The Development History of Coffee Bean Dryer: pan, Roller, Commercial Bean Dryer, Hot Air Bean Dryer

The era of pan baking

Coffee has a long history. The first people to roast coffee beans into drinks can be traced back to Central Africa and the Middle East hundreds of years ago, and then the Ottoman Turkish Empire and European colonists brought coffee to the world.

The earliest bean roasting tools were thin, perforated pans that roasted directly over a high fire, and coffee bakers used spoons to turn the beans and make sure the roasting was uniform.

Only a small amount of the whole pot of coffee beans will be roasted at the same time, which means that the roaster who turns the coffee beans needs to be very focused throughout the roasting process.

The process produces a lot of smoke and silver dust, and, as expected, the roasted coffee is uneven and uncontrolled.

Due to the chaotic and inconsistent results of the stir-frying process, it is conceivable that these coffee lovers will begin to look for new ways to bake coffee beans.

The era of drum bean dryer

According to relevant historical records, the drum dryer first originated in Cairo, Egypt, in the 17th century. Such equipment allows beans to be placed in a semi-enclosed space, so that the heat in the drum can be released, and the handle of the drum can be rotated. so that the drum dryer can be moved more evenly when it comes into contact with the fire.

This design will also reduce the amount of smoke emitted, making coffee bakers more comfortable. After that, some adjustments have been made to the drum bean dryer, but its central concept remains unchanged. With the development of colonialism, drum bean dryers were designed all over Europe and America.

Development of Commercial Bean Dryer

Coffee roasting is also affected by industrialization. In the 19th century, although many people continued to bake their own coffee at home, commercial bean dryers were patented in the United States and Europe.

Many early commercial bean dryers simply put huge cylinders on top of the heat source, but before the introduction of natural gas as a source of energy in cities, the heat source was always wood or coal, and the roasted coffee was full of smoke, so, when natural gas is available, it quickly becomes the preferred heat source for this kind of bean dryer.

Richard Evans patented the first large coffee bean roaster in England in 1824. According to the book The Curious Barista's Guide to Coffee, it allows users to turn the entire cylinder upside down to expel roasted beans, and is equipped with a "sampler" to take out some of the coffee beans during roasting to confirm their roasting status.

The book also states that James Carter applied for a patent for a "pull-out" bean dryer in Boston in 1846. This is an iron cylinder fixed in the boiler. When baked, you must pull the whole drum out of the boiler and open the door so that the roasted coffee can be poured on the floor or in a tray to cool, but this is an inefficient and dangerous method.

In 1864, Jabez Burns obtained a patent for a commercial coffee roaster in the United States. Burns is designed to cover a closed cylinder with a brick structure, it has an opening mechanism to empty the coffee beans without removing the cylinder from the flame, and the double helix design inside the cylinder can evenly divide the coffee beans, these innovations make the baking procedure more consistent and safer.

Burns's company later added a cooling tray to the front of the bean dryer and installed a fan beneath it to blow cold air into the coffee beans, laying the foundation for modern coffee dryers.

In 1868, Alexius van Gulpen founded a company in Germany with Theodor von Gimborn and Johann Heinrich Lensing, which later developed into what is now Probat. They patented the fast coffee bean roaster in 1880, which the company said was important for the future development of drum bean roasters.

The influence of Electric Power on Bean Dryer

With the increasing popularity of electric power at the beginning of the 20th century, the coffee roasting industry has also changed.

Electric drive means that baking becomes less labor-intensive, and because electroheating is more predictable than open fire, the baking results are more consistent and less dangerous. For the first time, the bean dryer can control the ability of coffee beans to be exposed to heat with a certain precision, and has a better ability to copy.

Hot air bean baking machine

Today, the drum bean dryer based on 19th century patent design is still the first choice for many people. But in the 1970s, semi-hot air or all-hot air bean dryers appeared on the market.

In a hot air bean dryer, the machine forces hot air through the sieve beneath the coffee beans, strong enough to blow up the coffee beans and transfer heat to them as they tumble. American chemical engineer Michael Sivetz applied for a patent for the design in 1976.

At that time, many bean bakers were less likely to choose hot air bakers because they could not provide the same baking quality, which was due to the fact that heat transfer only used convection rather than a combination of convection, conduction and radiation generated by drum baking machines.

The application of new technology

A better understanding of the chemical composition of coffee and what changes will occur in this process will contribute to the development of modern coffee roasting. The bean baking machine can better measure the factors and analyze the reasons for the success of baking. With the help of digital temperature and profile software and other technologies, baked beans can be more efficient and consistent than ever before.

But these innovations are still based on core inventions from more than a century ago. The bonuses of modern technology can help us better control baking, but they are essentially fine-tuning 19th-century drum bean roasters.

Over the past few decades, due to the efforts of many people and companies, bean baking equipment has been developed and improved. Without some counter-experiments, we will not have all kinds of delicious coffee that we like now.

In the future, we look forward to integrating more technologies into coffee roasting technology, and there may be exciting developments!