What to Expect When You Are Extracting Beer and Loafing NHC 2004 Las Vegas, NV
What is Extraction? • Simply: The amount of wort you get from the grain you mash and lauter, expressed as a number of some sort. • ex. 29 Points/pound/gallon • More completely: The amount of soluble extract (wort), that is extracted from the mash and lauter, usually expressed as a percentage of the total soluble extract that was obtained from a laboratory mash. • i.e. “extraction efficiency”
Congress Mash • Named for the standardized process instituted by the European Brewing Congress (EBC) in 1975. • A standard weight of finely ground malt is multi-infusion mashed over a period of nearly 2 hours. • The mash is filtered thru a paper filter for a period of 1 hour and the specific gravity is measured. The % Extract, Fine Grind, As-Is is calculated from the ASBC Table for Extract Determination in Malt.
Extract: Fine Grind • The Congress mash uses finely ground malt to determine the % Extract, Fine Grind, As-Is • The fine grind allows the enzymes more access to the starches to assure full conversion. • The % moisture is calculated by drying a portion of the malt in a forced air oven at 103-104°C for 3 hours, and the % Extract Dry-Basis is determined. • % Extract, Fine Grind, Dry-Basis is the standard value for comparing all malts.
Extract: Coarse Grind • % Extract Coarse Grind is just what it says - a coarser grind than Fine Grind, but one that is probably finer than most homebrewers use. • Coarse Grind is more representative of a typical mash and sparge could achieve. • % Extract, CG, As-Is/Dry-Basis are usually only measured for primary malts, not for specialty malts.
Fine/Coarse Difference • F/C Difference is the percentage difference between the % Extract for Fine and Coarse Grinds. (As-Is or Dry Basis – same difference) • If the F/C difference is small (1%) then the malt is highly modified, i.e., the starches are readily convertible in the coarse ground state. • A less modified malt would have a larger F/C.
Soluble/Total Nitrogen Ratio • Also known as the Kohlbach Index • The ratio indicates the degree that the endosperm (carbohydrate/protein matrix) has been enzymatically unlocked (modified). • To generalize*: an S/T ratio of • 30–36 is less-modified (Decoction)** • 36-42 is well-modified (Single, Multi-Infusion) • 42–48 is highly-modified (Single Infusion) *Opinions vary **Protein Rest-able
Hot Water Extract (HWE) • This is the British measure of potential extract, measured in Liter•Degrees/Kilogram • Single Infusion Mash vs. Congress Mash • It is equivalent to Points/Pound/Gallon • i.e., Gallon•Degrees/Pound (PGP) • Conversion factor is HWE = PPG x 8.345 • 300 HWE ≈ 36 PPG, 250 ≈ 30 PPG, 230 ≈ 27.5
Extract Efficiency and Typical Yield • A malt with 80% FGDB will contribute 80% of its weight as soluble extract. The other 20% is cellulose and insoluble proteins. • Sucrose (table sugar) is the reference standard, and yields 100% of its weight as soluble extract, raising the gravity by 46 PPG (1.046) when dissolved to form 1 gallon of solution. • 80% FGDB x 46 = 37 PPG • If 4% moisture => 76.8% FGAI x 46 = 35 PPG • If F/C = 2%, => 74.8% CGAI x 46 = 34 PPG
Calculating Your Efficiency • 80% FGDB x 46 = 37 PPG • If 4% moisture => 76.8% FGAI x 46 = 35 PPG • If F/C = 2%, => 74.8% CGAI x 46 = 34 PPG • Efficiency is usually quoted with respect to %Extract FGDB. (ex. 37 PPG) • If you get 7 gallons of 1.038 from 9.5 lbs grain after mashing & lautering (ex. 7•38/9.5=28 PPG), then 28/37 = 76% Efficiency
Lautering Efficiency • Brewing Efficiency is the difference between what you get, and what the laboratory gets. • Efficiency can be described as two parts: • Mash Efficiency: How well you Converted • Lautering Efficiency: How well you Separated • You may have had great conversion, but if you sparge with 5 gallons in 10 minutes thru a single pipe, your efficiency (and yield) will be low.
Continuous Sparging • Continuous or Fly Sparging is a newer method (last 300 years or so) than batch sparging. • It relies on steady state, low velocity flow to achieve the maximum extract efficiency. • 75–85% • Works fairly well with a single pipe. • Works better with a multi-pipe manifold. • Works best with a false bottom.
Batch Sparging Lautering • This is an older method, where the mash is drained, re-infused, rested for a short time, and drained again. • Very simple to do. • Efficiency is usually good. 70–80% • Single Pipe works as good as a False Bottom!
Batch Sparge Tips • Plan to get half of your boiling volume from each runnings. • For 9 lbs of grain, yielding a 6 gallon boil of 1.041, you should try to get two 3 gallon batches of wort. • Retained wort is about .5 quart/lb, so about 1 gallon will be retained, and your mash ratio will be a little less than 2 qts/lb. (see How To Brew for details) • Second runnings are typically >1.012, which is above <1.008 zone where pH rises rapidly.
No-Sparge Lautering • No-sparge brewing is probably either the oldest or the newest method – Mash & Drain • The result is a beer produced entirely from the first runnings. • Richer and smoother, due to less tannins and silicates being extracted from the husks. • Uses 20-25% more grain than Continuous • Uses 10-15% more grain than Batch • Efficiency is not bad, 60–70% • Single Pipe works as well as a False Bottom!
What Can You Expect? • You can now read a Malt Analysis Sheet. • % Extract, Fine Grind, Dry Basis, Wind from the Zoo, on Tuesday after feeding time… • You now understand what Modification is and what it means to your brewing method! • You now know how wort flows thru a grainbed. • Complex, symmetric designs only matter when you are continuously sparging. • You can batch sparge, and not worry about oversparging, with only a small loss in potential efficiency.