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A Diedrich Roaster will create the same feeling and memory. Starting with the aircraft certified bolts tightened to the handcrafted steel that holds your roaster together, to the unperceivable, perfectly formed tig welds. Created by a Roaster striving to set a higher standard in coffee. Engineered to bring the best taste out of any kind of bean, using our signature infrared burners. Everything on a Diedrich Roaster is crafted to do one thing: give the operator the same experience roast to roast, year after year. Leaving our craftmanship unmatched in specialty coffee roasters.
There are Diedrich roasters operating in the market over 35 years old. They might have some chips and dings, but the roast is still consistent.
Authority to stop production
In any manufacturing company there is a delicate dance of completing parts in a timely fashion as they are needed by the next phase in production. There are nearly 1000 components that go into building a Diedrich roaster. Stopping any part of the process can shut down the entire production (depending on the part).
Even with that knowledge, at Diedrich we value the skills of our craftspeople. We empower any employee to have the authority to stop production if there is something is not perfect with the part they are building. We are highly productive, but we will never sacrifice quality!
Custom to your needs
Have you ever wondered why there aren’t a bunch of Diedrich Roasters sitting in a warehouse waiting for you to buy? It is because each installation is unique and YOUR WANTS AND NEEDS will never be compromised. We need to know details about your installation, automation level, color choices and even exhaust requirements before we start building your roaster.
We want you to put your personal touches on it. This is a large investment and we want it to be just right for you. What color do you want? Pin striping? Custom logos?
Even with the tight controls and customization options, we are very swift at making your machine. Often, we are asked to hold shipping it out because the space is not ready!
When you test drive a Diedrich, and get that satisfying thump when you close the door, you will know you want to drive this machine forever!
What Makes Diedrich Roasters Different from the Others?
– Low NOx Infra-red burners – very clean burning and over 50% more efficient than blue flame burners which dramatically reduce energy costs and provide a far cleaner roasting medium .
– Heat exchangers – provide a clean, hot air roasting medium; Diedrich Roasters do not use the contaminated, dirty burner gases as the roasting medium .
– Independent control of convective and conductive heat – precise control of roasting medium allows for maximum profile roasting capabilities .
– Solid steel tube frame – verses the stamped out sheet metal frames.
– High quality U.S. milled steel – sourced from manufactures in the U.S.A.
– Stainless steel finish – Diedrich Roasters do not use chrome or brass plating as others use.
– Hardened stress proof steel drum shaft – drum shaft will never need replacement .
– Stainless steel drum door, hopper and air control handles – not the typical chrome plating found on other roasters .
– Grade 8 nuts and bolts – grade 8 hardware is heat treated high strength steel. Bolts do not break off when removing, even after many years of use .
– Babbitt drum door bearings – not simply metal on metal causing wear
– Fafnir™ Drum Bearings – highest quality U.S. manufactured bearings.
– Stainless steel belly skin – no rusting out of the belly skin from condensation or moping of the floor .
– Stainless steel cooling bin – quality not chrome .
– Removable stainless steel cooling agitator – heavier quality construction with Polyethylene lined sweepers make cleaning easy .
– Large access doors and easily removable blower cover encourages cleaning .
– Heavy duty and hand built with America quality- the Diedrich Roasters are the most solid built machines on the market.
– High quality fit and finish – Diedrich Roasters have a powder-coast finish unlike other roasters .
– Ergonomics – the cool, exterior temperatures reduce operator fatigue; all controls are comfortably situated.
At Diedrich Roasters we understand that we have a role to play in stewardship of the environment. As the center of the supply chain of coffee we see the great efforts being done before we get the coffee and after it leaves the roaster. We endeavor to do our part in the middle!
At the farm great strides are being made in educating farmers to work with the land and not to use its resources. As you might imagine in third world countries this social, societal and economic change is slow, but going in the right direction.
In the retail stores the movement toward utilizing recycled materials in the store as well as serving in compostable materials are prevalent. Some go further than others, but on the whole the trend is to err on the side of Mother Nature over profit if you can’t get them to work together.
As a roaster manufacturer, our job is to turn the green coffee as a raw material into a finely crafted food product. In doing so we are faced with the fact that when coffee is roasted, smoke is created and fuel is consumed. We create a carbon footprint. What we try to do at Diedrich is minimize that footprint and allow our customers to roast in a way they can be proud of in both quality and environmental impact.
