Roaster Focus: How to Choose the Right Size Roaster for your operation

Friday, 15 January, 2021

Every month we will be featuring an exclusive blog from Neil Maree, owner of Genio Coffee Roasters to expand your knowledge of these machines and give you some insight into the coffee industry. We already learnt so much from this first piece! Take it away Neil...

Coffee roasting is as much a science as it is an art.

I am Neil Maree. I am an engineer and the founder of Genio Coffee Roasters.

My passion for engineering and the love of coffee was cultivated at the University of the North-West, South Africa, where my final year engineering project ultimately led to me to build a coffee roaster. I started developing machines full time and Genio Coffee Roasters was founded in 2011. At Genio we are now celebrating our first 10 years in the coffee roasting industry.

My topic for today is how to decide what size of roaster you need to buy to suit your roasting needs. This decision requires a balanced approach as there are many variables to consider. In my experience, prospective buyers often ask for the incorrect size because they have not carefully considered their target market nor have they done a forecast of what they will be able to sell. 

Investing in a roaster which is too big can be as counter-productive as investing in a roaster which is too small. As much as you need time to roast, you need time to sell and you have to be able to sell what you have roasted. As a commercial coffee roaster, you are in business to make money and to serve your customer base at a sustainable level. This is where you need to hit the sweet spot in order for your business to turn over. Always remember that selling equals making money!

Pictured here are (from left to right) examples of a 3kg, 6kg and 15kg roaster set up. The cyclindrical piece of equipment in the centre is a de-stoner.

Here goes the math behind the roasting! I have devised a calculator to aid you in making an informed decision when you consider the size of the coffee roaster you are planning to buy. My calculations are based on the 1kg, 3kg, 6kg, 15kg and 30kg roaster sizes – the micro roaster (1kg to 3kg), small commercial roaster (5kg to 15kg) and the medium commercial roaster (15kg to 30kg).

 {Ed's Note: Current Exchange Rate is $1 = R15,18}

In Table 1, you can see that a 1kg machine is totally inadequate to earn a salary of 3000 USD per month.  A 6kg roaster will work, but you’d need to sell 2600x 16oz bags (1190x 1kg bags) to make your salary, which leaves you with only 88 hours per month to do active selling.  With a 15kg machine, you’ll have 128 hours left (16 days out of the month if you actively sell for 7 hours per day).  This is quite easy to achieve and your business will grow quickly since you are spending 2 weeks out of every month actively selling and promoting your brand.  So, in this scenario, a 6-15kg will be sufficient given your expected salary income.

I have put together further scenarios to illustrate the math:

Scenario 1: I want to roast for my own coffee shop that consumes 20lb of coffee per day.  I also sell a few bags retail to my walk-in patrons.  I previously bought roasted coffee at $18/lb.  What size roaster do I need to buy?

Recommendation:  With a 6kg machine I’d need to roast for 59 hours per month.  I’d rather get a 15kg machine and only roast every Monday for 6 hours.  Then my coffee will be degassed by Friday, ready for the weekend rush.  Yes, the capital expense is more.  But do I really have another 59 hours to spend away from the shop, busy roasting?  Probably not.

Scenario 2:  I used to earn 4000 USD per month at my corporate job.  I now want to have my own business.  How much coffee do I need to sell to sustain my lifestyle?

Recommendation:  This is a new business and I can invest all of my time into it.  A 6kg machine will be adequate as I’ll still have 66 hours (8 days) per month left to sell.

Scenario 3:  I currently have a 6kg machine roasting, but I’m just too busy.  I’m making good money, but I spend most of my time behind the machine.  If I upgraded to a 15kg machine, how much more time will I have per month in order to run and grow my business?

Recommendation:  Upgrading my 6kg to a 15kg machine is the perfect solution.  I currently only have 22 hours per month for selling my coffee.  With a 15kg machine, I can increase that up to 101 hours!  Alternatively, I can employ a roasting operator who can work 7 hours per day on the machine, leaving me with my full 154 hours per month to sell and grow the business.  But this operator would increase my expenses with another $3000.  So, I’d need to sell more…?

