From Shawn
I am frequently asked to brew 30 and 50 cup urns, you know the kind, percolator that takes two hours to finish. How many grounds do I use per 30 and 50 cup pot? I know the grams per cup, but what I want is measures for cups of grounds per filter. Please use a quantity that is palatable to most average people. Not too much not too little. Thanks! It has been a source of contention for too long around here.
Signed,
Shawn
Answer
Brewing coffee with the percolator may not be the preferred method for the best cup, but since this is the brewer you have available let's discuss your question. The time you mention is long generally due to low wattage and a considerable amount of water to heat. Water expands approximately 4% when heated from 65 degrees to 200 degrees F. Adjusting the water volume down by 4% would adjust brew volume to coffee ratio. Assuming the cup or serving size is 5 ounces (30 cups =150 ounces), the brew formula would be approximately 7 ounces (an 8 ounce measuring cup holds approximately 3 ounces of ground coffee) of coarse-ground coffee (increase or decrease for your taste). You may experiment with preheating the water to reduce the coffee to water contact time. You will also want to reduce the temperature as soon as the brew water has cycled through the coffee grounds for approximately six minutes.
Happy Brewing,
Dr. Brew
1 comments: