Home Roasting in the Corretto and making Torrefacto.
For those that have been to Spain, and have fallen in love with the Cafe con leche and the espresso, and have tried to reproduce the taste at home and failed, its not because you made it wrong, its because of the absence of one type of roasted bean in the mix. The sugar roasted bean at which makes up 10-30% of the blend, the Torrefacto.
Encasing the bean in sugar during roasting does two things. It preserves the bean for an extended life, and also uniquely cuts down on the acidity in the taste. This enables a strong tasting coffee without bitterness or the acid bite. I have found that my coffee consumption goes way up when I go to Mallorca or Spain, (and its high to start with ) yet gratefully I dont suffer from increased heartburn. There is something about the taste of torrefacto, so much so that I decided to learn how to make it.
It has taken a year. A year of reading, watching, visiting Roasters in Spain, researching history in USA and in France. It actually is such a simple process but……. too easy to mess up if you want to put the beans through your roaster without destroying your drum or pan with caramelised sugar.
If you have a fancy miniature drum home roaster, dont do this process in it. If you have anything you want to keep as is, dont do this in it. You have been warned.
The only methods of making this are in a metal bowl with a hot air gun, or a Corretto (breadmaker) and following instructions carefully. Im taking no responsibility for your frustration or tears or ruined equipment, thats just the way it is.
The commercial machines used to manufacture torrefacto, are dedicated machines for that job. They have special pouring mechanisms for adding the sugar and special cooling so as to quickly get the sugar to dry off on each bean and not clump together. This is a small unit, the companies in Spain usually use 300-600 kilo machines.
OK.. so here I will tell you how to do it in a Corretto. (This breadmaker is being stripped for a design Im working on..but it still works fine)
Pre heat the drum to 265C and add your green beans. (I roast Torrefacto in 300gram batches) Allow the beans to ‘dry’ by leaving them on the low setting of the gun for 4 minutes or so. (During this time you will see the temp rise about 4-6 degrees a minute). Once the temp is above 130C, watch for the beans colour change to yellowish..raise your heat rate to about 10 degrees C a minute. At about 175-185C add 12% of the green bean weight, of sugar, directly into the roasting beans. Close the lid and keep roasting. At this stage, your Corretto will smoke and smell of burning caramel and neighbours might be thinking that they should call the fire service. Ignore them.
Keep a wooden spoon handy in case you have to occasionally scrape down the sides of the corretto basket if one or two beans stick. DO NOT LOSE YOUR NERVE at this point. Its easy to get panicky when seeing a gloopy mess. If you have followed these instructions concerning weights, there should not be a gloopy mess, if you havent… it will take 2 hours of cleaning involving heat, sand and lots of elbow grease.
Continue roasting the bean of your choice in the pan, to the timings that you like for that particular roast. Now the last batch I did was Old Brown Java, and I like to dump them just at the onset of second crack, however this time I let second crack develop for 20 seconds or so and then dumped.
I dump onto flat roasting tins and shake for 30 seconds so nothing will stick. If Im roasting in the UK.. The weather will cool them off in double quick time.. Once cooled the beans are completely shiny, dry to the touch and no stickiness what so ever. If you crack one open, they look exactly the same as a normally roasted bean.
If there is any sugar left in your basket, and there should not be, just the odd fleck here and there, just proceed with your next non torrefacto roast and the basket will be perfectly cleaned.
I usually mix Torrefacto at a ratio of 20% by volume to the same single origin bean. If I am doing a blend, say 30% Old Brown Java, 20% Malabar, 20% Brazil, I will use 30% Torrefacto. (If I am going for the ‘full’ taste, I will make torrefacto out of Robusta, its a personal choice)
In the cup as an espresso, there is a gentle sweetness and decided lack of too much acidity whilst retaining the strength of the coffee. In a latte.. well I just make cafe con leche. A long pour of coffee and equal amount of steamed milk. It is my favourite milk based coffee.