Best Coffee Beans for a Filter Coffee Machine: A Caffé Prima Guide
The best coffee beans for a filter coffee machine are smooth, sweet-leaning Arabica beans at a medium roast or lighter. At Caffé Prima, that means our 100% Colombian and our Brazilian 100% Arabica. This guide covers which of our beans to choose, how much coffee to use, what grind a filter machine needs, and how to stop the machine itself from spoiling the cup.
Which Caffé Prima Beans Work Best in a Filter Coffee Machine?
A filter machine pours hot water over the grounds with no pressure, so it rewards beans that taste good without espresso-style extraction. Two beans in our range are rated excellent for filter and two more are rated good.
100% Colombian: the top pick
Caffé Prima 100% Colombian is a mountain-grown single origin at a medium roast. It tastes of caramel, hazelnut and almond, with balanced acidity and a full body that holds up across a whole jug. It is also rated excellent for pour over, so the same bag works if you add a second brewing method later.
Brazilian 100% Arabica: the smooth everyday pick
Caffé Prima Brazilian 100% Arabica is our lightest roast. The cup is smooth and mild, with almond and chocolate notes and gentle acidity. It suits anyone who finds darker roasts too intense for a first coffee of the day, and filter and pour over are the brewing methods that suit it best.
Roma: the brighter option
Caffé Prima Roma combines beans from Brazil, Honduras and Vietnam at a medium roast. It has citrus and nutty notes and a brighter finish than our darker beans. It is rated good for filter, and it is the one to choose if you want a cup with more lift than the Brazilian.
Decaffeinated Brazilian Arabica: the evening jug
Caffé Prima Decaffeinated Brazilian Arabica is decaffeinated using the CO2 process, a chemical-free method that keeps the flavour of the bean. The cup tastes of milk chocolate with a silky body. It is rated good for filter and uses the same dose and grind as the other beans, so a second jug for the evening needs no change to your routine. Our decaf coffee guide explains how the decaffeination methods differ.
Bolder beans: possible, not ideal
Continental Blend, Espresso Blend and Italian Mahogany were roasted with espresso in mind. They work in a filter machine and give a heavier, lower-acidity cup, but they are rated possible rather than excellent. Choose one of them if you like your filter coffee dark and strong. For a side-by-side look at the whole range across every brewing method, see our coffee bean comparison.
How Much Coffee Should You Use in a Filter Machine?
The Specialty Coffee Association tests certified home brewers at a ratio of 55 g of coffee per 1.000 kg of water. A kilogram of water is about a litre, so the working rule is 55 g of coffee per litre. Weigh the coffee on kitchen scales, because scoop sizes vary with the grind and the roast.
| Water | Coffee |
|---|---|
| 250 ml (one mug) | 14 g |
| 500 ml (two mugs) | 28 g |
| 1 litre | 55 g |
| 1.25 litres (a 10-cup jug) | 69 g |
At 14 g a mug, a 1kg bag makes about 70 mugs. Add or remove a gram or two per mug to suit your taste once you know how the machine behaves.
What Grind Size Does a Filter Machine Need?
A filter machine needs a medium grind. The SCA standard sets a reference grind that depends on the shape of the basket. For a conical basket, at least 68% of the particles should fall between 425 and 850 micrometres, which is roughly 0.4 to 0.85 mm. For a flat-bottom basket, at least 65% should fall between 589 and 1168 micrometres, roughly 0.6 to 1.2 mm. A flat-bottom basket therefore wants a slightly coarser grind than a cone.
Taste tells you which way to adjust. The SCA's research for its brewing chart, run on a commercial batch brewer, found that bitterness increases as extraction increases, while sourness decreases. A finer grind raises extraction, so bitter coffee needs a coarser grind and sharp, thin coffee needs a finer one. Change the grinder one step at a time.
Grind just before you brew. Grinding exposes far more of the coffee to air, so ground coffee loses its flavour much faster than whole beans. Our guide to storing coffee beans covers how to keep the rest of the bag at its best.
How Hot Should the Water Be in a Filter Machine?
