Roasting Coffee Beans

[alien365]

I've recently bought myself a French press and have been ordering some beans online. I see the green beans are cheaper and to alleviate boredom I thought I'd look into roasting my own. Does anyone successfully roast their own beans without using an expensive roasting machine? I've heard popcorn makers work well at a fraction of the cost. Any experience or recommendations?

[OneeyedJohn]

Do you want nice coffee, or do you just want to save money.

[alien365]

1 hour ago, OneeyedJohn said:

Do you want nice coffee, or do you just want to save money.

At this moment in time I'd like both ???? I've spent a lot of money recently though which is why I thought I'd ask the question.

[Ponlamai]

I use a popcorn maker I got from an OP shop for $5. It works wonderfully well. I like a darker roast so I wait about 2 minutes till it starts to show a few glossy beans and I quickly cool them off in a large stainless steel bowl before grinding and putting through my espresso machine. The freshest coffee in the world. I also grow my own coffee here in Oz but the process from tree to roaster is complex, so I won't bore you with the details.

Best wishes

[Iamemjay]

Yeah. I've used a stovetop roasting pot, a popcorn machine and still have an (unused) benchtop home roaster.

 

It depends on what you are looking for. If you want quality, forget the lot of them. If you want to go to a lot of trouble and have a smoky, smelly cooking area, try doing it yourself.

 

What no-one tells you though is there is no way of dehulling the beans short of paying for it to be done commercially. This means that you will be grinding the beans with their hulls on. The grinder doesn't like it, particularly if you are using a mill (ie proper) grinder (The alternative being the cheaper, but far inferior blade variety.) This means that your ground coffee will be tainted by lots of small pieces of the hulls.

 

I eventually gave up and went to a local commercial roaster. For a small cost they dehull and roast my beans to my darkness specification and generally do a great job. The drawback here is that you need to take a decent quantity for it to be worthwhile both for you (cost) and for them (capacity of their roaster).

 

You may not end up with the "freshest" coffee in the world (That, in my experience is a statement of coffee snobbishness more than one of taste) but it will be worlds apart from your attempts at home roasting. (Tips: 1. If you are worried about freshness with long storage, just put it, properly sealed, in the fridge (NOT freezer) 2. Go to a coffee processing (ie pulping/drying) facility and buy a whole bag of green beans. Keep it in a dark, dry place in a hessian bag and it will keep for years.)

 

BTW I speak from the added experience of previously having had a coffee plantation and processing facility. I am still using left over and stored green beans years old, with no problems.

[bbudd]

Grow and roast my own coffee near Chiang Rai

The green beans are practical to store -they last a LONG time in storage

Easy to roast even in a heavy pan (I use cast iron)

Only thing to watch for is when they get up in heat you really have to keep stirring them or they'll  burn

They loose there flavor quickly after roasting so we just roast as needed

[Elkski]

I use a 1400 watt popcorn popper.  Modified.   I can easily do 100 grams. 

You cant roast beans in 2 mins.  A proper  roast profile takes 7-12 minutes.     I use the SS flour sifter mod on mine.  I tried just using the air chamber  and air stirring.   Only worked with like 20 grams.   With the sifter you get a good stir.  I have a metal cap on my sifter with a few strategic holes.  This keeps heat in and increases  exit velocity to blow out the chaff.I went in and disabled  the overtemp switch.  Can read about this online.  I drilled an extra 5-6 0.25" holes in bottom base for better airflow.  Using a popper requires  a length of extension cord to lower the voltage,  thus wattage.    In usa we have 120 v power.  Not sure how they model the 240 v units.    I always use outside.  I had a few  burn out after as few batches.  Not sequential.  .   Since I drilled the extra holes this unit has cooked 40-50 ,batches.  Green beans not so cheap  here.   I have ordered from sweet Marie's in California.   And bought at local roasters.  But roasted  beans  lower  cost at the store.   Lately I've been paying about 5-6$/# roasted  at Costco.  

