Immersion — Final Assessment

BH Unlimited Update, Apr. 10th, 2021.

In the last updates, Unlimited subscribers had the opportunity to attempt the final certification of the Coffee Buyer’s Guide to Guatemala. This time around, it’s the Immersion course that has been finalised, the last i’s are dotted and it’s good to go. Here’s a link to the Final Assessment:

How to make the best after lunch coffee you’ll ever taste, that looks and smells like a capsule coffee but doesn’t create any micro plastic pollution.

If we had to pick a favourite brew method of all those we’ve profiled in the Immersion course, it would have to be the cezve (ibrik). But have you ever noticed just how similar cezve coffee and capsule coffee are? In our experience, the average extraction yield for both brew methods is up around 24–25% (very high). Moreover, the brew ratios involved with both methods are practically identical. 1:8 is a typical ratio for preparing a strongish cezve. That’s almost exactly the ratio you get if you press the little button on a typical capsule machine — where you end up with somewhere around 40g of espresso produced from a little over 5g of coffee grinds in the capsule.

Ingredients -  10g of coffee and 80g of water. Preheat your water to 60°C.

Method -  With cezve it’s that exact ratio you find with capsule coffee that we recommend using; just double the size: 10g of coffee and 80g of water as a starting point. (Use a little more coffee if you like. The cezve equivalent of a ristretto works brilliantly, too. Although 1:6 is about the limit we’d recommend for brew ratio). Preheat your water to 60°C. Pour the preheated water into the cezve. Drop in the coffee grinds and give 20 stirs with a teaspoon or a quick whisk for ~10 seconds. Put the cezve straight onto a low/medium gas flame. Use the smallest hob you have. (If you have a sand heater, that’s even better). Monitor the temperature with a small digital thermometer, ensuring the tip of the probe is not touching the bottom of the cezve. Remove the cezve from the flame once the slurry is between 88–93°C. 90°C is about right. Don’t go too hot — it’ll boil over. Cezve can acquire that same unfortunate flavour you get from leaving drip coffee on a hot plate for too long if you allow the brew to go much over 93°C.

Polishing -  An optional, but very much advised final step: Pour the entire contents of the cezve through a pre-rinsed filter paper. It will take about 60 seconds to draw down. The end beverage will be just as transparent as a normal pour-over with a TDS close to 3%. That’s a level of strength almost exactly the same as capsule coffee but there’s no plastic waste, no turbidity, and it’ll taste absolutely delicious.

Final Tips -  We have found that cezve works particularly well with long fermentation coffees: naturals, anaerobics, hot fermentation, CM coffees etc. If you go with a traditional approach and don’t filter, wait a good 5 minutes before attempting to drink the beverage. It needs the time to cool and for some of the suspended solids to separate out.


New Posters

Celebrating the end of a big journey into Immersion brewing with a free poster series. Here's the first poster available for download - French Press !


Decision Tree

We have published several new lessons in the Decision Tree — our free course that helps baristas and café owners make informed decisions about how to operate in a world beset by climate change. For anyone who is not subscribing to the BH Unlimited service , if you visit the course syllabus page, you will notice all the lessons are unlocked.

The new lessons investigate the environmental impact of everything that happens once a coffee reaches the consuming country: roasting, packing, brewing, drinking, and waste disposal. These are the stages in a coffee’s life cycle where roasteries, cafés, and consumers can have the biggest impact, by making smart choices.

The data we present help us answer questions like this one:

Which brewing method is the most environmentally friendly?
• Espresso
• Ready-to-drink coffee
• Instant coffee
• Batch brew

Have a think about this one, and see if you can guess.

The answer is instant coffee. Instant coffee doesn’t fit our mental image of what an environmentally friendly process looks like — but understanding why it is so efficient can help you make better decisions about whatever brewing method you use.

The main reason is that instant coffee manufacturers extract as much as 60% of the bean, so you can make around three cups of instant for every cup of brewed coffee. The other factor is that to make a cup of instant coffee, you can heat just enough water to drink, and no more. This tells us that getting the most out of every gram of coffee, by extracting high and reducing wastage, and limiting the amount of hot water you use, are the two most important factors that will make your brewing more environmentally friendly.

Another contentious issue for cafés to wrestle with is the use of disposable cups. Many cafés have switched to compostable plastics, or even started refusing to use disposable cups altogether, in an attempt to be more environmentally friendly. However, there isn’t clear evidence that these actually have any benefit.

Most studies show that compostable plastics produce more greenhouse gases than traditional plastics do — no matter whether the conventional plastic is burned, recycled, or sent to a landfill ( J Vendries et al. 2018 ). And whether washing reusable cups is preferable to using disposable cups, depends on the efficiency of the dishwasher. According to one review of the available data ( Heller 2017 ), ‘Most studies are generally inconclusive or lean toward disposable options being better’.


Immersion - New Lessons!

Baseline Testing:
IM 7.06 • Final Assessment
IM 7.07 • A Final Word

The Decision Tree - New Lessons!

Gathering the Data:
TDT 2.07 • Roasting
TDT 2.08 • Packaging
TDT 2.09 • Transport and Distribution
TDT 2.10 • Styles of Consumption
TDT 2.11 • Waste Disposal
TDT 2.12 • Recap and Glossary
TDT 2.13 • Comprehension Test


As always, we're just an email away if you have any queries! Have great weekends and we look forward to seeing you next time.



To the Boundaries of Coffee,
Team BH

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