Tuesday, October 30, 2012

How to make your own SRM tester

SRM, or the Standard Reference Method, is a widely adopted method of measuring the color of your beer. The values of color range from a 1 for a light pilsner to over 40 for a dark stout.  The BJCP style book uses the SRM color to identify the color that a beer of a select style should meet, and it is also a common metric that can be used for cloning a beer.  Having an accurate way to measure this can help you achieve a better product and take another step toward producing award wining beer.

SRM is ten times the log of the transmission ratio of blue light (420 nm to be exact)  The definition of SRM shows that dilution of the sample can be used to scale the SRM value.  (1)  Furthermore, Beer's Law (The scientist, not the beverage) shows that transmission is logarithmically related in the same way that SRM is calculated. (2)

There are methods in practice that use beers with known SRM values at different dilutions to make a set of SRM reference.  That sounds like a lot of work, and a waste of beer to me.

What I propose is using a dark liquid that almost everyone has in their house, and diluting it until it matches the color of the beer.  The amount of water needed to dilute the liquid can then be measured and from that the SRM value can be determined.

So what is this mystery liquid?  Soy Sauce!  The color content is very close to that of beer, and only a very small amount is needed for the test.  Both Kikoman's low sodium and regular have the same apparent attenuation of light.  Testing indicates that at a dilution of 38:1 the liquid has an SRM of 8.

Two glass 250ml Graduated Cylinders make a convenient way to measure the amount of added water, and to view the beer.  The graduated cylinder also makes a continent container for specific gravity measurements.

For 1/4tsp of soy sauce the ml of water required for SRM 1-20 is as follows:

For 1tsp of soy sauce the ml of water required for SRM 21-40 is as follows:


(1) http://en.wikipedia.org/wiki/Standard_Reference_Method
(2) http://en.wikipedia.org/wiki/Beer%E2%80%93Lambert_law

Sunday, October 28, 2012

Raspberry Cream Ale

Temperatures have dropped a little here in the North East, but not quite enough to lager.  So why not try a cold fermented ale?  The cream ale gets its character from two primary contributors.  The flaked corn gives it the creamy mouth feel, and the lower fermentation temperatures give it a refreshing cleanness normally associated with lagers.  It's time to make another raspberry beer because my wife and her friends loved the Raspberry Wheat we made recently, the only problem with it was that we didn't make enough. 

Batch size: 3 gallons
OG: 1.047
FG: 1.009
ABV: 5.0%
IBU: 15
Style: 20 Fruit Beer / 6A Cream Ale
Recipe type: All Grain

3lbs 12oz (1700 grams) American 6 Row
4 oz (114 grams) Corn, Flaked
4 oz (102 grams) Cara Pils (Dextrine Malt)
3 oz (76 grams) Special B
5 oz (136 grams) Corn Sugar (added at flame out)

Water Adjustments
1/8 tsp CaSO4 (Gympsom) to bring SO4 level to 24ppm
1/4 tsp CaCl (Calcium Chloride) to bring Cl level to 136ppm

Dough in at 122 and hold for at least 20 minutes while establishing a pH of 5.3 using lactic acid. 
1.5 hour at 149 degrees.

Hop Schedule
0.2 oz (6 grams) Challenger at 60 minutes (10.5 IBU)
0.15 oz (4 grams) Challenger at 10 minutes (2.9 IBU )
0.15 oz (4 grams) Challenger at 5 minutes (1.6 IBU)

Pitch100 billion cells required.  One half package of Safale S-04.

Fermentation63 degrees for 3 days, then 70 degrees for 4 days.
Rack to secondary.  Add 3 lbs of pasteurized frozen raspberries.

Bottling250 grams of corn syrup dissolved in 1 cup of water
(for corn sugar use 80 grams)


GristAmerican 6 row is the traditional grain used for this style although many recipes use 2 row.
Flaked Corn adds creaminess.  Flaked corn was chosen over other forms because it does not need to be cooked before the mash.
CaraPils adds body and aids in head retention
Sepcial-B is used in place of Caramel because of it's cake like flavor instead of taffy flavor.
Corn Sugar will lighten the body of the beer.  Using both corn sugar and carapils in the same recipe may seem like a conflict, but the result is the best of both worlds.  The head retention of the carapils and the lightness of the sugar.

