Mini Oven Roasting

(one amateur home roaster's perspective)

Firstly - there are other resources available on the net, if you want to roast in your home (kitchen) oven. Gas or electric, there are guides to both. Most people have access to a kitchen, and it may suit you to roast like this. But…

This article doesn't aim to cover that method. Its scope is an overview of a smaller-scale, portable method which makes use of a mini electric oven and a little skill. It's suitable if you:

  • Want to try out home roasting, without a big investment
  • Need your kit to take up little space when you're not using it
  • Can't or don't want to roast in your kitchen - most likely due to the smoke or smell

a bit of background -

Roasting coffee by any method will produce smoke. But my major issue when home roasting is the smell; nice during the roast (if you like it), but overpowering afterwards - and therefore a bit antisocial to do in your home.

I started out roasting in a heavy-bottomed saucepan, in the kitchen, stirring with a wooden spoon. This method is really smoky, i think because it's a bit uneven - so some beans are burning while you're waiting for others to roast. Even with kitchen window open and extractor fan on, our flat smelt of burning lentils for a couple of days after each roast.

Quite rapidly my flatmates told me they weren't happy with this; i would have to find another method. I'm glad they did - my solution is easier, more even, and less smoky - and the roasts are better too.

the criteria -

So I had to have a portable method, one I could use in the shared utility room with the windows open then tidy away easily. It also had to be practical, fun, and affordable!

That is:

  • portable
  • affordable
  • and capable of even roasts under supervision*

*ie the method must reward the attention you give it, without demanding total attention! It mustn't ruin good coffee!

the solution -

I spent £20 on a mini oven from argos, and found a roasting tray to fit in a charity store. The oven has two heating elements and a glass flip-down door at the front. I've used both elements (top and bottom) whenever I roast.

You can see the roast easily, and most importantly, you can stir the beans without removing them from the oven; just open the door, reach in with a fish slice and stir, then close it up again.

As it's an electric oven, with no fan, it's important to dissipate the heat from below - this will make the roast more even. My oven comes with a roasting tray / shelf, which I use for this - it's positioned about 1/4 the way up inside the oven. I then put my tray for beans on the wire shelf, about halfway up.

You could call it a glorified toaster, or your very own radiant-heat roaster - whatever you like!

method details -

(what I do is this)

Assemble my mobile roasting kit:

  • mini oven
  • roasting tray
  • 2x metal colanders
  • metal fish slice
  • tea towel
  • beans (small batches, up to 125g with attention)

Take kit to little-used, well ventilated area - eg porch, shed, utility room. Or outside, if you have a power supply.

  • preheat oven to ~230C, with roasting tray inside
  • take tray out and spread beans on it (layer about 1-1.5 beans thick)
  • put in oven, then read something interesting / stare at wonderful coffee roasting
  • every 3 min or so, flip oven door open, stir beans quickly, without taking tray out (fish slice does this v well)
  • stir so as to swap beans around, middle and sides

I get quite consistent roasts -

  • grassy smell at 5-6 minutes
  • first crack at 9-11 minutes
  • second crack at ~15 minutes (if I'm roasting decaf / going to second crack)

Then tip out into colanders and cool (pour one to the other in the breeze, blow away chaff). Tidy away kit, pack and rest coffee, then enjoy.

It may not be the most rarefied method, but it's fun, portable, and rewards a little attention with, I think, really good coffee. If that sounds good - give it a go!

-trip, 2009.

Useful links (external):

Home Roasting Coffee in an Electric Oven

Oven Roasting Step by Step - MATS LEIDÖ

Sweet Maria's oven roasting method