Filter Coffee Machines
What is a ‘pour & serve’ coffee machine and how does it work?
‘Pour & serve’ coffee machines are used to make drip brewed or filtered coffee. They are often in the shape of a ‘C’ with the water being supplied from an integral tank. The water from the tank is ‘instantly’ boiled and fed through a spray head and in to a filterpan containing a paper filter and the coffee grounds. The coffee then falls through a hole in the filterpan and in to a jug below.
The type of coffee produced
These machines make filtered coffee as opposed to espresso which is made by passing a small amount of nearly boiling water through the coffee grounds under pressure. High street coffee shops such as Costa & Starbucks almost always serve espresso. Even if you buy an americano or a latte it is just an espresso with added water or milk.
The differences between home & commercial machines
Commercial machines are produced with higher quality components including, but not always, a stainless steel casing and more powerful ‘instant’ boilers which heat the water up faster. Good makes should be modular in design allowing easy replacement of failed parts such as hot plates & heaters, float switches, control boards etc.
The volume of coffee produced
This is usually expressed in ‘throughput per hour’ and given in litres. However this is only a theoretical maximum not a basis for reality.
Have you ever seen the specifications saying that a machine can make 144 cups per hour? Let’s break that down. If you take a 1.7 litre 12 ‘cup’ jug then a ‘cup’ can be expressed as 142ml. If it takes 5 minutes to make 1 jug of coffee then 60 mins / 5 mins = 12 jugs per hour. 12 jugs per hour x 12 cups per jug = 144 cups per hour.
However, 142 ml is really small for a cup of coffee. Costa use the following sizes:
Primo - 340 ml
Medio - 450 ml
Massimo - 560 ml
And Starbucks use the following sizes:
Short – 240 ml
Tall – 350 ml
Grande – 470 ml
Venti – 770ml
If your machine has a water tank then you will have to be continually filling it up making sure it does not run out of water. The calculation above also does not take in to account the time taken to remove the used filter paper / coffee grounds and put a new one in the filterpan. You cannot do this if hot water is pouring out of the sprayhead. You have also got to serve the coffee you have brewed to free up the jug for a new batch. Unless of course you have 12 jugs spare but then again you may not have 12 hotplates!
In reality if we take a cup to be 240ml and the time taken to brew, serve, fill up & change the paper / coffee to be about 10 minutes per jug you will probably get 40-50 cups per hour from one of these machines at a push. If you need more get two machines or even a bulk brewer.
Types of machines
Pour & Serve coffee machines can be split up in to different types. These include:
Water tank / jug filled – you have to fill them up manually but you can move them and put them anywhere.
Hose connected / auto-fill – The water tank is connected to a supply and is automatically filled.
Thermal carafe types – does not have hotplates to keep the coffee warm. The coffee is brewed straight in to a vacuum jug and can be kept warm with out being ‘stewed’ for several hours.
Airpot types – a variation on the above but a much larger vacuum flask is used. Once full this flask can be moved to a meeting room or serving table. Air pressure dispenses the coffee upon depression of a leaver.