MashTypical light body mash schedule

Hop Schedulestandard triple hop profile

FermentationFor an ale, this is the lower range for primary fermentation.  Bringing the temperature up to 70 degrees after most of the fermentation is complete allows the yeast to clean up by products.

BottlingStandard for about 2.5 volumes of CO2

Wednesday, October 24, 2012

Hoegaarden Clone Recipe

Batch size: 5 gallons
OG: 1.051
FG: 1.014
ABV: 4.9
Style: 16A Witbier
Recipe type: All Grain

4lbs 12oz Belgian Pilsner
4lbs 12oz Wheat, Light, Malted
1lb Dextrine Malt (Carapils)

Water Adjustments
1/8 tsp CaSO4 (Gympsom) to bring SO4 level to 24ppm
1/2 tsp CaCl (Calcium Chloride) to bring Cl level to 136ppm

1.5 hour ramp from hot tap water to sparge temperature.

Boil Schedule
1.75oz crushed (not ground) coriander at 60 minutes
1 oz Glacier at 20 minutes (15 IBU)
1 oz Glacier at flame out (1 IBU)
1 oz of sweet orange peel at flame out

180 billion cells required.  Prepare a 6 cup starter with a smack pack of 3056 Bavarian Wheat Blend Yeast, or use two smack packs.

64-74 degrees recommended for yeast.
Hold at 64 degrees for one week in a swamp cooler, then move to 70 degree ambient air environment for the remainder of fermentation.

3oz of corn syrup dissolved in 1 cup of water (1)
(for corn sugar use 1oz)


The recipe used today contains 55% Barley Malt, and 45% Wheat.  (2) The FG is about 4 points higher that would be expected given typical 75% attenuation, so 10% of the grist was changed to a dextrin malt.  CaraPills was chosen for it's light color.

The water in most places in the US is calcium deficient so only calcium salts are used.  The amount will very dependent on your water.  Adjust as needed to achieve the final levels.

The Hoegaarden web site states a 2 hour gradual rise to 170.  With the BIAB stove top setup I use this will be nearly full heat in the 4 gallon pot that I use to achieve this ramp rate.

Coriander does pretty well in the boil from what I have read in "The Home brewers Garden". 

Mr. Malty (3) was used to calculate the pitch rate. 

The low end of the fermentation range was chosen to aid with the higher than normal final gravity of this beer.  After primary fermentation is compete in about a week moving the beer to a warmer environment will allow the yeast to clean up any off flavors that may have been created during the primary fermentation.

(1) http://woodlandbrew.blogspot.com/2012/10/priming-with-corn-syrup.html 
(2) http://www.whitebeertravels.co.uk/celis.html
(3) http://www.mrmalty.com/calc/calc.html

Monday, October 22, 2012

How to make a beer recipe clone

When cloning a beer there are numerous places that you can gather information. 

1) The brewers website
2) your own measurements and experience.
3) The BJCP style guide
4) Sites that rate beers
5) forums and other online recipes.

The brewers website
If you start with the facts then the assumptions and estimations that come up later in the processes will not be as influential in your recipe.  Most brewers are very proud of the product that they make and will tell you quite a bit about what makes their beer different which almost always dives into some of the processes and ingredients used.  The Hoegaarden web site has several important clues on the recipe.  Hoegaarden is described as a classic wit beer with all of the ingredients grown in Belgium.  Belgium pale malt is therefore the likely the main base malt.  The mash is 2 hours and 30 minutes and during this time the temperature is gradually brought to 75 degrees C (167F)  If we assume a linear rise from room temperature the protein test (113 to 133) is about 30 minutes, and the saccharificatrion rest is about one hour, and the average temperature is 150 degrees.  This is a pretty standard mash for a light bodied beer.  As an alternative to converting this to a step mash, the same rate of 1.5 minutes per degree could be used to achieve a ramping mash.  The boil time is one hour which is very standard.  Citrus and coriander aroma and taste are mentioned. 

