brew

#!/usr/bin/env ruby

$sucrose_points = 386.5

$extract_potential = {
  '2 row' => 0.79,
  'crystal 10L' => 0.75,
  'carapils' => 0.72,
}

wort = 80
gravity = 1.045
ef = 0.70
hours = 1

grains = [
  ['2 row', 92],
  ['crystal 10L', 4],
  ['carapils', 4],
]

puts '=' * 40

grain = 0.0

grains.each do |name, perc|
  gp = (gravity * 1000 - 1000) * wort * perc / 100
  ep = $extract_potential[name]
  weight = gp / (ep * ef * $sucrose_points)
  puts '%s: %0.2f kg (%0.2f lb)' % [name, weight, weight * 2.20462]
  grain += weight
end

l_grain = grain * (1.7) # 1.0 - 1.7
l_evaporation = hours * (5.7)
mash_thickness = 2.78
strike_volume = grain * mash_thickness
mash_volume = strike_volume + 0.67 * grain
runoff_volume = wort / 0.96 + l_evaporation
start_volume = runoff_volume + l_grain

puts '=' * 40
puts 'grains = %0.0f kg (%0.2f lb)' % [grain, grain * 2.20462]
puts 'strike_volume = %0.0f L' % strike_volume
puts 'mash_volume = %0.0f L' % mash_volume
puts 'sparge_volume = %0.0f L' % (start_volume - strike_volume)
puts 'runoff_volume = %0.0f L' % runoff_volume
puts 'start_volume = %0.0f L' % start_volume
puts '=' * 40