am going to use the 1 million value.  A 5 gallon batch is 18.9 liters or 18,900 milliliters.  This means that we need 18.9 billion cells per degree Plato.  So for a beer at 10 °P (1.040) this means that 189 billion cells are needed.

The challenge for the brewer is that your basic White Labs tube or Wyeast smack pack only promise 100 billion cells.  Despite any claims of being “pitchable” the volume of cells in these packages are not truly sufficient, one needs about twice as many yeast cells.  The easiest way to double the volume of yeast cells is to pitch either a White Labs tube or Wyeast pack into make a one liter volume of wort and let it ferment out.

Here is an easy solution: get some empty two liter soda bottles, wash them and sanitize with your favorite sanitizer.  Add one liter of wort and and the yeast, and cap the bottle.  Shake like crazy, then crack the cap and squeeze the bottle until the liquid is near the top.  Set in a nice warm place and let it do its thing. The great thing about 2 liter pop bottles is that they are incredibly strong.  Once the yeast begins to work and liberates some carbon dioxide, the bottles will become quite firm to the touch.

OLYMPUS DIGITAL CAMERACracking the lid allows some of the CO2 to escape, and you can once again squeeze the bottle before resealing.  Shake again to redistribute the yeast.  it makes a great substitute for a stir plate.  And, when the yeast has finished growing you can put the whole bottle into the fridge until it is needed.  it is safe, sealed, and secure.

New Brew Tool

If you like to cook, then like a brewer you know the importance of taking fast and accurate temperature readings.  The best kitchen tool for this is the Thermoworks Thermapen:

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The thing I love about this tool is that it reads the temperature in a matter of a few seconds.  This is important when yo have your head in a hot oven or over a smoky grill.  With a price approaching $100 it is not a cheap tool, but it is very useful.

Unfortunately it does not work as well in the brewery.  The short probe only reaches the top few inches of the mash.  But even worse, the Thermapen does not like humidity.  In my experience, after a few uses over a steaming wort the unit just goes haywire.  (Lucky for me, it dries out nicely and continues to work!)*.  So I asked Santa if she could bring me a better thermometer for brewing.  And she did!

In addition to the Thermapen, Thermoworks makes a number of other models of thermometers.  Here is the one Santa brought:

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This is called their Two Channel Thermocouple with Alarm.  No fancy marketing terms here.  This unit reads the output from two different Type K thermocouples (sold separately).  As the name implies, the first channel allows you to set high and low limits with the alarm sounding whenever the temperature falls out of that range.  These units are useful for grilling and smoking, too.  One probe can monitor the oven or grill temp while the second probe can be inserted into the meat and warn you when the correct temperature has been reached.

But for brewery use I have found a flexible, silicone coated and tipped probe to be useful.  Unlike a meat probe, this thermocouple has no metal tipped sheath.  In the past I have had thermocouples short out due to water entering the probe at the junction where the sheath ends.  The following picture shows how I have been using the new probe: I thread it through a short piece of copper tubing, which then allows me to position the probe anywhere I want inside the mash:

OLYMPUS DIGITAL CAMERAI can now continuously monitor my mash temperature.  I find this particularly useful when making brew-in-the-bag mashes: whenever the temp drops out of range the alarm goes off and I add a bit of heat from the burner. Small mashes tend to lose heat quickly, so this method helps me keep my mash temperatures fairly constant.

And as a free gift, Thermoworks threw in this free little thermometer:

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It is small, the probe is only 2 inches long or so, but it is great for measuring the temperature of the grain before mash in.  Thanks!

* Thermoworks now makes a moisture resistant Thermapen.  I cannot say how well it works, but my experience with this company has been good so I would anticipate the best.

It’s in the Bag

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It was a cold start in the LittleBoy Brewery this morning.  The second full day of winter brought cold dry air after a little dusting of pre-Christmas teaser snow.  There will be no White Christmas.  But there will be a batch of black stout in the fermenter.

The recipe today is a simple dry stout – mostly Maris Otter malt with a good portion of flaked and roast barley. However the brewing method is a little different: Brew in a Bag.  It is a process I have experimented with before, but I am revisiting it.  This procedure requires the services of a mesh bag large enough to fit into the brew pot.  I found mine at the local mega hardware store, in the paint department.  Five gallon size bags are sold for the purpose of straining paint, I assume before it is used in an airless sprayer.  No matter, because it is just the perfect size to fit in my five gallon brew pot: OLYMPUS DIGITAL CAMERA

Making a BIAB beer is pretty simple.  My version works like this.  Add your strike water to the boil bot and heat to the appropriate temperature. Crush the grain and add it to the boil pot.  Mash for however long you prefer, then top up the boil pot and remove the bag, allowing all of the sugary goodness to drain into the boil pot.  If needed, add a bit more water to achieve the correct pre-boil volume, then boil away. Here is my BIAB mash, in progress:OLYMPUS DIGITAL CAMERA

Now I make this even more complicated than it needs to be.  Many BIAB brewers just add all of the required water to the mash.  I have not done this, but all accounts I have heard suggest the mash converts just fine.  (And you thought there was something magical about 1.25 quarts of water per pound of grain.)  Once the mash is done they just lift, drain, and boil.  Nice and easy.