Scott Rao, coffee consultant and author, also emphasises the importance of looking towards the future when considering the capacity of your coffee roaster -- you need to know how much coffee you anticipate to roast every week for the next two years. Scott explains the crucial marker is the weekly amount of coffee you plan to roast at a point two years from the day you purchase your new coffee roaster. Scott’s recommendation is to buy a roaster size big enough to roast that amount of coffee in no more than 25 hours (

The magical art of roasting coffee

I trust that these calculations have sparked your interest and have made you more aware of the variables you need to consider when deciding on a roaster size.  We all have our own unique set of circumstances driven by our own budget and our own business plan. I have made several assumptions in my calculations which may well differ from one situation to another. I am therefore inviting you to contact me for a one-on-one consultation about your specific coffee roasting needs (

All of the best in coffee.


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This Subscription Coffee Offer from Kauai will blow your mind!

Thursday, 14 January, 2021

When the below Press Release from Kauai made its way to our inbox, we did a double-take at the crazy info it contained. But you can believe it because it is true! And if you have a Kauai near you and you're needing a bit more coffee than usual to get you through January, then you're about to feel real lucky. 

Kauai uses an organic espresso blend that is roasted and blended in South Africa exclusively for them. A blend of three 100% Arabica organic coffees to be precise:

  • Honduras - Organic SHB EP (Fully Washed) 
  • Colombia - Organic Excelso (Fully Washed)
  • Uganda - Sipi Falls Organic AA (Fully washed) 

Tasting notes:

  • As an espresso: Smooth yet full body, notes of stone fruit, warm spice. A mellow acidity.
  • As a cappuccino: Notes of caramel sweetness with a milk chocolate finish, subtle light body.

Cash-strapped South Africans can enjoy their favourite coffee or smoothie through a new subscription service that can save them up to 70% while enjoying the convenience of ordering via an app for home delivery or contactless in store collection.

Healthy natural foods specialist Kauai today launched subscription offers for unlimited organic coffee for a month as well as a daily smoothie for either 15 or 30 days, available in its 150 stores nationwide.

“Innovation is a central tenet of our business, so we are thrilled to be the first restaurant group to bring this subscription service to South Africa and one of only a handful offering this type of subscription programme worldwide. We also understand that South Africans are looking for value during these tough economic times, so have designed our subscriptions to offer exceptional value on our organic coffees and smoothies,” says Dean Kowarski, CEO of Kauai’s parent company Real Foods.

The unlimited organic coffee subscription allows customers to redeem any short hot drink every two hours for 30 days (up to 240 coffees over the 30 days) for a subscription of R299. A subscription for one small daily smoothie for 15 days costs R199, while a 30-day smoothie package costs R375, all available on Kauai’s app.

How it works

The subscriptions are purchased on the Kauai app, which can be downloaded from the Apple and Android app stores. Customers receive a subscription voucher in the app, which indicates how many coffees / smoothies have been redeemed, and how many remain. Orders can be placed at any of Kauai’s 150 stores, with customers simply scanning the app to redeem their drink. Customers can also order on the app for delivery or for contactless collection in store, to help maintain social distancing. 

The launch subscriptions are available until 28 February 2021 and further subscriptions are expected to be launched soon.

Subscription benefits

Kowarski says that the novel subscription service builds on Kauai’s strengths and reputation for great dining experiences, healthy food and honest ingredients. “Customers get their favourite drink at a lower price, allowing them to enjoy the luxury of organic coffee every 2 hours or daily smoothies at significantly better value. It’s also more convenient, as they buy once, and then simply scan the app to redeem their drink at their next order,” says Kowarski.

The subscription model also makes business sense. “Subscriptions create recurring revenue by offering customers another reason to visit Kauai and build loyalty by nurturing long-term relationships with customers. We anticipate new customer acquisition to be fuelled by subscriptions,” he says.

Leading US fast casual restaurant brands like Panera Bread have also launched highly successful subscriptions, with the chain reporting 850,000 customers signing on within the first few months. Pret a Manger recently launched a similar product in the UK.

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New Year, New Dreams: Special Offer on WIKARCS

Thursday, 14 January, 2021

In clearing out our office this week, we found a sneaky box of the amazing What I Know About Running Coffee Shops (WIKARCS) by the inimitable Colin Harmon.

If you have ever considered starting your own cafe, this is considered essential reading, from the trial and error experience of the 3FE founder and owner.

