It’s clear that the two main contributors to emissions from production result from fertiliser use on the farm and fermentation from wet processing at the mill. Yet the studies that we’ve discussed vary widely in their estimates, due partly to the different conditions in each country but also to differences in …

For pour-over methods like V60, Barista Hustle has long advocated using very hot water for brewing coffee — just off the boil, or at around 98°C for anyone using a temperature-controlled kettle. However, in our new course about …

Coffee grows natively under forest trees, and it is well adapted to growing under shade. ‘Agroforestry’ refers to a system of cultivation in which coffee is grown amidst forest trees. These may be native forest trees or they may be deliberately planted, whether for shade and firewood, to fix nitrogen in the soil …

Establishing the coffee plantations in Brazil that made it the world’s biggest supplier of coffee came at a huge environmental cost. Huge swaths of tropical rainforest were felled and burned to clear the land for coffee seedlings (M Pendergrast, 2010). The fertile soil, enriched with humus …

In case you didn’t know, for most of our blog posts we ask readers in our Facebook group to pick questions for us to answer. This week, you voted for this question: ‘What happens if you take coffee grinds and put them in the oven at 70° C to disperse roasting gases, and then make an espresso?’

The major contribution to the carbon produced at the wet mill is the methane and other greenhouse gases released in the wastewater. In Kenya, where traditional washed processing uses large amounts of water for fermentation …

Hardness is a measure of the amount of certain minerals in water. The amount and proportion of minerals in your brewing water can have a dramatic effect on the flavour of your coffee, as well as affect how likely your espresso machine is to get scaled up, so it’s worth trying to understand …

At the farm, the major input, from the point of view of the carbon footprint, is the fertiliser. According to Killian et al.’s study in Costa Rica, it accounts for around 94% of the carbon footprint of this stage of coffee production. By contrast, fossil fuel …

The Rao Spin is a technique in which the barista swirls the filter cone during brewing, to make the slurry spin. It’s named for Scott Rao, who popularised — but did not invent — the technique.¹ It’s thought to increase extraction, reduce channeling and make brews more consistent. But how does it have this effect?

Cascara has been regularly hailed as the next big thing in coffee. Once a rare novelty in speciality coffee, in recent years everyone from Starbucks to Stumptown has jumped on the trend for cascara-infused drinks. In 2018, demand for cascara became so high that the price far outstripped that of coffee itself …

This approach overcomes one of the major limitations of an LCA, which is that it can be very expensive to conduct in full. ‘Gathering the data can be problematic, and the availability of data can greatly impact the accuracy of the final results’ …

This app simulates the pressure and flow inside an espresso machine while a shot is running. To view the effects of these changes in real time during a shot, click on ‘Graph’ and then ‘Start’, and the app will simulate an espresso being pulled, showing you how the pressure and flow change as the resistance …

We have engaged consultants and are devoting concerted time to examine all aspects of our business and to identify areas of improvement. This process of consultation will critically examine our hiring of freelancers and employees, our workplace …

Industrial grinders, of the sort used to produce espresso pods or supermarket packs of pre-ground coffee, are more or less exclusively roller mills. The most sophisticated of these grinders can grind coffee without significantly heating the grounds, and in the process produce very narrow …

Dr Adam Carr runs the Coffee Science and Education Centre at Seven Miles coffee roasters  in Sydney, Australia. Dr Carr previously worked as a researcher in chemical engineering, with a focus on high temperature water technologies, so it was …

If you leave a latte for a few minutes on the countertop, sometimes the foam starts to break up — but sometimes it doesn’t. Why? No matter how long you’ve been slinging shots, sometimes a latte will go bubbly after pouring. If you’ve ever had to remake a coffee because it was sat on the counter …

The coffee tasted vibrant and clean, and the salesperson showed me how easy it was to wipe away the residue from inside the portafilter — no more scrubbing away with a Scotch-Brite at the end of every day. The steel was a big selling point: easy to clean, more environmentally friendly …

Now let’s look at how the app can inform your own life-cycle analysis. As we learned in Lesson 1.01, the first phase of an LCA is Goal Definition and Scope. The scope of the app is limited to the carbon …

Aftertaste, in coffee, refers to the tastes and aromas left in the mouth after swallowing. Compared to other drinks, coffee flavours hang around for a long time: the aftertaste of an espresso can last up to 15 minutes (RJ Clarke and OG Vitzthum, 2001). Depending on the coffee, this may or may not be a good thing.

Received wisdom in coffee says that if you put a nickel, or a penny, on top of your puck after tamping, and lock the portafilter into the group and remove it again without brewing, you should just be able to see a slight impression in the puck from where the coin was pressed into the coffee.

One of our aims in producing this course is to provide the information and tools you need to analyse your own carbon footprint. This will allow you to see which changes will have the biggest impact and help you determine which interventions will be most cost effective. At the core of this …

A defining characteristic of an LCA is that it includes the impact of raw materials, production, use, and disposal, simultaneously. For example, a change of material could reduce the CO2 footprint from the manufacturing stage, but result in higher maintenance requirements or shorten the lifespan …

I would like to start this course with a short story. A confession of sorts. Come with me, as I go to my local cafe. I have forgotten to bring my KeepCup again, but I see they use compostable takeaway cups, so I don’t feel so bad ordering my coffee. While I’m there, I pick up a box of beans …

In our most recent instalment of the Advanced Espresso course, we discussed a surprising finding in the scientific literature: that increasing the brew temperature makes espresso shots run more slowly. We set out to test this for ourselves, and discovered that the truth is more subtle …