Coffee Roasting: A Guide to Roasting Coffee Beans

Having enjoyed freshly-brewed coffee for many years, I thought I would have a go at roasting my own beans. There are several ways to this including simply baking on a tray in a hot oven. However, I wanted a method that was a bit more predictable and repeatable so plumped for a slightly more ‘high tech’ option. I bought this roaster from Amazon though other suppliers are available. This machine is also great for roasting peanuts, pecans, hazelnuts, etc. It will probably do popcorn and is very easy to clean thanks to its ‘teflon’ lining.

I get my green coffee beans from Rave Coffee; they have a good selection at reasonable prices. A while ago I suggested they include roasting suggestions (e.g. medium or high roast) and flavour notes with their green beans and I’m glad to say they now do.

I roast 500g batches of green beans; sufficient to last me about two weeks (one large cafetiere/day). Yesterday, I roasted some Sumatra Mandheling beans using my standard operating procedure (SOP).

First, set up roaster outside because it can generate quite a bit of ‘smoke’ depending on the type of beans. Pour the green beans into the roaster, replace the lid, set the temperature to 200°C, switch on and start the stopwatch.

After 10 minutes, increase the temperature to maximum (240+ °C) for a further 10 minutes. Note: I have measured the ‘actual’ roasting temperatures with an infra-red thermometer and find they are about 20°C below the marked temperatures in this particular roaster.

At around 20 minutes, you can hear the ‘second crack’ - at this stage, you have a medium roast coffee; my preference because it brings out the individual flavours of beans from the different sources and processing methods used to prepare the green beans.

Roast for another 1-3 minutes for a ‘medium-high roast’ or 4-5 minutes for a ‘high-roast’ though timings will vary depending on the machine. For high-roast, the coffee beans will become oily as well as darker. Part of the fun is experimenting with different roasting temperatures and times.

As soon as you have the degree of roast you want, you need to cool the beans as fast as you can to prevent ‘overcooking’. I do this by transferring the hot beans to a colander and then removing the ‘chaff’ by pouring the beans from one colander to another; a gentle breeze helps.

The roasted beans are left to cool before transferring to airtight containers. I’ve been told that some ‘outgassing’ from the roasted beans may occur but I’ve never found this to be an issue. To be on the safe side, you might want to leave the lid off the airtight container overnight and/or periodically open and shut the container.

Final Product

The roasted beans are not a uniform colour, thought this variability is less for high-roast coffee beans, due to inefficient mixing and uneven heating in this particular roaster. I quite like this quirk because it results in more complex tastes and flavours and every pot of coffee is different. These Sumatra Mandheling beans resulted in an earthy, spicy taste with a hint of fruitiness (I couldn’t tell you which fruit though!).  

Coffee from freshly-roasted beans is far superior to anything bought from your local supermarket though it can be a little more expensive. Ideally, roasted coffee beans should be ‘drunk’ within a week for the very best flavour. If you like coffee and enjoy trying something new then why not give it a try.

Spotted: Garden Carpet Moth

Garden Carpet moth spotted on the cucumber plants in the polytunnel. Very common in the UK but has a preference for gardens.

Comfrey Tea - How to make your own liquid fertilizer

Comfrey is an essential plant to have in the vegetable garden if you have room. It needs to be controlled or it will spread everywhere. I was given a small piece of root (Russian Comfrey) by a friend a few years back which I planted out in autumn about 10-15 cm deep and just waited; the following year I was using the leaves as compost accelerator and making comfrey tea liquid fertilizer. This was my plant in the middle of May 2020.

It is an attractive plant producing lots of pinkish flowers that the bees absolutely adore. It is also a great source of NPK nutrients with levels not dissimilar to commercial tomato feed when made into comfrey tea (see below). For other useful facts and information on growing and using comfrey, see https://www.allotment-garden.org/comfrey/growing-using-comfrey-for-gardeners/. 