Maybe 2021 is your year?

We're doing an epic special bundle, WIKARCS + Issue 34 of the The Coffee Magazine + shipping all for only R350. Now that is a deal! The books normally goes for around R500 so you really want to jump on this bandwagon while stocks last!

"Colin Harmon is a four-time Irish Barista Champion and owner of Dublin's 3fe Coffee, one of the world's most innovative and progressive speciality coffee shops. His work in coffee has extended to roasting, training and consultancy work, as well as developing coffee equipment for the speciality market and beyond.

What I Know About Running Coffee Shops is drawn from Colin's experience in building 3fe from a one man cart in a nightclub lobby to the internationally renowned business it is today. The lessons, stories and guidelines offer a unique and honest insight into the day to day realities of what many people see as their dream job."

Order yours now! Fill in the form below and you will be redirected to Payfast to make payment.

What I Know About Running Coffee Shops + The Coffee Magazine Issue 34 + shipping - all for R350:

Personal Details
* First Name
* Surname
* Cell Number

Shipping Address
* Line 1
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* City
* Province
* Country
* Postal Code

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Goodies from The Coffee Magazine Office - Giveaway Time!

Thursday, 14 January, 2021

We are really lucky coffee humans. We are always surrounded by a plethora of exciting coffees and coffee gadgets, more than two magazine publishers, and all the people in our office and friend groups, could ever get the most out of. So as we start the new year, we have done a spring clean of our office and found some items that deserve to find new homes where they will be used and loved!

The first of these is the nifty little manual home roaster from Coffee-Tech. It is so much fun to play around with! All you need is a heat source and some patience and voila! Fresh roasted coffee at home!

So if you're looking for an exciting new hobby, why not throw your name into the ring to start off your home roasting journey.

So yes, it has been used a couple of times, but that just means it is ready for action!!!

Home Roaster giveaway

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Interview: Amy Gardiner of Humble Coffee

Wednesday, 13 January, 2021

We caught up with Amy Gardiner, owner of Humble Coffee based in Durban. Amy was integral in helping us pull off the beautiful cover feature for our current Summer issue. You can find Humble at 21a Churchill Road, Durban or give them a follow on Instagram to keep up to date with their news. All the beautiful pics below are courtesy of their profile.

Your current HQ in Churchill Place, has been a roaring success, and has become a coffee destination worth travelling for, has this journey been anything like what you imagined?

Not at all! When I found the space on Churchill Road I was purely thinking coffee roasters, training and espresso bar with some informal snacks and bagels. I really could not prepare myself for what it has turned into! I had been roasting on my own for 2 years purely for wholesale with some small retail business. I had come to realise that although I love roasting coffee, it can be a very lonely profession especially when you don’t have a staff team. To then suddenly have this space full of people, coffee, music, food it re-energised me. I came to the realisation that I need spaces like this to motivate me in my own business and I’m so happy to watch it grow and evolve.

What are your future plans for the space?

At this point, it’s a little daunting to think about the future as we’re living in such crazy times! I do have plans to extend the space by around 25 squares, focusing more on coworking. A lot of people enjoy working from Humble and I think it’s important we create spaces with this in mind, as working remotely becomes the new normal. In 2020 we hosted a couple of evening pop up events and I would love to do more of this. We’re so lucky to have lots of space and there are so many amazing creative minds in Durban that can put it to good use.  

Tell us about your all women squad please!

They’re amazing, my rock and I’m so thankful they put up with my crazy Scottish ways! We have a laugh which is so important, hospitality can be exhausting. Customers also feed off positive energy which really affects the space as a whole. 

I love how diverse our team is at the moment, from law graduates, artists to small business owners we have it all. All individual team members, Nomfundo, Casca, Rachel, Nolwazi & Sam, have their own focus separate to Humble, which is really important. 

What would your advice be to anyone with dreams of opening a coffee space?

I think, like all coffee shop owners I get asked a lot about this hot topic! I was lucky to work in the industry for a long time prior to opening my own space which I think was very helpful. You need to experience the ups and downs of this industry to see if it’s for you. It is totally possible to open a coffee shop with little experience, but it’s a lot easier If you’ve worked in a similar space before. 