The design of a Diedrich roaster is no accident. We strive to give maximum control over attribute development for the person using our machines. It just so happens that this design also makes a Diedrich roaster one of the most eco-friendly on the market. We give control through two significant design differences: Infrared Burners and Heat Exchangers.
Infrared Burners are more efficient and burn natural gas more cleanly. By capturing heat in the ceramic plate of the burner, less heat is sent through the air and out the stack. When the ceramic plate heats up it glows a nice red-orange and like the sun transmits radiation waves to the drum that are not susceptible to heat loss through airflow.
Heat Exchangers consist of an abundance of steel plates that surround the drum. Any air entering the drum has to pass through these plates. The plates are retaining heat from roast to roast once again creating an operating environment that needs less gas to roast a batch of coffee. For the operator it means that you can rely on a stable air temperature going into the drum and control that heat transfer by using air controls, not gas consumption. Stability and predictability make the heat exchangers the ‘secret weapon’ of profile development.
Together, the Heat Exchangers and Infrared Burners create an environment that uses 30%+ less gas than a typical atmospheric burner for the same batch size of coffee. The result:
If you use 30% less gas, then you will have 30% less omissions!
But it is more than that. With burner efficiency you will see reductions at different levels of the types of substances leaving the building.
Toxic Gases | Emission Reduction |
---|---|
NOx | 3-4% |
CO | 40% |
CO2 | 60% |
SOx | 70% |
Aldehydes | 65% |
Zene gases | 65% |
And if that is not enough reduction for you, Diedrich Roasters have a Low NoX Catalytic Oxidizer that basically cleans so much that only hot air leaves the building.
To say we are eco-friendly is only telling half the story: We are eco-friendly because we designed the machine to give total control of the roaster to the person operating it. The two thing are inextricably intertwined!
When you think about coffee, what comes to your mind?
You might just think about the barista, with their finely combed beard and awfully tight suspenders, handing you your favorite white chocolate mocha or salted caramel latte over the bar counter. “Thanks,” you say while taking a sip. You wonder how all the flavors and textures in the cup — the rich espresso, the frothy milk, and all the other sweet additions — strike the perfect balance in your mouth.
If you’re a little more curious, you might know a thing or two about actually making the beverage. When you think about coffee, you might imagine dialing in the perfect grind size, cautiously extracting just the right volume of espresso, artfully pouring water with just the right motions, or steaming milk with just the right consistency.
And for most people, baristas and coffee professionals included, the thinking stops there.
It’s true. Café and home baristas alike spend an inordinate amount of time perfecting their extraction techniques and mastering several different brewing methods in the hopes of achieving an amazing cup of coffee. But they often forget that the most fundamental part of any brewing method, and the thing that most affects the taste and quality of the coffee itself, is the process of roasting.
So why does the roasting process matter so much? And for the average consumer who just wants a good cup o’ joe in the morning, why should you care?
You see, the “story” of coffee, like tea or wine, is the tale of a beautiful and incredibly complex phenomenon. Many people think that coffee roasting simply means taking some beans and applying some heat until they turn a certain shade of brown or develop a certain number of cracks. The reality, though, is that how the heat is applied affects the evolutionary path of its chemistry and has a tremendous effect on flavor.
What’s so complex about the beans themselves? Unroasted (“green”) beans come with a lot of variation. Their qualities depend on when and where they were picked, at what elevation they were grown, how they have been washed, how big and heavy they are, how much moisture they contain, and so much more. To put it simply: No two batches are quite the same.
The problem is that, while coffee comes with a lot of variation, most roasting machines don’t. This makes it difficult for many roasters to achieve consistently high-quality results, especially if they’re only making small batches.
Diedrich IR-series roasters solve this problem by combining the most efficient technology with several types of heat processes, allowing the roast-master to adjust them independently of each other. The result? Perfectly roasted coffee, customized for each specific batch, every time.
How does Diedrich IR technology work?
To demonstrate how exactly Diedrich IR roasters achieve this remarkable feat, we need to get a little nerdy and talk about science. The most important variables for any kind of roasting are the type of roaster used, the temperature of the beans, and the duration of the roasting process. Today, we’re going to focus specifically on heat.
