Union Revelation review: a dark espresso kilo built for milk

Revelation was designed for one job: to taste of something through a lot of milk. Union's founders say so in as many words, and more than a decade of home-barista opinion agrees with them. In a latte, a flat white or a cappuccino from a bean-to-cup, this is a well-made dark blend at 48p a cup, about a quarter under the whole bean median. As a straight espresso it divides people. If you like your coffee light and bright, it is the wrong bag, whatever it costs.

Live prices, sizes and retailers for this coffee sit on its product page. This review is the analysis alongside it. See prices →

Who Revelation is for

Start with how you drink your coffee. Union's founders first built this blend in 1994, as TM Espresso, before Union existed, and they describe the brief plainly: sweet, smooth on the palate, 'but still bold enough to come through that milk'. The home baristas who have written about it since say much the same. Milk drinkers praise it. People who drink espresso black and like it lighter call it too dark. If you are in the first group and get through coffee quickly, this is a strong kilo for the money. If you are in the second, no price makes it right.

What the label says

Union publish more about this coffee than most roasters bother to. It is a dark roast of speciality arabica from family farms in Costa Rica, Guatemala, Nicaragua, Rwanda and Burundi, with washed, pulped and honey-processed coffees in the mix. The published notes are treacle, cinnamon and dark chocolate with a caramel finish, and Union give it 84.5 on the Speciality Coffee Association's quality scale, where anything over 80 counts as speciality. The Amazon listing is far thinner. It says only that the beans are best brewed as espresso or filter.

Two details on that list deserve a second look. The components change through the year, which Union say is how they keep the taste steady, though the blend stays anchored by Costa Rica and Guatemala. And the roast is lighter than it used to be. Union's own history of the blend says it 'has gotten lighter in roast over the years' as people moved to smaller, less milky drinks. Bear that in mind when you read the older opinions below.

Espresso, milk or filter?

Milk first, because that is where the accounts agree. In a 2013 Coffee Forums UK thread, one owner called it 'probably the best i've tried in terms of a proper dark roast' and said it 'cuts through milk really well'; another, who drinks only espresso, described 'a rich fat mouthful of dark chocolate' with great crema. The 100 Espressos blog pulled it on a Sage Bambino Plus with a Smart Grinder Pro in October 2022 and picked out heavy dark chocolate and treacle with 'very noticeable cinnamon', a note it thought worked especially well in cappuccinos and flat whites.

Straight espresso is where opinion splits. In that same 2013 thread two regulars called it far too dark for them, and a third found it 'slightly more tricky to pull correctly' than Union's Foundation blend. In 2024 the dmc...errrmmmm coffee reviews channel on YouTube judged it pleasant and good quality but not distinctive enough for its supermarket price, and pointed to Taylors of Harrogate for more character at half the money. Keep the dates in mind. Most of the too-dark verdicts date from 2013, and Union's 2021 account of the blend says the roast has got lighter over the years.

Filter is the gap in the record. Union list it for cafetière, pour-over, AeroPress and drip, with dark chocolate and gentle cherry as the filter notes, but nobody independent appears to have written about brewing it that way. If filter is all you make, you are taking Union's word for it.

Grind finer than you expect. Union's espresso guide asks for 17 to 19g in, 28 to 36g out, in 22 to 30 seconds, from a grind 'like powder'. The 100 Espressos write-up found a single step on the grinder was the difference between a good shot and 'a sour mess', so adjust in small steps.

In a bean-to-cup machine

Union name the bean-to-cup outright, alongside a café-style espresso machine, as the way to brew this coffee as espresso. It suits the way those machines get used. Most of what a bean-to-cup makes has milk in it, and a blend designed to punch through a big café latte has plenty in hand for a 200ml cappuccino.

The usual worry with a dark roast in an automatic machine is oil, which can stick in the hopper and gum up the built-in grinder. One 2013 forum post was 'surprised how dark and oily the Revelation beans are', but Union say the roast has got lighter since the early days, and nobody in the later threads raises it. Look at the beans when the bag arrives. Dry, matte beans are fine. A visible sheen means keep the hopper topped up only a day at a time and clean the grinder more often.

Expect to set the grinder near its fine end. Bean-to-cup grinders have fewer steps than a standalone one, and with a coffee that can swing on one step, give it a few test drinks before you decide you dislike it.

How long a kilo stays good

Union are specific about freshness. For espresso they suggest resting beans for five to ten days after roasting, and they say coffee is at its best until about four weeks from roasting. At two cups a day on our 18g dose, a kilo lasts about 28 days. Add the resting days and the time in transit, and the last part of the bag falls outside Union's own window before you reach it.

The Amazon listing gives no roast date and no promise about how old the bag will be on arrival. Union's supermarket bags do carry a roast date, and one 2020 forum post describes Union coffees on the same shelf ranging from a few weeks to four months past roasting. Check the date as soon as the kilo lands.

The fix is the one Union suggest themselves. Freeze half the kilo in a sealed bag, keep the rest in an airtight tin in a cool cupboard, and never put it in the fridge. Union say you can grind straight from frozen. If you drink one cup a day, a kilo is eight weeks of coffee, and the 500g bag is the better buy even at a higher price per cup.

What it costs, and how to pay less

48p a cup is about a quarter below the 63p median for whole bean coffee on this site, on the same 18g dose. For a speciality blend that publishes its origins and its quality score, that is a keen price.

The 500g bag of the same coffee works out at 58p a cup at the prices we track, so the kilo saves about 10p a cup. That gap moves. The kilo's Amazon price shifts by a few pounds, and when it rises the half-kilo comes within a couple of pence a cup of it, at which point the smaller, fresher bag is the better deal. Compare the two per cup on the day you order, and use Subscribe & Save if the listing offers it.

One oddity on the listing pages. Union's Daily Roast Espresso, sold on Amazon in 500g bags at 56p a cup, is described in almost the same words as Revelation: 'our most popular espresso coffee bean', 'a bold one with hints of chocolate and treacle'. Union do not say the two are the same coffee, and a shared description is not proof that they are. It is still worth a look if the Revelation half-kilo is out of stock or dearer that day.

Who should skip it, and what to buy instead

Skip it if you like light roasts; Union call it bold and dark, and the regulars who dislike it all say the same thing, too dark. Skip the kilo if it would take you two months to finish. And think twice if you only brew filter, not because it is likely to be bad but because nothing independent tells you it will be good.

• Want a dark roast for less? Taylors Hot Lava Java is an extra-dark, smoky blend at 40p a cup. Taylors say it contains robusta, added for caffeine; Union say all their coffee is 100% arabica.
• Want more punch in milk? Rave's The Italian Job Nº 2 is roasted darker than Rave's usual style with 'a splash of high quality Robusta', and Rave say it punches through milk. It costs 59p a cup.
• Find Revelation too heavy? Pact House Coffee is a softer Brazil and Colombia blend sold on milk chocolate and toffee, at 53p a cup.