The ABV is stated as 4.9% which the OG can be calculated from if the FG is known.  Degassing the beer the FG can be measured. With the sample that I have it appears to be 1.014.  Knowing the FG and the ABV we can calculate the OG. 

OG = ABV / 131 +FG => OG = 1.051 

Alternatively, the gravity can also be calculated from the ABV and the number of calories.  From the OG and FG the attenuation of the yeast can be calculated. 

Attenuation = 1-(OG/FG) => Attenuation =72.5%

The attenuation is lower than a typical ale yeast, however fairly typical for some hefewisen and other yeasts commonly used for wheat beers.  Using the Whitbread Ale yeast from White Labs or Wyeast matches the attenuation, but Belgian Wit Ale seems to be more popular for this style.

Color can be compared to a BJCP color card to get an idea of the SRM.  Or if you are really geeky you can measure it using an blue LED with 430nm wave length and matching photo detector, but we'll save that for another time.  Using the BJCP card Hoegaarden looks like a 3 or 4.

When tasting Hoegaarden the citrus flavor jumps right out.  There is also a fermented fruit flavor which makes me think they are using more than just the rind.  There may be some pulp in this beer.  The hop flavor is very subtle, but what is there has a distinct citrus flavor and very little bitterness.  There are likely no bittering hops, and only flavor or aroma additions.  My nose and taste buds say citrus, and the brewers website says Belgium.  Glacier matches this criteria so it should work well

The BJCP style guide
We're lucky because the first example listed in the BJCP style guide for category 16A is ... you guessed it, Hoegaarden Wit.  Even if the beer you are cloning isn't listed, using the ingredients for the appropriate style will still be of great value.  From this information we gather the the grain bill should be 50% base barley malt and 50% wheat malt.  The other additions that are mentioned are the same that we saw on the Hoegaarden web site, orange peel and coriander.  Looking at the other spices mentioned, and a second taste of the beer, there may be some cummin in the recipe as well.  Hoegaarden doesn't exactly fit into the styles "vital statistics" with the FG at 1.014 where the style guide shows the high end of 1.012. The IBU's for the style are 10-20.  My taste buds tell me that it is at the lower end of this range.

Sites that rate beer
The two big ones, Beer Advocate, and Rate Beer, provide access to hundreds of different peoples tasting notes on this produce.  Perusing them confirms the ingredients that have been selected thus far.  It's also worth noting that the beer is described as sweet by many people.  With the low mash temperature the beer would typically be dry, not sweet.  Therefore there is likely some dextrin or other sugars remaining unfermented.  This could be from a malt high in dextrin such as crystal malt, or from Carapils which is also high in long chain sugars.  The color of Hoegarrden is very light so Carapils is more likely. Another way to increase residual sweetness is to select a yeast that does not attenuate well, and to ferment at colder temperatures. 

Forums and other online recipes
Between Homebrewtalk, Beer Smith, and a plethora of blogs and other sites the available information is overwhelming.  Choosing three to five recipes to compare will provide adequate information.  The next post will contain the clone recipe, and how it was derived. As a spoiler, I'll tell you I found an interview with the brewer!

Friday, October 19, 2012


The bitterness and sweetness balance of a beer is a complicated balance to achieve.  While these two tastes are each perceived by different receptors on the tongue, the careful combination of these two create a balance.  Too much sweetness without bitter will be perceived and cloying, and too much bitterness without sweetness will taste soapy.   Yet balance these two perfectly on the teeter-tottering see-saw that is beer and the two will be better than either on its own.

Dextrin Malts 
Adding high dextrin malts like Caramel or Crystal malts will leave the beer with a higher final gravity.  Steeping crystal malt after the mash will produce 25% less ferment-able sugars.  (1) This not only give the beer a thicker mouth feel, but also adds to the final sweetness of the beer.   High final gravity can also be achieved by mashing at higher temperatures.  For every degree Fahrenheit above 155 the final attenuation of the beer is lowered about 2 percent.   (2) In general 1%-2% is normal to add color to a beer.  5% will add noticeable sweetness and caramel taste.  10% can easily be too much if not balanced with hops, or keeping the Chlorine ions low.