If you do decide to take the plunge and open a coffee space, focus on community and a good quality, sustainable offering. You’re nothing without a strong community behind you and people truly appreciate a well thought out range of products encompassing traceability. 

What is your favourite drink and food item on the menu right now?

Drink: The Elderflower Coffee Fizz is an absolute gem, especially when trying to do life through 110% humidity. Elderflower syrup, batch brew (we usually have naturals on batch which bring out a lovely sweetness), sparkling water and a lemon wedge over ice. 

Food: The Hummus toast is a winner. 

Sourdough, avo, hummus topped with locally made feta, nut sprinkle and locally grown microgreens. What’s not to love?!

What is your favourite coffee at the roastery right now?

It’s got to be our 2020 Festive coffee, Finca La Hermosa by Max Pérez. This Guatemalan coffee was actually one of the coffees we included in the Issue 34 feature and when I cupped It I knew I had to get more! It has such beautiful floral aromas with low acidity. We get notes of caramelised nectarine & fudge with a vanilla sweetness. There’s still a few bags left at the shop. 

You sample roasted the coffees for the cover feature of Issue 34, can you tell us about the experience and about your highlights of the process?

I had just got my hands on a new sample roaster so was excited to put it through its paces! I did some planning of what I wanted to achieve in terms of flavour. As this was going to be a very visual article I knew I wanted to accentuate the coffees brightness while highlighting their individual flavour profiles.  It’s always a little nerve-racking as you only get a couple of chances to achieve this as samples are usually 200g and under. I was happy with the outcome and we had a lot of fun cupping and visualising the flavours with the various props and colours. 

Apart from your own space that you’ve lovingly created, what is your favourite cafe (anywhere in the world)?

Ahh too many choices! 

I’m going to have to go with Steampunk Coffee in North Berwick, Scotland. 

It’s a 30-minute train ride from Edinburgh (My hometown). I am in love with this quaint little seaside town and nothing completes an icy walk on the beach without a trip to Steampunk for a tasty cortado and a bowl of soup to warm up. The coffee roaster is displayed among the hustle and bustle and the café is packed with comfy couches and cosy corners. There is always a cute dog to look at. They source traceable top-quality coffee and always have such an amazing selection of beans on. 

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The Champ's Cortado: Freeze Distilled Milk Deliciousness

Wednesday, 9 December, 2020

So if you keep your eye on World Barista Championship (WBC) trends, you will have noticed that over the last few years, the milk used on stage is a little bit different than your average. Realistically we know that most of you are rolling your eyes at us right now, because only a tiny percentage of the people reading this keep their eye on WBC trends. But that's what we're here for! To give you all the latest coffee geekery in user friendly ways!

So, the trend in milk has been to use Freeze Distilled Milk for the milk beverage round to enhance sweetness in the coffees used. How does the milk do this? Well Freeze Distilled Milk is the process of freezing milk and then letting it slowly thaw over another container. This is because, the solids in the milk (all the sweet stuff) thaw first, leaving you with a rich milk concentrate where most of the water in the milk is removed.

Ok so that sounds like quite a lot of effort, but that's why we have coffee professionals in our lives! The good people at Thando Coffee Company are bringing a little WBC magic to everyday coffee drinking life by offering The Champs Cortado, a freeze-distilled milk cortado. You can go check it out in Randburg. It just adds a level of indulgence to your cup, making it a pretty phenomenal experience. Works well as a cortado too, because it is very rich, so a shorter cup is perfect!

Thando Coffee Company. The Club House Centre, Malibongwe Dr, Randburg, 2194

David, The Champ, made our cortados! They were delicious!

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Coffee Magazine issue #34: Summer 2021 is out now and it's beautiful!

Thursday, 10 December, 2020

The finished product shot in the place we we made the cover story happen, Humble Coffee, 21a Churchill Road, Durban. 

The new Coffee Magazine is out, just in time for the holidays, and it is jammed packed with 84 pages of coffee life just for you! 

Inside this issue, our cover story explores the beauty of coffee, as fashion and coffee collide in  a colour palette of art, thanks to the special skills of a very talented female coffee roaster and an equally talented friend in fashion. Celebrating the beauty in each unique coffee, we teamed up with Trend Forecaster Lauren Taylor and coffee roaster Amy Gardiner to bring you a feature that looks the way good coffee should make you feel! I mean...isn't that a glorious way to appreciate flavour?