The goal of heating anything is to transfer heat from a warm object to a cooler one. This can happen in three different ways: convection, conduction, and radiant.
Convective heat uses hot air that circulates between warm and cool areas. Think about an electric oven or running water over frozen food. The warmer surrounding air replaces the cool air nearest to the object. In coffee roasting, however, this has a massive downside. The surrounding air is usually “dirty,” infusing the beans with nitric oxide, carbon monoxide, carbon dioxide, and other gases that can make your coffee taste impure. Despite this fact, most drum roasters still utilize this method.
Conductive heat uses direct contact with hot surfaces. Grills and electric stove burners work via conductive heat. If roasters are only using conductive heat, the resulting roast tends to be uneven. Think about roasting beans in a skillet but on a much larger scale. It’s virtually impossible to guarantee that the beans will have equal contact with the drum surface.
Radiant heat uses the emission of light and heat waves to penetrate a surface. This happens every day when sunlight heats the earth’s atmosphere or when you warm your hands over a fire. Radiant heat doesn’t actually require any matter to transfer energy. Because of that, very little energy is lost in the process, making it the most efficient of the three.
The problem with most roasters is that they are unstable. In the case of fluid-bed roasters, which levitate coffee beans with hot gas, the velocity of air can’t be adjusted, among other problems. But even in the more popular drum roasters, which lift and drop the beans through hot air, adjustments to one variable will cause huge fluctuations in the others.
Most drum roasters are “atmospheric,” meaning that they utilize a blue flame and the surrounding air to control temperature and velocity. Diedrich IR roasters fixes the instability problem inherent to atmospheric roasters by utilizing infrared technology. Infrared roasters provide clean and even roasts with radiant heat.
By combining all of the methods mentioned above in their gas burners and heat exchangers, the Diedrich IR-series roasters allow for the controllable volume of clean air that isn’t prone to the temperature fluctuations of atmospheric roasters. Diedrich is the only roaster to optimize all three types of heat and give the roast-master independent control of each.
Clean air is drawn through the heat exchangers, which uses convection. Even after the flame is turned off, these exchangers provide stable air temperature for an impressive 4-6 minutes. The carbon steel drum first emits radiant heat directly proportional to the heat of the metal and secondly employs conductive heat via direct contact with the coffee beans.
The roast-master can vary the air velocity, energy in the drum, and temperature during different stages of the roasting process and according to the needs of each batch. Because of this, Diedrich roasters can roast a four-ounce batch with the same precision as a full batch.
And that’s all there is to Diedrich’s secret of success. It’s not just the about the machines. It’s Diedrich’s commitment to constantly innovating and giving you the best coffee possible. From process to product, Diedrich knows coffee like no one else.
You love coffee, we love coffee. We’re after one common goal: crafting the perfect cup. The physics of roasting on a Diedrich with our infrared burners and heat exchanger technology give you unsurpassed control over your roast.
LEARN MOREWhen you purchase a Diedrich you also have available a wealth of coffee roasting knowledge from our 30 years of experience. From education to service, we enable you to achieve the perfect roast every time.
LEARN MORERoasting on a Diedrich is better for the earth and your coffee. Our infrared burners reduce noxious gas emissions. Efficient roaster design reduces operating costs. This cleaner roasting process allows you to bring out the true quality of the bean.
LEARN MOREUse this calculator to estimate what you will make per year based on these assumptions
"When Onyx Coffee Lab was first started, we wanted two main things in a coffee roaster. We desired a roaster that produced an extremely clean cup of coffee and one that allowed us to consistently roast the same batch time and time again. And with Diedrich Roasters, we got both!"
"Working with Diedrich has been a pleasure from day one. Their customer service team is highly informative and helped us figure out what roaster would be the best fit for our operation. The craftsmanship and quality is uncompromisable. This is a diligent team with an eye for detail and a love for what they do. From taking their workshops and testing their roasters, we are confident in choosing a Diedrich."
"The machine just showed up. Those guys in shipping do a heck of a job crating things up; I think I can reuse it as a garden shed. Thanks for everything"
"Couldn’t ask for a better machine. Seven years and 100,000 pounds roasted for our clients."