Microbiology of Beer, Bread and Cheese – Spring 2013
Laboratory Worksheet 1: Chemical Analysis of Beer
Instructions: You should do this worksheet as a team (1 team per table). Feel free to double-check your answers with those of the other teams. You will be responsible for being able to do these calculations on the next test, so make sure you understand them, even if your fingers are not pressing the calculator buttons. Please show your work for all calculations. These worksheets are due today.
Names______
______
______
- Calculate the Alcohol By Volume for both beers (ABV = ml alcohol/ml beer)
ABV = (OG - FG) / 0.75
Brewpub yeast beer:
Kit yeast beer:
- Calculate the Plato Scale for both beers (°P) 1° Plato is equivalent to 1% sucrose (1 g sucrose/100 g beer).
°P = (-463.37) + (668.72 × SG) - (205.35 × SG2)
Brewpub yeast beer:
Kit yeast beer:
3. Calculate the Real Extract for both beers
RE = (0.1808 × °Pi) + (0.8192 × °Pf)
Brewpub yeast beer:
Kit yeast beer:
4. Calculate the Apparent and Real Attenuation values for both beers
AA = 1 - [°Pf / °Pi]
Brewpub yeast beer:
Kit yeast beer:
RA = 1 - [RE / °Pi]
Brewpub yeast beer:
Kit yeast beer:
5. How many Calories does 12 oz. of each beer have?
cal per 12 oz beer = [(6.9 × ABV) + 4.0 × (RE - 0.1)] × FG × 3.55
Brewpub yeast beer:
Kit yeast beer:
Test 2: Beer Color
1. Measuring Beer Color:
EBC
The European Brewing Convention (EBC) has created a method to quantify beer color, based on the beer’s absorbance at 430nm (A430), using a 1cm path length. For EBC values, the absorbance is then multiplied by 25.
Brewpub yeast beer:
Kit yeast beer:
Degrees Loviband (°L)
The American Society of Brewing Chemists quantifies beer color using the Standard Reference Method (SRM).
SRM = EBC/1.97
Brewpub yeast beer:
Kit yeast beer:
Test 3. Beer Bitterness
Bitterness Units (BU)= Abs @275x50
Brewpub yeast beer:
Kit yeast beer: