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--- blog:coffee_blog:2022-05-15 [2022/05/21 12:01] – [Cooling] Phil Ide
+++ blog:coffee_blog:2022-05-15 [2022/07/24 10:05] (current) – Phil Ide
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-====== 2022-05-15 ======
+====== Coffee Blog: 2022-05-15 ======
 [{{ :blog:coffee_blog:yuchengtech_roaster.jpg?direct&400|flat roaster}}] In 2021 I decided to take my love for coffee a stage further. For quite a few years I'd been making my own blends from pre-roasted beans, and that had met with varying amounts of success (as you can probably imagine). That is until I started getting serious with it and making charts with the various flavours and notes I perceived and what the strengths were of these and whether they were desirable or not. For example, I might taste a berry flavour, and depending upon how strong that flavour was I'd give it a numerical value. If it was undesirable, it was a negative value.
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 That said, the chaff can make a mess of your grinder - which should definitely be a burr grinder, not the blade type. Beans should be crushed, not chopped. If you think it makes no difference then ask any cook about the difference between chopping or crushing garlic.
-I need to resolve the issue of being able to roast coffee in smaller amounts. Enter the Gene Café.
+I needed to resolve the issue of being able to roast coffee in smaller amounts. Enter the Gene Café.
 ===== Drum Roaster =====
 [{{ :blog:coffee_blog:genecafe.jpg?direct&400|Gene Café off-axis drum roaster}}] This machine takes a maximum load of 250g, as opposed to the 250g minimum load of the flat roaster, meaning I can roast smaller quantities with ease. The drum is off-axis, so as it rotates it also tips with one end down and ending with the other end down. This ensures the beans don't get stuck in part of the drum, and also helps to ensure they are continually mixing amongst each other. Partitions inside the drum force the beans to roll and jumble rather than just sliding as the drum rotates.
-Another major feature of this machine is that it has an exhaust. You can see this at the top of the black box-like structure on the left. That structure collects huge amounts of chaff, another excellent feature. I attached a pipe reducer to the exhaust which took reduced from 100mm to 80mm (the size of the exhaust), and then attached a 100m expandable metal ducting tube which carries all that nasty steam, oils and aromas out of the kitchen. By the way, if you think roasting coffee smells of coffee, you're mistaken. It smells of cooking hay, or possibly peanuts.
+Another major feature of this machine is that it has an exhaust. You can see this at the top of the black box-like structure on the left. That structure collects huge amounts of chaff, another excellent feature. I attached a pipe reducer to the exhaust which expanded the bore from 80mm (the size of the exhaust) to 100mm, and then attached a 100m expandable metal ducting tube which carries all the nasty steam, oils and aromas out of the kitchen. By the way, if you think roasting coffee smells of coffee, you're mistaken. It smells of cooking hay, or possibly peanuts.
-This machine is by no means a perfect machine. Although it has digital temperature control, it measures the temperature of the exhaust. A good machine will also measure the temperature of the beans. Comparison of these two measurements tells you what is going on inside the roasting chamber much more than eyeballing the colour of the beans, and allows you exquisite control over the roasting process. As it only measures the temperature of the exhaust, you still have to eyeball and use the exhaust temperature as a guide.
+This machine is by no means a perfect machine. Although it has digital temperature control, it measures the temperature of the exhaust. An excellent machine will also measure the temperature of the beans. Comparison of these two measurements tells you what is going on inside the roasting chamber much more than eyeballing the colour of the beans, and allows you exquisite control over the roasting process. As it only measures the temperature of the exhaust, you still have to eyeball and use the exhaust temperature as a guide.
-All that said, it's not cheap, but a lot cheaper than one of those machines that can read both temperatures. I have neither the space nor the money for one of those things, and they're best setup in a shed, garage or basement - none of which I have. Still, in nice weather I can take the machine outside avoid any of the nasty smells filling my home.
+All that said, it's not cheap, but a lot cheaper than one of those machines that can read both temperatures. I have neither the space nor the money for one of those things, and they're best setup in a shed, garage or basement - none of which I have. Still, in nice weather I can take the machine outside and avoid any of the nasty smells filling my home.
 ===== Roasting Temperatures =====
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 The third phase is known as the development phase, where all those lovely flavours created by Maillard reactions in the browning phase are further developed. Some people stop early in this phase, for a fruity, yet tea-like coffee, other people go to the end of the phase, second crack. Second crack occurs when CO2 is released and the bean expands, causing yet more damage to the attachment the chaff has to the bean. These cracks are quite audible, and sound not too dissimilar to popcorn.
-It is possible to keep roasting, but after second crack the acids that provide many of the interesting flavours are destroyed and a cleaner, roasted coffee flavours ensues - great if that' what you want, even better if you're aiming for a bitter espresso (FYI Italian generally roast their espresso light than this).
+It is possible to keep roasting, but after second crack the acids that provide many of the interesting flavours are destroyed and a cleaner, roasted coffee flavours ensues - great if that' what you want, even better if you're aiming for a bitter espresso (FYI Italians generally roast their espresso light than this).
 There are more phases, these are just the broadest and most significant.