55% Efficiency after Batch Sparge

[blair.streit]

@jmitchell3

@SPAMR

Disclaimer: yesterday was my first time brewing all grain. I have only read about the process, and watched a few contradicting YouTube videos.

In short:
I was hoping to achieve 72% efficiency but ending up hitting only 55%. Thankfully I was originally trying to brew an Imperial IPA, but ended up brewing an IPA instead.  ;D

The process:
15# of grain and 4.5 gallons of water in a 10 gallon SS Brew Tech mash tun.
Strike water was 170*, the grains were steeped for 60 minutes at ~154-149 by the end.
Batch sparged with 3.3 gallons of water which was inserted into the mash tun at 195*
Mixed grains and emptied into the brew kettle.

Any advice on what/where I went wrong?

Next time I am going to try fly sparging since I have the attachment for the mash tun. The only reason I didn’t use it last night was because I have t built out the HLT yet…

55% is too low for mash efficiency. What was the volume of wort you collected at 1.060 SG?  The first three areas of focus are:

1. measurement precision and accuracy when taking volumes and SG readings.
2. grain crush. The kernels should be broken ideally with limited/minimal hull shredding.
3. mash ph. Did you test your mash ph? Did you do an iodine test for conversion?

The other one I see a lot that yields mid 50’s is essentially no sparge. I did this once with a  “fly sparge” where I never actually drained the mash tun before adding more water. This was one of my early all grain batches and in a rush I just started adding hot water as soon as my Lauter started. So basically I was just diluting my first runnings, but never closed the valve to stir and “rinse” the grains for a true sparge.

At that point I realized that while I was able to speed read “How to Brew” in about an hour, I didn’t really understand what I was doing [emoji3]

[system]

@Saccharomyces

Well, I spent a few minutes reading Kai’s wiki, and all I can say is that the KISS principle is nowhere to be found.  Part of the problem is that Kai works with the metric system, which is not as straight forward as working with English measurements when brewing.

For those who are open to new ideas, a quick and dirty way to determine extraction efficiency is to take the gravity of the cast-out wort, convert it to points, multiply that value by the total volume of the cast-out wort in gallons, divide by the weight of the grist in pounds, and then divide by 36.

sg_to_points = (gravity - 1.0) * 1,000

The above conversion can be accomplished in one’s head by making the number to the right of the decimal point in an S.G. reading an integer (i.e., whole number)

Example

1.065 = 65 gravity points

extraction_rate_in_points_per_pound_per_gallon = gravity_points * cast_out_wort_volume_in_gallons  / grist_weight_in_pounds

quick_and_dirty_extraction_efficiency = extraction_rate_in_points_per_pound_per_gallon / 36

The value 36 is derived by multiplying the gravity points in a pound of pure sugar (45) by 0.8 (a dry basis, fine grind value of 80%).  Kai states that the 80% value is more like 77% in practice due to moisture pickup; therefore, we could adjust the value 36 down to 34.65 (35).  However, the value 36 is good enough in practice.  The reason why we can treat the mash as being 100% base malt is because the base malt dominates the total gravity points to an extent where it swamps out the lower yielding malts.

Remember, all efficiency percentages are merely approximations due the fact that we do not know the actual maximum yield for any given malt, which it why I stop at points per pound per gallon.  I do not care what my efficiency numbers look like.  I want to know how much extract I can yield from a given amount of malt.  Points per pound per gallon (PPG) gives me a number that I can scale up or down.

My average extraction rate in PPG is 30, that is, the extract from one pound of grain in a one gallon solution has an S.G. of 1.030.  All I need to do to determine the amount of grain that I need for a batch is to divide the target gravity in points by 30 and then multiply that value by the batch volume in gallons.

target_gravity = 1.056

batch_volume = 6 gallons

grist_weight_in_pounds = 56 / 30 * 6 = 11.2 pounds of grist

This system makes formulating a recipe brain dead simple.

For example, SNPA has an S.G. of approximately 1.053.  Using the PPG value above, I need to use 53 / 30 * 6 = 10.6 pounds of malt.

Let’s assume that SNPA is 97% base malt, 3% British C60.

base_malt = 10.6 * 0.97 = 10.282
c60 = 10.6 * 0.03 = 0.318

In practice, I would round 10.282 down to 10.25 and 0.318 up to 0.375 to make weighing out the malt easier.

Do you use a similar “low tech” method for hopping as well?

For the visual learners out there: http://tinyurl.com/gwlhy9t

[Saccharomyces]

Do you use a similar “low tech” method for hopping as well?

Believe it or not, I still work in Amateur Alpha Units (AAUs, a.k.a Amateur Acid Units) most of the time.  AAU is the British acronym for Homebrew Bitterness Units (HBUs).  I will calculate IBUs if someone wants the value, but IBUs are overkill in most recipes.  There is one area in home brewing where going through the trouble of calculating IBUs is worth it for me; namely, cloning.  However, I use AAUs within my home brewery for most of my recipes.