On the bitterness side the most apparent factor is the hop level measured in IBU's.  The bitterness from hops can easily be adjusted during the boil of the brewing processes by changing boil time and amount of the hops.  After the wort has cooled, the gravity sample can be tasted and dry hops can be added to further adjust the flavor, but because the wort will be high in sugar content at this time it may be hard to judge if more bitterness is needed.   Keeping the IBU’s around 20 will make most people happy although light beer drinkers may prefer less than eight.  If less sulfates are in the brewing water the IBU value can be higher without tasting harsh.

After fermentation is complete most of the sugar will have changed to alcohol. Higher alcohol content will mask some of the sweetness of the beer.  Have you ever tasted a cocktail mix without the alcohol? They are extremely sweet, yet when the alcohol is added they taste much less sweet.  The ABV to sweetness balance works it’s self out pretty well in beer because the alcohol content is directly proportional to the amount of sugar that is converted.  So bigger beers have more final sugar, but also have more alcohol to balance it.

Before bottling the bitter sweet balance can be adjusted using salts.  It's very easy to overdo it here.  Remember these are called brewing SALTS, and if overused you will have beer that tastes … well… salty!  One half a teaspoon of salt in a five gallon batch is normally plenty.  Sulfates (SO4) will enhance the bitterness while chlorates (Cl) and sodium (Na) will enhance the sweetness.  Sodium can often cause a metallic taste in the beer so common table salt (NaCl) is often not used in beer.  There are a number of good sources online that can be found by searching for “brewing water chemistry.” 

The final adjustment to balance is carbonation.  The higher the volume of CO2 dissolved in the beer the more bitter the beer will taste.  If you compare a flat soda to a carbonated soda the difference in taste is very apparent.  Although CO2 content does play into the bitter sweet balance it is likely the least noticeable.  Considering it for taste should be secondary to mouth feel and style.

Finding this balance can take time.  If you are starting a recipe from scratch it is easy to miss your mark by a mile.  If you start with a reliable recipe you are bound to get good results. 
(1)    See post from nilo on Homebrewtalk.com 03-09-2011, 11:55 PM http://www.homebrewtalk.com/f128/testing-fermentability-crystal-malt-208361/index11.html

Thursday, October 18, 2012

Priming with corn syrup

Getting sugar to dissolve can be difficult, and if you've every worked with dry malt extract you know how messy it can be.  The easiest priming sugar that I have found is corn syrup.  It dissolves easily in water, is available without a trip to the local home brew store, and ...

It's cheap!

The brand that I buy is 12g of sugar in 2 tablespoon.  To carbonate 5 gallons of beer at 2 volumes of CO2 3 oz of corn sugar is required.  That's 87 grams of dextrose.  So that's 14 table spoons, or 0.9 cups. Each cup of corn sugar weighs 326 grams.  Therefore, 295 grams of corn syrup are required to carbonate 5 gallons of beer.  Whew!  I'm glad that math is over.  Here is a table so that no one has to go through that again.

volumes of CO2








Tuesday, October 16, 2012

Not just sanitized, but sterilized!

Short of having an autoclave in your home, this is by far the easiest way to prepare bottles that I have found.  It's better not to use soap to clean your bottles.  The soap will leave a residue that is detrimental to the head retention of the beer.  Once the bottles are rinsed out they can be placed in the oven.  The racks in my oven allow over two cases of bottles to be sterilized which is perfect for a five gallon batch of beer.  Once the bottles have been laid out inside set the oven to 350.  After 90 minutes turn off the oven, and the next day the bottles will be cool and ready to fill with beer.  Placing foil over the tops of the bottle will keep most of the air inside meaning that the bottles can even be used at a later date as long as the foil stays intact.