We run a long form read on Rosetta Roastery , having managed to catch up with them in Cape Town and be present on the day they opened a new store in the centre of town. We get an in depth discussion going with the Founders, Rob and Jono as they celebrate their 10 year anniversary and reflect on a decade of dedication, still learning, growing and inspiring 10 years on.

We then bring you a very heartfelt story of courage and dedication as we bring you the story of one of South Africa’s best barista trainers, Khulekani Mpala as he starts his own cafe and coffee consultancy from within his wife’s hair salon after being retrenched from his job.

We are also thrilled to bring you an exclusive interview with Sasa Sestic and Aga Rojewska, two World Barista Champions, in this issue as we tackle their rise to coffee fame in the chase for WBC glory and all of the hardships and challenges it takes to become a world champion!

For the tech-heads out there we, then go deep into the inner workings of one of the most important pieces of equipment in coffee: The Coffee Grinder. Flat burrs vs conical burrs, different materials and coatings...there is so much to learn from the one and only Kyle Ramage (seriously, this is an enlightening article!). 

And... as if that's not enough, We even put together a bumper selection of coffee gifts in our Ultimate Coffee Gift Guide 2021.

Buy it from one of our amazing Cafe Distributors now!

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Breaking news! Genio launches new 3kg micro roaster.

Thursday, 10 December, 2020

Genio Roasters today announced the Genio 3 micro coffee roaster, a new 3kg coffee roaster that will redefine the micro roasting landscape. The Genio 3 is ideal for beginner or sample roasting. The roaster is extremely mobile and compact, making it easy to install and start roasting.

Genio sees their range of coffee roasters as a lifelong investment and promotes the new addition to the range to existing roasters as a back-up roaster and to occupy specialised smaller batches.

The new Genio 3.

“Times have changed and with 2020 as the back-drop, we have noticed that although people may not have the money for a large investment, they are still driven by their desire to express their individuality and differentiate their product from others” says Neil Maree, founder and owner of Genio Roasters. “Coffee enthusiasts may have their own career but at the same time they have a passion for the coffee industry and they recognise that they can supplement their income somewhat.

This is where the 3kg Genio roaster comes in. It is an affordable roaster for the small business owner and for the entrepreneur as it enables entry-to-market. The Genio 3 is the tool that can transform someone’s passion into earnings with their own unique product, with their own individual, personalised touch.”

Features of the Genio 3 include:

  • Compact design with small footprint at just over 1m²
  • Coffee beans easily loaded into the hopper
  • Same hand-crafted perfection and precision control as rest of Genio range
  • Castor wheels for easy mobility
  • Built-in chaff cyclone
  • Fully compatible with Genio ProRoast application
  • Weighs only 350kg
  • Wireless tablet with full manual and automatic profiling
  • Dual-wall ceramic coated
  • Motor with four variable speeds
  • Roasting time of 3kg batch between 11-15 minutes
  • Three year warranty

Genio 3 Technical Specifications:


1kg-3kg profile roasting
200g-1kg sample roasting


200 x 460 x 1785mm


  12.5kW gas burner (LPG/natural gas)

Air Flow

  Roasting fan: 300 m³/hr @ 1000 Pa
  Cooling fan: 300 m³/hr @ 1000 Pa


  220V 50Hz single phase


– Wireless tablet
– Full profile logging
– Full manual/automatic profiling

Profile Plotting

7 graphs in real-time
Reference profiles from database


Dual-wall ceramic coated

Roasting Principle

Convection & conduction

Roast Time

11-15 minutes


4x variable speed

The Genio 3 is already available for ordering and customers can expect the same performance, features and support that Genio Roasters is known for in the industry. For more information on the Genio 3, visit

About Genio Roasters: Genio Roasters is a vibrant engineering company that specialises in the design and manufacture of coffee roasting equipment. In 2020, Genio Roasters celebrated its 10th year of excellence in the specialty coffee industry. Their full range of coffee roasters (Genio 3, 6, 15 and 30) can be individually customised and designed to enhance the operator experience and the aesthetics of the roastery. Genio is currently represented in more than 22 countries globally.

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