 

I use a 50' 14 ga extension cord.    I brought home a couple kg of beans from CR in Jan.   But they roasted so poorly.  I've never had beans act like this they had no chaff that would come off so it ended up in the grind. The first crack was not very evident in the second crack  did not occur all the time.  I prefer a medium roast medium to dark roast so basically you go maybe a minute after first crack sometimes just till I hear second correct starting and then pull the beans and pour them into a stainless steel strainer and then tumbled in between the strainer and a stainless steel screen strainer.  I checked my units temperature profile  and it was pretty much what you look for using a thermocouple probe.   There is a whole science behind coffee roasting and chemical reactions occur at different stages of the cook. 

 

My chaff comes off 95% on beans I buy here.  Maybe those beans from CR had a step  missing.  I did buy them direct off a drying roof in the hill tribe area.   The CR beans seemed like they had a dry growing year was my guess.    I have had excellent results.  I freeze  my green  beans in steady temp (no defrost  cycle ) deep  freeze at -5f.  I finally got a burr grinder.   Hands down dont get a blade.    Yiu must cook outside the smell and smoke  is to much without ventilation.    Fast cooldown is important.  I'm no expert. Only roasted maybe  30 # total last 5 ,years.   

Edited May 19, 2020 by Elkski

[snowgard]

I use my oven on 200°C with air flow and make direct 2 trays. So it's around 700-800g mixed Arabica & Robusta beans. It need around 20 minutes. The last 5 minutes I stand by and look that the beans are not to dark because than the taste will be more bitter. Then I take out the trays and pour the hot beans in a big metal bowl, take another with, go outside and throw the beans from one bowl to the other. It's a dirty job because the rest skin gone out of the beans.

And not forget to open all windows!!! ????

 

I like this coffee more as the ready roasted beans.

Green coffee beans you can buy on Lazada.

https://www.lazada.co.th/shop-groceries-beverages-coffee-coffeebeans/?from=suggest_normal&page=1&q=green coffee beans&sort=priceasc

On youtube you can find a lot of instruction videos.
 

Edited May 19, 2020 by snowgard

[LukKrueng]

On 5/16/2020 at 7:01 PM, alien365 said:

I've recently bought myself a French press and have been ordering some beans online. I see the green beans are cheaper and to alleviate boredom I thought I'd look into roasting my own. Does anyone successfully roast their own beans without using an expensive roasting machine? I've heard popcorn makers work well at a fraction of the cost. Any experience or recommendations?

I am NOT an expert on coffee matters, but a good friend of mine IS. He used to work as an organic coffee plantations advisor and his master degree thesis was a research of quality of coffee beans grown in different environments. He is also a trained barista and a coffee taster. 

I visited some of the plantations he was working at, the green beans storage facilities, and the coffee processing centers (from tree to green beans).

What I learnt from him was that apart from the precise growing and drying process, the other very important step for a great coffee is the roasting process. There are commercial roasters that just roast, and the more professional roasters that take into account all the steps from growing environments, pealing process, drying process and aging of the green beans and select the best roasting method for those beans. The association he was working for sent the beans to a highly accredited roaster.

All said above is in regards to Arabica specialty coffee (similar to single malt vs blended whiskey...).

So I guess if you are looking for a really good quality roast - doing it yourself won't really do it.

 

All that said - I have a few Arabica plants (growing not in the best environment ie wrong altitude) so whenever in the future I get some fruit I might try to dry 'em and roast 'em just for fun...

[alien365]

4 hours ago, Iamemjay said:

Yeah. I've used a stovetop roasting pot, a popcorn machine and still have an (unused) benchtop home roaster.

 

What no-one tells you though is there is no way of dehulling the beans short of paying for it to be done commercially. The grinder doesn't like it, particularly if you are using a mill (ie proper) grinder. This means that your ground coffee will be tainted by lots of small pieces of the hulls.

Would this be a problem using the French press? I'm relatively new to the 'proper' coffee, but I think my last pack of Ethiopian beans had a fair bit of husk on. Maybe due to it being medium roasted? 

 

Would drying the seeds in the sun after roasting make it possible to remove the husk?

[alien365]

Thanks everyone for your responses so far. It's good to see that there are people who have experimented on this too. 