How It Works

Autoclaves work by a combination of heat and pressure to more rapidly kill all micro organisms, but dry hear alone can also be used to effectively sterilize glass.  This processes is know as Dry Heat Sterilization.(1) 


Sunday, October 14, 2012

Mash Temperature and Thermometers

The temperature of the mash contributes to thickening the body of the beer more than any other factor.  There is a very narrow window of temperature that changes the ferment-ability of the wort.  For every degree Fahrenheit above 152 the wort ferments 2% less.(1)  At 160, only 5 degrees higher, the enzymes that convert starch to sugar can be destroyed to the point that they will not complete the conversion of the grain into ferment able wort.  Not only is even temperature of the mash critical for this reason, but accurate temperature is very important as well.  In my kitchen are three thermometers, and the all measure boiling water as being at different temperatures.  Water, at one atmosphere with no additions, boils at 212 degrees Fahrenheit by definition.  The three thermometers measured 213, 216 and 217 degrees!  This thermometer from the grocery store was off by 5 degrees.
The difference between 75% efficiency and 48% efficiency can be 5 degrees.
While this may not sound like a tragedy, it can be.  According to Greg Noonan, author of "New Brewing Lager Beer" For a light beer the target Scarification temperature is 150 degrees, and for a malty full bodied beer the target is 157 degrees.  That's only a seven degree difference from light to full bodied.
The last three mashes I brewed I targeted 158 degrees to enhance the body of the beer.  Because my thermometer was reading high by 5 degrees the actual mash temperature was 153 degrees which is the target for a typical ale.  That's not the thick malty style I was going for.  Had the target been toward the low end, to create a highly ferment able wort, it is likely that there would not have been complete conversion.  This would leave starch in the wort as well as create a low initial gravity and a low efficiency. 
So what can you do about it?
1) Buy a better thermometer.    Pens style thermometer seem to be more accurate than the oven style out of the box in my experiance.  The Tru Temp that my wife purchased is very accurate. If you want to be certain then purchasing a thermometer that has calibration data will let you know how far it is off.  Many brewers swear by the Thermapen.  It is pricy, so I haven't tried one, but this does have calibration data.  +/-2 degrees F. Also, looking for something with a Type K or J thermal couple is probably a good place to start. 
2) Compensate for the thermometers inaccuracy.  The two easiest known temperatures to measure are boiling and freezing.  Mash temperatures are closer to boiling.  So, if you boil water, and live near sea level, you should measure 212 degrees.  If you know how many degrees off your thermometer is you can correct the value that is read.
3) Calibrate your thermometer.  This is most easily done with an oven style thermometer than can be unplugged.  If you're an electrical engineering geek like me, this is a fun little project.  Measure the resistance of the thermal probe at freezing and boiling.  record what the thermometer reads under these conditions.  Calculate the required trimming potentiometers to add in parallel with the thermal probe and in series.  Trim the large parallel resistor to make ice water read 32 degrees, then trim the small series resistor to make boiling water read 212.  Check again at 32 and repeat if needed.  It looks like for my oven thermometer a 10Meg trim pot in parallel and a 1k trim pot in series will do the trick.

(1) http://braukaiser.com/wiki/index.php?title=Effects_of_mash_parameters_on_fermentability_and_efficiency_in_single_infusion_mashing

Friday, October 12, 2012

Brew House Efficiency

Circuit Diagram

Rt is the thermal probe.
Rp is the variable portion of the parallel resistance (10 Mega ohms for the thermometer used)
Rf is the fixed portion of the parallel resistance.  (5.2 Mega ohms for the thermometer used)
Rs is the series resistor. (1 kilo ohm for this particular thermometer)

(You can buy this same thermometer that was used with this circuit at the bottom of this blog post)
Resistive thermal couples such as those used in most kitchen thermometers all work the same way.  As temperature increases resistance decreases,  conversely as temperature decreases resistance increases.  The resistance is exponentially related to temperature.

This circuit might work for you as well, but there are no guarantees. 

At boiling the thermocouple measured 6.19 kilo ohms, and the meter displayed 216.1 degrees which is 4.1 degrees high.  In near frozen ice water the thermocouple measure 326 kilo ohms and the meter displayed 30.0 degrees which is two degrees low.

