A short history of acidity in coffee

A short history of acidity in coffee

16 July 2013

Back in the late 1970's around the time Specialty Coffee began as a movement, in and in order to distinguish specialty coffee from big mainstream institutional roasters, acidity stood out as a main distinguishing point of difference. A really ordinary mainstream coffee tasted flat and dull and was ironically very lightly roasted to maximize yield and profitability. A 'special' or specialty coffee was different because it was more lively and had vibrant acidity. From this time onwards acidity was included as a point of difference on Specialty cupping sheets to help define specialty coffee. Interestingly sweetness wasn't valued separately at all on specialty cupping sheets at this time.

This comparison was all primarily based on drip-filter coffee because this was the main way roast and ground coffee was brewed at the time. Espresso was still largely confined to Italian neighborhoods and was not a major focus. One singular contrast that stood out at this time was Peets coffee which eventually evolved into Starbucks signature dark roast coffee and which had very low acidity as a result of its very dark roast.

From there specialty coffee increasingly became defined by how much acidity it had. Eventually debates emerged regarding what was pleasant acidity and what was unbalanced, sour or unpleasant acidity.

The Cup of Excellence (COE) took on this same specialty emphasis so that acidity also defined what was an excellent coffee or a great 'cup of excellence' coffee. The COE cupping sheet was much more sophisticated than the old SCAA cupping sheets and included sweetness among other things, but it still included acidity and the fact remained among cuppers, that if a coffee had a very pronounced acidity it was more highly scored whereas a coffee with a more refined or low acidity wouldn't make it into the ranks of the higher specialty scores, regardless of its other qualities.

When it comes to espresso, which some people may know has become one of my areas of specialization, even though I started out in drip coffee and focused on it for a good decade and a half, acidity has not always been its defining feature.

One of the great turning points for acidity in espresso was at the World Barista championship in Seattle in 2005. I was at the nearby 49th Parallel coffee factory when the winner of the World barista championship that year brought a sample of their winning coffee with them for us to taste. In previous World Championships these guys had used Illy Caffe which they had in fact won with. But this year they used coffee that had been roasted by a North American roaster and the Agtron measurement was about 60 whole-bean and almost 80 on the ground scale. That was very light roasted espresso. With a big spread like this between the whole-bean and ground numbers this was almost below a cupping level roast and certainly accentuated the intrinsic acidity already present in the coffee.

The arresting thing with this coffee was that when made as a cappuccino, it tasted sweetly pleasant because the acidity combined with the milk well but there was very little detectable underlying coffee flavor. I'm not taking anything away from the barista as he's great and a very nice guy. But the fact was that the way the coffees were being evaluated by the judges had shifted in this particular competition and this then cemented the need to emulate the style in order to win the world championship. This was further consolidated by the fact that Denmark went onto win a more barista championships so that when the new kids on the block started coming into the scene from the UK and the USA for instance, this style of high acid espresso was what they had to emulate in order to win; which they duly did and so 'high-acid' espresso became firmly entrenched at this competition level. From there it filtered down (pardon the pun) to the retail level and new entrants into the café market also began buying their coffee from these professionals and so it has proliferated.

Many new operators who have only been in the industry for under say, seven or eight years have had their perception of espresso skewed towards this style, so that in their minds great espresso must have powerful acidity in the same way that Cup of Excellence and specialty coffees do. This espresso style is reinforced by all these previous perceptions in regard to specialty coffee. Personally, I'm not against this as a style of espresso as some people may think, but it really demonstrates just one style of espresso.

Because there are not so many people who have necessarily tasted a different style of espresso, one that doesn't have so much acidity, their immediate instinct is to reject it. That's ok but the kind of maturity the coffee industry needs to aspire to should be more like the wine industry for instance, where somebody isn't saying the only way you must enjoy wine is that it must be a white wine and it must be a cold climate wine that is crisp and acidic.

Fortunately the wine industry which is arguably three times as old as the coffee industry, has had pioneers and visionaries who have been able to successfully produce many different styles of wines, each with its own intrinsic character. But no self respecting wine connoisseur would try and compare a Grange Hermitage for instance, with a Pinot Gris, but neither would either wine style be condemned because it was different to the other.

A part of our Australian espresso heritage has been the extraordinary efforts of our Italian immigrants in particular, who after the Second World War starting producing a classic, rich, smooth, low-acid espresso style coffee. They faithfully produced their style of espresso for decade after decade: the likes of Giancarlo at Grinders in Lygon street Melbourne; Bar Coluzzi in Darlinghurst Sydney, Rio Coffee in Adelaide and many others laid a foundation which spread to the wider community who enjoyed drinking it with milk.

And their style of espresso did work extraordinarily well with milk, because of its wonderful full-body. These guys are the missing link in the development of acidity in espresso. I liked the wonderful rich, smooth low-acid style espresso these pioneers produced because it wasn't as dark roasted as the west-coast USA style espresso and we are all direct beneficiaries of their hard work.

And this is why espresso based culture has now become a part of our Australian social wallpaper. It is expected that you can get a decent espresso based coffee wherever you go and woe betide any cafe operator who doesn't make the grade.