 

I'm wondering if any of you have managed to achieve an even roast through practice in your techniques. That seems to be one of the biggest problems from reading on the net.

 

In the meantime I've just bought some roasted beans to try from D'Oro as I'm nearly out of my Brazilian beans.

 

[Iamemjay]

3 hours ago, alien365 said:

Would this be a problem using the French press? I'm relatively new to the 'proper' coffee, but I think my last pack of Ethiopian beans had a fair bit of husk on. Maybe due to it being medium roasted? 

 

Would drying the seeds in the sun after roasting make it possible to remove the husk?

As I have not used a french press for many years - since I started growing, roasting etc - I cannot say definitively, but my guess is that this would be less of a problem than with an expresso machine, because the french press does not require as fine a grind.

 

The roasting is done at very high temperatures, far higher than the sun would provide, so the answer is no. 

 

One other thing I neglected to say is that I agree with the comment in another post re even-ness of the roast. It is virtually impossible to achieve a uniform result. This was so even with my benchtop roaster which has a mechanical stirrer.

 

Another problem is that unless the husks are removed before roasting it is much more difficult to identify the stages - first crack, second crack etc - of the roasting process.

[alien365]

Seem as though the green beans can last so long I think I'll buy some and play around with them. I'll try some on the hob and buy a popcorn maker. I'm happy to modify it and drill a few holes like Elksi mentioned if needed. I'll keep buying and drinking my pre-roasted beans though at the same time.

 

That being the case does anyone know of the most friendly size of coffee bean to self roast? That way I'm more likely to succeed. There's no point me buying size 18 upwards if they're troublesome to roast.

 

For information I'm really enjoying my French press and trying out different beans and ratios. It's such a refreshing change from the instant coffee I used to have at home and better than nearly all of my local coffee shops. I've even used it to make some microfoam (or something similar) to go with the coffee.

[jumlong]

On 5/19/2020 at 11:25 AM, Elkski said:

Using a popper requires  a length of extension cord to lower the voltage,  thus wattage. 

Incorrect!

Watts are Watts.

The formula is Watts=Volts x Current (Amps).

If you use a long extension lead, you will lower the Voltage TRUE it's called Voltage drop and the amount of drop will depend on Length of lead and load (watts). But you will increase the current (Amps) Because Watts are always the same. Watts are Watts.

If you want to control the amount of heat generated by a 1,800 watt popcorn maker I would do this.

Get a Thermistor Not a Thermerstate . A Thermister is the control used on an electric stove (cooker) that has elements (hot plates). It controls the heat generated by the element by switching the element on and off. Like a Timer. When a Thermistor is on High the element is on 100% of the time.When it's set to say setting "5" the element is on 50% of the time (1,800 watts) and off 50% of the time (0 watts) thus generating less heat. But it doesn't control the maximum heat. A thermostat would be needed to control Maximum Temperature like in an electric oven. A thermostat is most likely impractical to retrofit to a popcorn maker as you would need to get the controlling temperature probe amongst the beans and it would cost a lot more. Get an electrician to mount an electric stove Thermistor control into a junction box.The cable from the popcorn maker into one side of the junction box and your supply cable into the other. And keep all cables as short as practical. You can then experiment with different setting on the Thermistor like on high for 10 min and then reduce to say 5 for 10 minuets use your temperature probe as a guide.

[jumlong]

I tried to edit my post but it says I can't

So here is my edit.

It concerns me, you have disconnected the over temperature switch.This tells me you are exceeding the maximum design temperature of the popcorn maker.

Reconnect it!

You could simulate a Thermistor by switching the unit on for 10 min, then switching it off for 30 sec then back on for 30 sec the trick will be. Do not leave the unit on long enough for the over temperature to switch the unit off.

Remember, if the over temperature is disconnected there is a very high risk of a fire

[jumlong]

I need to make another correction.

I said Thermistor I meant to say Simmerstat

Change Thermistor to Simmerstat.

 

[alien365]

Well I gave it a go and bought some Colombian beans to roast. My first attempt was in the pan and I think it went ok. I felt it difficult achieving an even roast but that could also have been due to the amount I roasted in one go (200g).