The SCA standard requires the brew water to reach 90 to 96°C by the time a third of the water has been sprayed onto the coffee, and to stay in that range for the rest of the cycle. Machines differ in how well they manage this, so check the brew temperature in your manual. Some machines let you set it yourself: the Sage Precision Brewer Thermal has a My Brew mode that lets you customise the bloom time, brew temperature and flow rate. If your coffee tastes sour and thin, a machine that runs cool is one possible cause, alongside a grind that is too coarse.
The holding temperature matters as much as the brew. The same SCA standard asks heated carafes to keep coffee at 80 to 85°C for the first 30 minutes. A thermal carafe keeps the jug hot without a heating plate underneath it, so the coffee does not keep cooking after the brew has finished.
How Fresh Should Beans Be for a Filter Machine?
Every roast level in our range has finished its fast degassing phase by the time an order arrives, so the beans can go straight into the grinder. Caffé Prima typically delivers within four weeks of roasting, which leaves several more weeks of good flavour ahead. Once the bag is open, the job is to keep it sealed with its one-way valve and to grind only what you need for each brew.
GOV.UK explains that best before dates relate to quality rather than safety, and that food is usually safe to eat after the date but may not be of the same quality. The same logic applies to a bag of beans: an old bag tastes flat, but it is not a safety risk. Our guide to coffee freshness explains the science behind resting and staling.
Does Water Hardness Matter for a Filter Machine?
Yes, because hard water leaves limescale inside the machine. The Drinking Water Inspectorate says hard water causes scaling in hot water systems, kettles, electric irons and domestic appliances, and a filter machine heats water in the same way. It classes water as soft up to 100 mg/l of calcium carbonate, hard from 200 to 300 mg/l and very hard above 300 mg/l. Hardness varies with local geology, and the regional map only shows typical figures, so ask your water company for an accurate measurement for your address. Descale the machine as its manufacturer instructs. Our water-smart guide covers how water affects the cup.
How Do All the Caffé Prima Beans Compare for Filter Brewing?
| Caffé Prima bean | Roast | Filter machine suitability |
|---|---|---|
| 100% Colombian | Medium | Excellent. The top pick for balance and body. |
| Brazilian 100% Arabica | Light | Excellent. Smooth and mild. |
| Roma | Medium | Good. Brighter, with citrus notes. |
| Decaffeinated Brazilian Arabica | Medium to dark | Good. The decaf option for filter. |
| Continental Blend | Medium-dark | Possible. Bolder, lower acidity. |
| Espresso Blend | Medium | Possible. Made for espresso. |
| Italian Mahogany | Dark | Possible. Heavy, very low acidity. |
| Decaffeinated Espresso | Dark | Possible. Bold decaf. |
Common Questions About Beans for Filter Machines
What is the best coffee bean for a filter coffee machine?
Caffé Prima 100% Colombian is the best all-round choice. Its medium roast, balanced acidity and caramel and hazelnut notes suit the gentle extraction of a drip machine. The Brazilian 100% Arabica is the better choice if you prefer a lighter, milder cup.
Can you use espresso beans in a filter machine?
Yes. Espresso Blend, Continental Blend and Italian Mahogany all work, but they are rated possible because they were roasted for espresso. Expect a bolder cup with lower acidity than the Colombian or Brazilian gives.
Can you use decaf in a filter machine?
Yes. Decaffeinated Brazilian Arabica is rated good for filter and uses the same dose and grind as regular beans. The CO2 process keeps its milk chocolate flavour and silky body. Decaf still contains a trace of caffeine, so it is not completely caffeine-free.
How many mugs does a 1kg bag make in a filter machine?
About 70 mugs at 14 g of coffee per 250 ml mug. A stronger brew uses more coffee per mug and gives fewer mugs from the bag.
Where Can You Order Beans for a Filter Machine?
Caffé Prima beans are roasted low and slow in small batches in the UK, with a maximum of six weeks from roast to delivery. Orders over £45 ship free next day, and there is no minimum order. See the full Caffé Prima coffee bean range for home buyers, or order 6kg cases from the wholesale collection for offices and cafés that run a filter machine all day.
