Creating your own beer recipe

Step 1: start from a style and its figures

Even for a beer you want to be original, a style gives bounds that guarantee a balanced beer: original and final gravity, bitterness, colour, alcohol. The list of styles gives them for 103 styles. For an American pale ale (18B): gravity 1.045 to 1.060, final 1.010 to 1.015, 30 to 50 IBU, 10 to 20 EBC, 4.5 to 6.2 % alcohol. You set a target within the range: 1.052, 38 IBU, 12 EBC, 5.1 %.

Step 2: volume and efficiency

The volume is what arrives in the fermenter, not the kettle's. The efficiency is your set-up's, measured (see brewhouse efficiency), or 72 % failing that. The whole recipe depends on it: the same list of malts gives 1.052 at 72 % and 1.047 at 65 %.

Step 3: the malts and the gravity

A simple principle: a base malt for 80 to 95 % of the grist, one or two speciality malts for the rest. The usual proportions:

The gravity is calculated with the estimated original gravity tool: points = Σ(kg × malt yield × 384 × efficiency) / litres. A malt's yield is on its sheet (0.78 to 0.82 for base malts, 0.72 to 0.76 for caramels). For the example, at 72 % and 20 litres:

• 4.5 kg pale ale malt (yield 0.80): 4.5 × 0.80 × 384 × 0.72 / 20 = 49.8 points
• 0.3 kg caramel malt 40 EBC (yield 0.74): 0.3 × 0.74 × 384 × 0.72 / 20 = 3.1 points
• Total 52.9 points, original gravity 1.053

A little above the 1.052 target: that is fine. If the target were far off, you adjust the amount of base malt, never the speciality malt, whose share defines the character.

Step 4: the colour

The EBC colour tool applies the Morey formula to each malt's colour and quantity. With 4.5 kg of pale ale at 6 EBC and 0.3 kg of caramel at 40 EBC for 20 litres, you get about 12 EBC: a golden to light amber beer, on target. To darken without sweetening, replace part of the caramel with a roasted malt; to lighten, take pilsner as the base.

Step 5: the hops and the balance

Bitterness alone says nothing: 38 IBU in a beer at 1.052 is a properly bitter pale ale, the same 38 IBU in a 1.080 make a malty beer. The BU:GU ratio, IBU divided by gravity points (the BU:GU ratio tool), measures the balance:

Target of the example: 38 IBU for 53 points, BU:GU = 0.72, a frankly hoppy pale ale. The classic split is a bittering addition at the start of the boil (60 minutes) making 50 to 70 % of the IBU, then aroma additions in the last 15 minutes. With Cascade at 6 % alpha acids in pellets, 20 litres at the end of the boil, boil gravity 1.052, the Tinseth formula (IBU calculator tool) gives:

The alpha acid content changes with every harvest: redo the calculation with that of the packet you bought. A hop at 8 % instead of 6 needs 25 % less for the same IBU. The boil schedule tool gives the time of each addition.

Step 6: the yeast, the final gravity and the alcohol

The yeast decides the final gravity by its attenuation (the share of sugars it consumes, 70 to 85 % depending on the strain) and the character by its esters. For an American pale ale, a neutral American yeast at 75 to 80 % attenuation. The estimated final gravity tool gives: 1.053 − 0.053 × 0.76 = 1.013. The alcohol, by the hydrometer tool: (1.053 − 1.013) × 131.25 = 5.2 % ABV. On target. The amount of yeast is calculated with the pitching rate: one 11 g sachet is enough here; above 1.060, two or a starter.

The resulting recipe

• American pale ale, 20 litres, efficiency 72 %
• 4.5 kg pale ale malt, 0.3 kg caramel 40 EBC
• Mash at 66 °C, 60 minutes, about 14 litres of water, then sparge for 26 litres before the boil (water volumes tool)
• Boil 60 minutes; Cascade 30 g at 60, 15 and 5 minutes
• Neutral American yeast, 18-20 °C, 10 to 14 days
• Dry hop Cascade 60 g, 4 days (see Getting your dry hop right)
• Estimated result: 1.053 / 1.013, 38 IBU, 12 EBC, 5.2 %, BU:GU 0.72
• Priming for 2.4 volumes: about 125 g of dextrose (priming tool)

Next: brew, measure, correct

A recipe only becomes good at the second batch. Note the gravity actually obtained (if it is 1.048 instead of 1.053, the efficiency was too optimistic, not the recipe), taste with the sheet from the tasting article, and change only one thing at a time: the dose of a hop, the share of caramel, the mash temperature. The variants of one recipe stay within the same style, which makes them comparable.

Changing scale or volume

Going from 20 to 25 litres or adapting a recipe found for 19 litres (5 gallons): the scaling tool multiplies the grains by the ratio of volumes corrected by the ratio of efficiencies, and the hops by the ratio of volumes alone.