Reference guide · Updated on 2026-08-09 · Café en Casa Team

Capsule machines: systems, cost per cup and alternatives

Q: Why is my espresso watery and sour?

Almost always because the extraction is too fast: if it runs through in under 20 seconds, grind finer or increase the dose. Also check that the coffee is freshly roasted and that you are purging the group head before extracting.

Q: What water should I use in the machine?

Weakly mineralised water, with dry residue below 100 mg/l, or filtered tap water. Distilled will not do: with no minerals the coffee tastes flat and some level sensors cannot detect it. Water is 98% of the cup, so changing it makes more difference than moving up a machine range.

Q: How do you store coffee beans?

In an airtight opaque container, at room temperature and away from kitchen steam. No fridge and no freezer for daily use: the beans absorb moisture and smells every time you take them out and put them back. Buy 250-500 g bags and use them within three or four weeks.

Q: What is the difference between espresso, lungo and ristretto?

It is the same dose of coffee with a different amount of water. A ristretto is around 18 g for 25 ml and comes out dense and sweet; a double espresso, 18 g for 36 ml; a lungo goes past 60 ml and drags in more bitterness because it keeps extracting when there is nothing good left. If you want a long, mild coffee, go for an americano instead: espresso with hot water added.

Q: What budget do I need for a nespresso machine?

It depends on your use: there are valid options in the entry range and advanced models that only pay off if you are going to make the most of their features. Go through the criteria in this guide, define your real use and compare the current price on Amazon before deciding.

We compare the capsule systems on real cost per cup, quality in the cup and compatibility, refillable capsules included.

Capsule machines: systems, cost per cup and alternatives

Capsules or beans: the real cost per cup

Here the numbers are clear. A closed-system capsule costs between 0,30 and 0,45 €; own-brand compatibles come down to 0,15-0,22 € but with uneven quality. A kilo of freshly roasted whole beans costs 15-25 € and yields around 55 double doses of 18 g, that is 0,10-0,15 € per cup. At two coffees a day, the annual difference is around 150-200 €: a 400 € bean-to-cup machine pays for itself in a little over two years against capsules. Capsules win on convenience, zero cleaning and zero learning curve; whole beans win on cost, freshness and quality ceiling.

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Bean-to-cup: what justifies the jump in price

Between a 300 € bean-to-cup machine and a 800 € one there are four real differences: the grinder (number of steps and whether it is steel or ceramic), the temperature and ratio control per drink, the milk circuit (removable and washable versus fixed) and the ease of maintenance (removable brew group or not). What does not justify the jump: big screens, the number of pre-programmed recipes and app connectivity, which almost nobody uses after the first month. If you make one or two milk drinks a day, the sweet spot is between 400 and 600 €.

The 9 bars of pressure that really matter

Almost every entry-level machine advertises 15 or 20 bar, and it is a marketing figure: that number is the maximum pressure of the vibration pump, not what reaches the coffee. A correct espresso is extracted at 9 bars at the group head, and above 11-12 the extraction turns bitter because it drags out compounds that should stay behind. A 15 bar machine with a properly calibrated OPV valve makes better coffee than an unregulated 20 bar one. When comparing, ignore the bar figure and look at whether the portafilter is pressurised or not, and at temperature stability.

Water hardness and descaling: what kills coffee machines

The number one cause of breakdowns is limescale, not use. Across much of the Mediterranean coast and central Spain the water exceeds 25-30 °fH, and at that hardness a machine without a filter needs descaling every 1-2 months; with soft water (<15 °fH) you can stretch it to 3-4 months. Use filtered water or bottled water with weak mineralisation (dry residue below 100 mg/l), set the hardness in the menu if the machine allows it, and do not ignore the descaling warning: once the heating element scales up, the water no longer reaches temperature and the coffee tastes thin long before the machine actually fails.

Mistakes that ruin coffee (and it is not the machine)

Five mistakes explain most bad coffee at home: using months-old ground coffee kept in the opened bag; very hard water or tap water with chlorine; do not warming the cup, which drops the temperature of the drink by 8 to 10 °C at a stroke; not purging the group head before extracting; and tamping with uneven pressure, which creates channels where the water escapes without extracting. None of them cost money to fix. Before changing machine, correct these five: in most cases the problem was never the appliance.

Steam wand: classic lance or automatic system

If you like cappuccino or flat white, this decides your purchase. The classic steam wand forces you to learn to texture the milk (create the vortex, not make bubbles) but gives café-quality microfoam and works with plant milks. The automatic systems systems such as LatteGo or a cappuccinatore handle the milk on their own, with no technique needed: the result is decent and very repeatable, but foamier and less creamy. One practical detail: LatteGo comes apart into two washable pieces, whereas milk circuits with internal tubing demand cleaning cycles and end up smelling if you neglect them.

All Capsule Coffee Machine articles (36)

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Frequently asked questions about nespresso machines

Why is my espresso watery and sour?

Almost always because the extraction is too fast: if it runs through in under 20 seconds, grind finer or increase the dose. Also check that the coffee is freshly roasted and that you are purging the group head before extracting.

What water should I use in the machine?

Weakly mineralised water, with dry residue below 100 mg/l, or filtered tap water. Distilled will not do: with no minerals the coffee tastes flat and some level sensors cannot detect it. Water is 98% of the cup, so changing it makes more difference than moving up a machine range.

How do you store coffee beans?

In an airtight opaque container, at room temperature and away from kitchen steam. No fridge and no freezer for daily use: the beans absorb moisture and smells every time you take them out and put them back. Buy 250-500 g bags and use them within three or four weeks.

What is the difference between espresso, lungo and ristretto?

It is the same dose of coffee with a different amount of water. A ristretto is around 18 g for 25 ml and comes out dense and sweet; a double espresso, 18 g for 36 ml; a lungo goes past 60 ml and drags in more bitterness because it keeps extracting when there is nothing good left. If you want a long, mild coffee, go for an americano instead: espresso with hot water added.

What budget do I need for a nespresso machine?

It depends on your use: there are valid options in the entry range and advanced models that only pay off if you are going to make the most of their features. Go through the criteria in this guide, define your real use and compare the current price on Amazon before deciding.

Other guides from Mejor Café en Casa

Espresso machines Bean-to-cup machines Moka pot, AeroPress, V60 and Chemex Coffee grinders Whole beans Drip and office coffee machines Coffee machine maintenance

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