Be warned that comfrey tea smells and I wouldn’t describe it as a pleasant smell. Nettles can be used in place of comfrey for your ‘tea’ and I’m told the brew does not smell as bad; you could, of course, use a mix of both plants. However, I do not have space for a nettle patch sufficiently large for this purpose. If you have room for a nettle patch then go for it - many common garden butterflies (e.g. small tortoiseshell, red admiral, comma) lay their eggs on stinging nettles.

How I make comfrey tea

The basic principle is to soak comfrey leaves/stalks/flowers in water for a minimum of two weeks. You can make a ‘ready-to-use’ (i.e. already diluted) version in a water butt; see link above. However, because of space restrictions, I make a concentrate for dilution later. To do this fill a container full of chopped leaves/stalks/flowers, cover with water, add a weight to keep the plant material submerged and leave in a quiet corner. Always use a container with a tight-fitting lid as this avoids the odour annoying the neighbours.

I use an old Bokashi composting bin which comes with all the necessary features: a tap for drawing off the compost tea, a course filter to prevent leaves blocking the tap and a close fitting lid.

Using scissors, trim the comfrey plant and roughly chop into the bin until full - leave some flowers on the plant for the bees. Place a weight on top (I use an old roof slate recovered from the kitchen garden excavation), fill with water to the level of the weight and put the lid on. Leave for a minimum of 2 weeks. Dilute as you would any commercial tomato feed; typically 100 to 200 to 1 dilution.

You might want to use another plant food for indoors as the odour does not present a welcoming atmosphere. But for the garden, you do not need to buy plant food. Use this brew with homemade compost and biochar (more on these later) to maintain the fertility of your garden.

The Garden - Planning and making a start

The existing garden was simple and functional but with too much car parking space, a lack of privacy off the main highway, not enough colour (e.g. flowers) and no greenhouse or kitchen garden. There was a small patio area, where we had enjoyed a glass of wine with the previous owners while discussing the house purchase, and a very solid raised brick fish pond with a number of ‘sitting’ tenants.

We had a sort of plan that was really just a list of things we did or did not want in the garden:

(i) The lawn had to go - we are not fans of the greensward.

(ii) A larger patio area suitable for all year round use.

(iii) A fence/gate at the entrance of the property to give some privacy while leaving two car parking spaces.

(iv) The fish pond had to go along with its inhabitants - we really did not want the responsibility of caring for the twenty or more fish which, in any case, were largely invisible most of the time.

(v) The extra land was purchased with the intention of creating a kitchen garden so a small greenhouse was essential for raising plants and harvesting crops such as cucumbers and tomatoes.

(vi) Do something with the small courtyard at the front of the house.

Most of the effort in the first year (2002) was spent clearing the kitchen garden of brambles and weeds then digging out the builder’s rubble to a depth of two to three feet. Soil was sieved to recover as much as possible though it would still be necessary to buy in topsoil for the raised beds. Scaffold boards for the raised beds were ordered from Lincolnshire; the delivery lorry was too large to get down the narrow streets so the boards were carried the last 100 yards to the property. Topsoil was ordered from a local company (Radbournes) and paving bricks for the path from ‘I cannot remember where’.

Unfortunately, we cannot find any photographs of the kitchen garden in its very early years. The picture below was from April 2007 so the kitchen garden had matured a little. It looks like I am in the process of re-laying the paths and the garden is being prepared for the growing season; still some leeks to harvest and the chard/beet has bolted! In the top right-hand corner, the Red Windsor apple tree is coming into blossom along with the crab apple (top centre).

The flower garden had to make do with a cheap and cheerful makeover for the moment. Fortunately, there was a ready supply of house bricks from the kitchen garden excavation, the fish pond demolition and, mysteriously, behind the summer house. These were put to good use as borders to existing beds as well as building a standalone circular flower bed. This photo is from a snowy day in February 2004.