So if you haven’t thought much about this, here are the down sides to the process.  You may need a larger brew pot.  The grain and water obviously take up much more room that just the water.  Finding a larger mesh bag can be a problem.  My wife, who is handy with the sewing machine, made me a bag that fits my 10 gallon brew pot. Which brings us to the second challenge: the wet grain bag for a large brew can be a little heavy, and it needs to be left hanging over the brew pot until it drains.  This can require a little McGyver action in the brew house.  The last issue is a little more subtle: a bit more grain mass gets through the mesh bag than typically gets through the grain bed in a traditional mash.  So there is a little more solid matter in the brew pot at the end of the boil.  Maybe a little more wort loss.

But the process has a lot of up side potential.  It saves cleaning out a second vessel.  And it is quicker:  the “sparge” consists of   simply lifting the grain bag and letting it drain for a few minutes.  And it seems like it should be a very predictable way to brew.  In future posts I will delve a bit further into the process and explain how I calculate my BIAB batch parameters.  Because you might find this process works well for you.

Chill, Part 3 (A better way)

Probably the best way to conserve chilling water is to brew in the winter, when the water from my tap is 6° or 7° C.  Of course I like to brew year round and in many places the water temperature never gets that low.  So after abandoning my pre-chiller concept it was time to pay a visit to the Cheap Chinese Tool Store.

Do you have a Cheap Chinese Tool Store near you?  Well, mine is not really called the Cheap Chinese Tool Store, it goes by a name that suggests a deep, protected body of water where ships might anchor to unload cargo and the second part of the name rhymes with crate.  Let me state for the record that I have no issue with the Cheap Chinese Tool Store.  It is full of cheap tools. A set of screwdrivers for $5, a bar clamp for under $2, an 18 volt electric drill for $25.  These are prices you do not see at your local mega box home improvement store.  Still I feel slightly dirty when I buy from the Cheap Chinese Tool Store.

The item from the Cheap Chinese Tool Store that forms the basis of this article is the cheap garden water fountain pump.  For less than one Alexander Hamilton, I walked away with a low output submersible pump:

The job of this little pump is to transfer ice cold water through the wort chiller.  I was concerned about whether it would have enough head pressure to do it, but it managed (barely).  It a perfect world one would spend the money to buy a pump with enough output to pump the water from the ice bucket through the chiller and back to the ice bucket.  Well, this one does half the job.

The procedure is as follows.  At the end of boil I run tap water through the chiller as normal.  It doesn’t take long for  the wort temperature gets down to say 50° C (about 120° F).  I use quick disconnects to quickly change the chiller input from the tap to the pump submersed in a an ice bath.  Plug in the pump, and the cold water flows down through the chiller and into a small bucket on the ground.  As the bucket fills, I simply pour it back into the bucket of ice water.  If necessary I add more ice to keep the water well chilled.  Is it perfect?  No.  Is it cheap?  Yes !  Does it work ? Yes!!

With a little patience this setup can easily lower the wort to lager pitching temps with a minimum of wasted water.  And of course I catch the initial water output in my mash tun, as it is scalding hot and is excellent for washing the pots and pans. It is almost perfect.  But alas, it is not the best that can be done.

Milling Around

The incident with the stone sparked the idea to talk a little about my motorized grain mill.  It seems like ages ago when I started home brewing, in reality it was 1997.  Compared to stories I have heard about the true pioneers in homebrewing (like back in the late 1970s and through the 1980s) 1997 was a golden age for homebrewing.  Local homebrew shops carried a variety of ingredients and the internet provided a resource for brewing information (although sometimes a quite dubious one).  Liquid yeasts and fresh hops were both readily available, a reality that early homebrewers could not take for granted.  Still, the variety of ingredients and the scope of knowledge that was available was considerably less than today.

Back in ’97, after just a few batches of beer, I knew I wanted to brew all grain recipes.  There was, and still is, an undeserved stigma surrounding beers made from extract and I fell under the spell of that stigma.  I dabbled with partial mashes until my eight brew, which was an all grain lager.  My homebrew shop had a mill and offered free milling, but I knew I wanted a mill of my own.  At that time there were only three readily available options for roller mills (the Corona Mill, which is a plate mill, was and still is available).  One was the Valley Mill, and it was the one my local shop used.  It was a tall skinny thing, but most the feedback I ever read on it was positive.  It was an adjustable two roller mill as I recall.  The second commonly available mill was the Schmidling Maltmill.  Unlike the Valley Mill, this product is still available today and it is known to be a rugged and durable mill.  The base model featured a non adjustable gap, though just like today there was an adjustable option.