What is the goal of performing any calculation in a brewing?  The answer to that is question is to give brewers a metric to use in brewing.  IBUs are an analytical laboratory measurement of bitterness.  All of the algorithms for calculating IBUs are approximations of what one would expect bitterness to be using that metric.  AAUs/HBUs give us the same kind of metric just in a much easier to use calculation.  Granted, there is more error, but it is a “good enough” calculation that home brewers used for decades.

AAUs can be tackled multiple ways when formulating a recipe, but the simplest way will be demonstrated. Let’s use Anglo-American Bitter as an example.  That beer was originally formulated using Cluster that had an alpha acid (AA) rating of 6.2% and Cascade that had an alpha rating of 5.6%.  Subsequent brewings of the beer employed Cluster with a 7.3% AA rating.  The cluster that I currently have on hand has an AA rating of 8.0% whereas the Cascade that I have on hand has an AA rating of 7.6%.  There is no way that I can do a one-for-one substitution with these hops and not produce a beer with a different character. I can either sit down and calculate the IBUs added by each addition and then determine the quantity needed to hit those numbers using the new hops, or a I can use AAUs, which I will refer to as a quick-and-dirty method.

AAUs = amount * aa_rating

AAUs₆₀ = 1 x 7.3 = 7.3 AAUs @ 60
AAUs₁₀ = 0.5 x 5.6 = 2.8 AAUs @ 10

new_amount = old_AAUs / new_aa_rating

new_amount₆₀ = 7.3  / 8.0 = 0.91 ounces or 26 grams
new_amount₁₀ = 2.8  / 7.6 = 0.37 ounces or 10.5 grams

If one runs the original AA ratings an quantities and the new AA ratings and quantities through an IBU calculator, one will discover that the values are pretty darn close.  Herein, lies the power of AAUs.  There is no need to power up a computer.  AAU calculations can be performed using pencil and paper.

Remember, any bitterness equation is not going to tell a brewer exactly how bitter a beer is going to taste.  There are lot of variables in that equation, not the least of which is the yeast culture employed in fermentation.  The only way to know if a beer has the correct bitterness level is to brew it a couple of times while tweaking the additions, and then re-brew the experiment that produced the correct level of bitterness to ensure that it was not a fluke.  From that point forward, AAUs will provide a brewer with a fast way to adjust hop additions based on the AA ratings for any given hop.

Using this method and the PPG-based method I outlined earlier, a brewer can scale any given recipe to his/her brewery very quickly.  To scale hops up or down in batch size, one just multiplies the AAU values by the target batch size divided by the original batch size.  While hop utilization improves with volume, this scaling method will hold for most homebreweries.

scaled_AAUs_time-t = recipe_AAUs_time-t *  target_volume / recipe_volume

[system]

@Saccharomyces

…the PPG-based method I outlined earlier…

This works particularly well for all-malt styles but would take slight alteration for say, Trappist style beers, which have a significant portion of sugar.

May have to try this easy method on my next recipe formulation.

[Saccharomyces]

This works particularly well for all-malt styles but would take slight alteration for say, Trappist style beers, which have a significant portion of sugar.

The PPG method holds for Trappist beers or any other beer style that employs sugar.  We have just have to remove the gravity points added by sugar before determining how many gravity points we need to extract from grain when cloning a beer.  I started using this method when I was a 50% extract from grain/50% extract from DME or LME brewer.

Let’s assume that a Trappist recipe acquires 10% of its gravity from sugar.  We want to produce 5 gallons of wort with an O.G. of 1.070 that is 10% crystalline sugar, and our brew house points per pound per gallon (PPG) value is 30.

points_from_sugar = beer_gravity_points * percentage_of_points_that_are_sugar_in_decimal_form

points_from_sugar = 70 * 0.1 = 7

points_from_grain = beer_gravity_points - points_from_sugar

points_from_grain = 70 - 7 = 63

pounds_of_sugar_needed =  points_from_sugar * batch_volume_in_gallons / 45

pounds_of_sugar_needed =  7 * 5 / 45 = 0.78 pounds

pounds_of_grist_needed = points_from_grain / brewhouse_ppg * batch volume_in_gallons

pounds_of_grist_needed = 63 / 30 * 5 = 10.5lbs

It’s that simple.

Working in the opposite direction

batch_gravity_points = ((pounds_of_grist * brewhouse_ppg) + (pounds_of_sugar * 45)) / batch_volume_in_gallons

batch_gravity_points = ((30 * 10.5) + (0.78 * 45)) / 5 = 70

The method shown above works with DME additions as well.  However, we have to reduce the number 45 to 36 when using LME because LME contains water.

[klickitat_jim]

I feel like whats most important is that you can reasonably repeat based on whatever your calculations are. I don’t care if you call it BU, IBU, or whatnot units. If you know that X amount of grain and X amount of hopd makes the beer you want… yippy!