The patio was installed in 2003 by Turfcare Landscapes Ltd. The original lawn has gone; now covered with forest bark, a few added bushes/plants plus the ubiquitous trampoline.  In the background is the ‘summer house’ affectionately known as the ‘bus shelter’. Facing west it was a great place to sit and watch the sunset. The circular brick-bed can be seen in the middle of the picture and on the far wall is the greenhouse we brought from our previous residence. Next to the ‘bus shelter’ a patch of lawn - perhaps better described as a ‘close-woven mat of weeds’ - was brick-lined, the turf cut with a spade and inverted (soil upwards) then sown with wildflower seeds. In later years, it gained various other plants/bushes and doubled as the pets graveyard. 

Moving ahead to April 2007, the garden has developed a bit more character and colour. The new greenhouse (Homebase - top right) was put up in 2004. The ‘bus shelter’ was carefully taken down in 2006 and donated to a friend.  In its place, Andrew built the shed (or more correctly, Art Studio) from scratch and also installed the fence/gate at the side of the property to provide some privacy. 

The only other noteworthy addition to the garden before 2007 was at the front of the house where a not-unattractive wall separated a small concreted front garden from the public highway.

The wall was causing damp ingress into the house so we took the opportunity to rebuild it while incorporating some dampproofing measures. We found a local builder who would include a ‘flower bed’ in the top of the wall. The display in the wall changes with the seasons and from year to year; see examples below:

In the next article charting the development of the garden, we will look at the newly acquired ‘Secret Garden’, expansion of the main flower gardens and the redevelopment of the kitchen garden to include a polytunnel and hot composting facilities.

The Garden - Beginnings

We moved into the house and garden in November 2001. The garden measured 18 metres long by 10 metres wide and was south-facing. The original garden for this house was approximately twice this size but more about this later.

This photo is from the original sales brochure and taken from the south boundary of the property. The garden was described as an area 60 foot by 30 foot shared between car parking, lawn with shrubs, a raised fish pond (bottom left foreground) and a summer house (behind the photographer). 

The Garden circa 2001

An option to buy some additional land (10 metres by 12 metres) at the rear of the property from our next-door neighbour was too good an opportunity to miss. This plot was, in fact, part of the house’s original garden. There was still a smaller plot (12 metres by 4 metres) that our neighbour did not want to sell because, he said, the larger area (14 metres by 12 metres) was sufficient to build a house on! We never found out whether this was true. But in March 2007 we bought the smaller plot and finally restored the garden to its original dimensions.

Now the hard work began. We had already decided the garden area in the photograph above would be the flower/ornamental garden while the additional 10 x 12 metre plot would become the kitchen garden. This turned out to be harder than we thought.

The proposed flower/ornamental garden had a solid underbase of scalpings  - even the lawns were just a couple of inches of soil on top of scalpings. The scalpings would need to be removed to provide a decent depth of soil for planting so out came the pick and shovel. It did mean individual raised beds would be the order of the day rather than removing all the scalpings.

An even greater shock was in hand when we started digging in the kitchen garden. First, we had to clear the overgrown brambles and, only then, did we discover the whole plot was a rubbish dump. The story we were told was that the plot had been dug out with the intention of installing a swimming pool; after this did not materialise it became a rubbish pit. It took at least eight 4-yard skips to take away the toilets, drainage pipes, bricks, tiles and other building materials by which time the garden level had dropped considerably.

In the next post, we will describe the first incarnation of the gardens.

The 'Aviary'

About a year ago (early 2019) I knitted a thrush from this lovely book:

Knitted Birds by Nicky Fijalkowska

This year he has been joined by several friends, also from the book and there are some more to come. 

The hoopoe is a bit exotic but they have been seen in Herefordshire.

So far then - thrush, magpie, sparrow, barn owl, hoopoe, tufted duck.

Look out for a robin, blue tit, woodpecker and maybe a nuthatch (but I’ll have to make that one up, it isn’t in the book!)

The guitar is one I’ve played in Bandemonium for over 12 years. It got damaged, scratched, worn and I got a new one but couldn’t bear to get rid of this one. It’s now got a new life and I like it on the wall.