A Day in the Life of a Coffee Bean Roaster|What Does a Coffee Roaster Do?

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Yes, coffee bean roasters are indeed like boiler workers - buried in their work all day, firing and maintaining boilers. However, I prefer to call them Taoists - oblivious to worldly matters, focused solely on refining their craft.

Today, let's take a look at how our roasters serve everyone.

Normally, you'll see roasters silently staring at the roaster. Many people ask: What are they looking at?

They maintain constant concentration - time, temperature, bean color, bean shape, smelling aromas, listening to sounds, recording roast curves, adjusting heat and airflow, determining when to drop the beans... For a ten-minute batch of coffee beans, roasters must engage all five senses throughout the entire process, all for the sake of delivering a good cup of coffee to the customer.

In addition to daily production, they must frequently fine-tune roast curves and conduct cupping to ensure quality. After all, coffee is an agricultural product that ultimately "depends on nature's bounty." Given the anticipated fluctuations in raw material quality, different batches of the same bean must be compared through roasting. Moreover, we haven't yet achieved direct purchase from origin, which introduces many variables in the intermediate stages. Therefore, regular adjustments are essential.

Green Bean Evaluation

Beyond daily roasting and cupping, roasters must perform a crucial task - green bean evaluation. It must be emphasized that coffee isn't ready to sell simply by being roasted. Before us lies the diligent labor of producers; after us awaits the eager anticipation of customers. Therefore, green beans are particularly important. Roasters must not only showcase the best flavors of coffee but also have comprehensive understanding of each batch of incoming green beans.

1 | Comparative Analysis

For small-batch green bean purchases, we should conduct comparative roasting of old versus new stock, using identical roasting methods, then cup to determine whether flavor characteristics remain consistent. If differences exist, roasting adjustments must be made to strive for flavor consistency. However, if a particular coffee cannot maintain its previous quality for various reasons (especially micro-lots or small estate coffees), then the next step is necessary.

2 | Bean Sourcing

Large green bean merchants can travel to producing regions and estates to source beans, but as end-users, our sourcing approach is relatively "low-cost" - by understanding the coffee's origin, altitude, soil, cultivation and post-processing methods, we purchase beans with similar characteristics and flavors for comparative roasting to find suitable substitutes. This process is another battle between alchemists and dishwashers (omitting ten thousand words here).

3 | Bulk Inspection

When several large bags of coffee beans arrive, roasters must inspect them. First is visual inspection - checking for uniform size, consistent color (moisture content), sampling for defect rates, and so on.

As shown in the image above, although these are the same beans, their moisture content varies significantly, clearly indicating mixed-grade sales. When such green bean conditions are discovered, a return warning should be issued - excessive moisture content differences will cause uneven roasting and无法保证品质 - both green bean merchants and end-users should be responsible for industry integrity and stable, prosperous development.

Additionally, some mixed bean situations involve blending normal quality beans with lower-grade ones. We must conduct sample roasting and cannot be careless!

Sometimes to conceal the truth, normal quality beans may be stacked on top while poorer beans are mixed below. We need to conduct "in-depth" inspection - taking 1/3 of green beans from upper, middle, and lower layers respectively for mixed roasting, then observing whether bean shape and color are consistent.

There are some exceptions, such as African Ethiopian coffees graded by green bean defect rates, where bean sizes may vary due to the numerous varieties, which is also the source of their rich flavors. The roasted beans may show some degree of color unevenness, but as long as it's not significantly different (for example, some developing well while others are wrinkled or have cracked center lines turning black), and cupping confirms correct flavors, this is normal. Roasters must clearly understand the grading systems of producing regions and ultimately make objective analyses through roasting and cupping.

Through the discerning evaluation and sensory adjustment by roasters and baristas, a cup of specialty coffee finally presents itself before everyone.

The above represents the meaningful daily routine of our boiler workers.

Important Notice :

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