When you need a fast coffee pot that brews a large amount at one time, you need the Grindmaster Columbia Series Twin Shuttle Coffee Brewer (P400E). This handy machine lets you brew up to 1.5 gallons of coffee in one easy place and features two shuttles that promise the freshest coffee possible for hours at a time. The pots are also easy to transport so you can make refills in your restaurant, hotel or cafeteria with ease. The Grindmaster - P400E - Columbia Series Twin Shuttle Coffee Brewer also has a hot water faucet that can be used to make tea and cocoa without having to have a separate machine.
According to the manual, Grindmaster suggests the following: Your coffee supplier can help you select the right amount of coffee and grind. Coffee brewing experts recommend between 6.5 and 8 ounces of coffee per gallon of water for most applications. A full shuttle is 1.4 gallons and a full airpot is 0.80 gallon. With that said, if you don't have a brewing expert to rely on, I'd recommend doing a search on 'commercial coffee grind' to learn more about what others may suggest. What I can share with you here is that you want to know the difference between brewing time and water contact time, which is determined by the size of the grind and the bed depth - how much coffee you have in the filter, which is typically 1-2 inches. These different factors help determine the strength, flavor, and aroma of the coffee. Experimenting may be key to finding what you prefer to serve.
The Columbia Series Twin Shuttle Coffee Brewer uses a 13" x 5" coffee filter.