The easiest way to figure this out may be to plot the effects of different resistors in Excel, however you can calculate the values if you would prefer.

With these data points an exponential fit can be derived.

resistance(k ohms) = 617.64e-0.021 temperature

From this fitting equation the required resistance can be calculated for the temperatures that were displayed by the meter.  We can calculate the resistance needed to display 32 degrees.  This is 315k ohms.  the parallel resistance in order to make 326k ohms into 315k ohms is 9.33 mega ohms.  The same type of calculation can be done for Rs.  Note that the circuit would be slightly different if correction in the other direction was needed.

The parallel resistor will reduce the resistance of the thermal couple making it appear to the meter that the temperature is actually warmer than it really is.  The series resistor will increase the resistance making it appear colder.  It may take some toying with the values to get it working.  The series resistor will have more effect at hot, and the parallel resistor will have more effect at cold.  This is because of the relative size of the resistors.  When Rt is large, even the full range of change of Rs is negligible, however Rp is close in size to Rt in this condition and will therefore change the resistance more.  Now, when Rt is small, the large parallel resistance is effectively an open so it will have little effect, however Rs is close in size so it will change the total resistance sustainably.

Thursday, October 11, 2012

Mash pH

It's hard to find any good rules of thumb out there for how much lactic acid to add to the mash to adjust the pH, and there's good reason for that.  The starting mash pH is very dependent on a number of complicated factors and interactions.  The main driver of the starting pH is the pH of the grain itself and the dissolved minerals in the water interacting with the grain.  These will stabilize at some pH value when you have thoroughly stirred in your grains.  How this all works is... complicated, and you really don't need to understand it to brew great beer.  The fact is you really aren't going to know what your pH is until you get to dough it.
...but there is an easy way to figure out how much acid to add after dough in!
Once you have doughed in you can then measure and adjust the pH.  While the starting pH is hard to determine, the strength of  the buffering agent is notBecause there are so many more dissolved particles of grain in the water than dissolved particles of minerals, the buffer power of the mash is almost entirely driven by the amount of grain that you have added to your water.  The more grain added to the water, the stronger the buffer.  The stronger the buffer, the more resistant to change the pH will be.  Because it is the grain driving the strength of the buffer, the pH change of a volume of acid will not be effected by the amount of water in your mash tun.  Meaning that whether you have 2 gallons or 20 gallons of water, it will not affect how much 1mL of acid changes the pH.  The fact that the mash pH is not related to the volume of water may seem very strange, so let me explain further.  pH is a function of the ratio of positive ions to negative ions.  The water itself has very few ions, so while it does have a pH value, it is a very weak buffer.  The grain, however, has tons of particles that dissolve into the solution, meaning thousands of times more ions than the minerals in the water.  Therefore, the ratio of ions is driven by the grain, not the water.  To beat a dead horse, because this was such a light bulb moment for me, let's use some number to explain it one more time.  If the water had equal number of ions, five positive and five negative, (5+, 5-)  the ratio would be one to one (1:1).  If we add grain with ten thousand positive ions, and five thousand negative ions (10,000+, 5,000-) the ratio is now ten thousand and five to five thousand and five, (10,005:5,005) or about two to one (2:1) which is roughly the same as the grain alone.
Using the EZ-Water calculator, (1) and several brewing experiments, I have come up with a simple equation:

 mL of lactic acid needed = change in pH * weight of grain in lbs

For 10 lbs of grain you would need 1mL for every 0.1pH point.
For 5 lbs of grain you would need 0.5mL for every 0.1pH point
This is for 88% lactic acid solution which seems to be pretty common. To make measuring simple without a pipette use a normal eye dropper.  It will hold about 1mL and each drip is about 0.1mL

pounds of grain

milliliters of 88% lactic acid to add  to achive a hot mash pH of 5.2

pounds of grain
61/23/43/411 1/41 1/41 1/21 1/2
5.91/21/23/43/411 1/41 1/41 1/2
hot5.81/41/21/23/43/4111 1/4
mash5.71/41/21/21/23/4111 1/4

teaspoons of 88% lactic acid to add to achive a hot mash pH of 5.2