The last readily available option was the Phil Mill.  Offered by Listermann manufacturing, it is slightly different than the typical roller mill.  Instead of two rollers, the Phil Mill is constructed from a single roller and a curved plate.  The roller crushes the grain against the curved plate, and a small bolt adjusts the gap between the plate and the roller.  This mill is compact, compared to its competition, and at the time it was significantly cheaper.   The design was not without its detractors.  In particular the “roller and plate”  design was held in contempt by some, since it was not a true two roller mill.  I gave this issue some consideration, but after reading a few independent reviews I opted for the Phil Mill.

The first few years that I had this mill I used it in both hand cranked and drill powered mode.  Hand cranked mode can be tough, as this mill has a somewhat  low throughput. This means lots of cranking  and maybe a few blisters. I also had an old 3/8″ drill which I used to power he mill at times, but this was not satisfactory.   It was underpowered and it was difficult to control the speed.  I muddled through.

About five years ago our old clothes dryer gave up the ghost, at least my wife wanted a new one.  So I took the opportunity to harvest organs from the dying patient: the motor, belt and controls.  At first I looked for a shorter, smaller belt but I had little luck, so I design a mill that could utilize the long belt that came with the clothes dryer:

The motor is located at the bottom, and the long belt is visible just to the left center.  The two liter green plastic jug is the grain hopper, and the on/off starter switch is on the panel just below.  Here are a few more close ups:

Close Up of the Mill and Pulley

The above photo is from the opposite side; it shows the Phil Mill up close.  The small machine screw exiting the bottom allows for the gap adjustment.  You can see the home made pulley and drive belt.  It is attached to the mill shaft via a neat bushing I found on McMaster-Carr: it slides onto a drive shaft and when tightened it both grips the shaft and expands in diameter.  So not only does it tighten on the shaft but the expansion causes the wooden pulley tighten on the bushing.  Neat!

The Dryer Motor

The above photo is a little close up of the motor.  In a bit of design brilliance I mounted the motor on a hinged base. This allows the weight of the motor to hold tension on the belt.  The beauty of this setup is that if the mill becomes jammed (like from a rock) the belt will easily slip on the drive pulley.  The downside of the design ii that I sometimes need to exert a little downward pressure on the base in order to make prevent the belt from slipping.  It is a reasonable compromise.

Output Chute and Pulley

This last photo shows the mill drive pulley and the output chute from the mill.  You can see the small hook used to hold a small plastic bucket inside the stand just below the chute.  Each bucket can hold 4 kilograms of grain, and if I am crushing a large amount of grain I have an rigid aluminum dryer vent pipe (about 4 inches in diameter)  that I can put over the chute to divert crushed grain to a larger bucket on the floor.  The pulley was home made out of fiber board.  Cutting a circle was pretty easy using a band saw.  I got pretty lucky when I cut the groove in the pulley that the belt rides in:  I just eyeballed the height of my table saw blade and the position of the fence. I just wanted to quickly build the thing and see if the pulley would work.  Ss it turned out I made a perfect fit the first time.  It is probably lucky I chose not to measure, I would have screwed it up

So that was it and it has worked pretty well for five years.  I normally crush my grain twice, the first time I set the bolt so that it just touches the plate inside.  Before the second pass I give it about a quarter turn, and I get a good crush.  If my recipe includes wheat I usually crush it separately, and maybe do three passes on it so as not to strain the equipment.

Alas, the Phil Mill is no longer manufactured.  Mine has provided good service and hopefully it has a few more batches of beer in it!

Chill, Part 2 (how not to do it)

In the last post on this topic I talked about my concern that the process of wort chilling can be a huge waste of water.  Well, waste might not be a fair term, but it can take a significant amount of water to cool the wort, and for many people this water goes straight down the drain.  Water is a precious resource, and I fear that often our society takes it for granted.

As I proceeded in my brewing career I realized that the temperature of the water coming from my tap had a huge impact on chilling times.  In the winter, the tap water in Western Pennsylvania can drop down to 5 °C or so.  Wort chilling proceeds pretty quickly at this temperature. In the summer the water can reach 20 °C or higher.  I like to pitch many ale yeasts at 16 to 18 °C, and if the chilling water is at 20 °C then one has no hope of reaching the desired pitching temperature.  Lager temps?  Yeah, funny.

So what I decided I needed to do was come up with a way to lower my incoming water temperature year round.  So I built this pre-chiller contraption:

The coil on the bottom came from a ice maker kit.  The remainder of the device was carefully sweated together.  Egads, there is probably $20 worth of copper in this thing.  Oh well, it was cheaper then.

So how does it work?  The coil is inserted into an ice bath, preferably in a cooler as shown.  The valve in the center is initially set wide open. The water from the tap comes in the fitting at the upper right and exits at the upper left.  Since the “path of least resistance” is through the valve (rather than the narrow tubes in the coils), the bulk of the water flows directly through the pre-chiller. This is fine, as even relatively warm tap water removes a significant amount of heat from near boiling wort.

Once the wort gets down to 40 or 50 °C (OK, 100 to 120 °F) the valve is closed.  This forces the water to go through the coil (in the ice bath).  I never measured the temperature of the water coming out of the chiller coil.  In the ice water bath was at 1 or 2 °C, then I figured the water could get down to 5 °C.  So, how did it work?  OK, I guess.  I did have to keep replenishing ice in the ice bath, but it did seem to be effective, especially when trying to lower the wort temperature to lager yeast pitching temps.  But it required a number of connections to be made, and each connection was a possible source of a leak.  So after a few tries with this, I gave it up. But I did not give up on trying t use less water. More to come.

Chill

I have never liked the process of chilling the wort at the end of the boil. You have to do it, of course, but it comes after creating the recipe, cracking the grains,  mashing in and boiling, which are all much more fun and rewarding aspects of the brewing process in my opinion.  In addition one usually stands in front of a wide open boil kettle just waiting for airborne contaminants to land in your carefully prepared wort. It is a situation that is not conducive to the “relax, don’t worry” mantra of the home brewing community.

Even more disturbing, chilling the wort involves taking beautiful, pure, clean drinking water and using it once and often just sending it down the drain.  Obviously you can recycle.  In the past I have recaptured the hot water from the chiller (I use an immersion chiller) for use in the clean up process, but there always seems to be much more water than is really required to do the job.  In the summer you can capture the water and use it for watering the garden, but trust me, during January in Pittsburgh the need in that regard is pretty low.

I have been on a trek to decrease water waste in my brewing while not compromising the quality of the suds. I have tried a few ideas, and I thought I would share what I’ve found. But since I am a geek first, let’s talk some numbers in order to get  an idea of the magnitude of the problem.

Heat can be transferred in a number of ways.  Conduction might be the most easily recognized form.  Put your hand on a hot stove?  Heat conducted from the stove to your hand activates the nerves that causes your hand to recoil; the heat conducted into your hand might cause redness or even blisters.  Heat transfer by radiation is also a very common experience.  Stand outside on a sunny day and you will feel the warmth of solar radiation warming your body.  In fact you might begin to sweat, and then heat will be transferred from your body by evaporative cooling.

In chilling wort, the principle method of heat transfer is conduction.  Heat energy in the wort is transferred to the copper and then to the water flowing through it.  The water exits the chiller carrying heat away.  The rate of heat transfer depends on the temperature difference between the wort and the water and that is why the wort temperature drops rapidly in the first few minutes of chilling and then slows noticeably, especially as the wort temperature approaches the temperature of the water leaving the tap.

Water (and wort is mostly water) can hold a lot of heat energy.  The ability of a substance to store heat is called heat capacity, and it is determined by measuring how much energy must be put into a material in order to raise its temperature by a set amount (usually one  Kelvin, which is essentially one degree Celsius). Just for reference, compare water and steel.  It takes about ten times more energy to raise the temperature of water, versus steel, by one Kelvin (4.2 Joules versus 0.4 Joules for steel).   If you want to compare various materials here is a link to a table of various materials and their heat capacities.

But this still doesn’t get to the question of how much energy really needs to be removed from the wort in order to reach pitching temperature.  Suppose you have one kilogram of water at boiling temperature (100° C) and you want to cool it down to 20° C  (that’s 68° F for you non metric types, about typical ale pitching temperature).  If your tap water was at 10 °C, how much would you need in order to cool your wort?
One can get a good approximation by approaching this as a mixing problem.  If you mix two liquids together, the final temperature is given by the following equation:

Final Temp =  Tf = (T1 x M1 + T2 x M2) / (M1 + M2)

Where T refers to the temperature of the liquids and M to the mass.  In reality this equation is a little more complicated if you are using materials of different heat capacities, but since we are using water in both cases we can use this simplified version.

What we really want to determine here is M2.  By using a little algebra we can rearrange the equation to solve for M2:

M2 = M1 x (T1 – T) / (Tf – T2) = 1 x (100-20) / (20 – 10) = 80 / 10 = 8 !!

So in order to cool down one kilogram of wort you need about 8 kilograms of cold water.  Applying that factor of eight we can estimate it requires about 40 gallons of water to cool down 5 gallons of wort.  That seems like a lot, and I know that some heat is lost from the wort due to evaporation and radiation, but still that is a significant amount of water.

Can we use less?  Certainly, and I aim to tell you how I am doing it.