Across every step of the coffee supply chain, quality and consistency are important concepts. Whether you’re a producer, a trader, a roaster, or a café owner, managing both is imperative for forging long-term relationships with your customers.

In the roastery, this is usually a process referred to as quality control, or QC for short. These typically describe procedures that monitor and maintain coffee quality, to ensure that the first bag of coffee leaving the roastery tastes as delicious as the last.

To learn more about QC processes and how roasters can streamline them, I spoke with Sandra Elisa Loofbourow, Director of Coffee Content at The Crown, Royal Coffee’s Lab & Tasting Room. Read on to find out what she said.

You might also like our article on the different types of heat used in roasting equipment.

What is quality control, and why is it important?

For the most part, quality control is as simple as its name suggests. In a coffee roastery, it means maintaining both quality and consistency to make sure each batch that is roasted meets established quality standards.

This is important for the roaster’s reputation, as customers will expect the same quality from each bag of coffee they receive.

The focus for most QC processes is simple: removing any margin for error in the roasting process to guarantee repeatability and consistency.

While automation is a good place to start in this regard, it is not always the right solution. As such, many roasters implement quality control “stopgaps” throughout their process. These are points where the quality of the coffee is reviewed, allowing any potential problems to be addressed.

How is quality control carried out in a roastery?

As part of her work at The Crown, Sandra explains that Royal’s Tasting Room has divided roaster quality control into two areas. 

“Roasted coffee quality control falls into two categories,” she says. “The first is how the coffee behaves in the roaster (i.e. how closely it matches the desired profile). The second is how it tastes once it’s roasted.”

“Ultimately, the most important thing is to identify your goals for each coffee, and make sure they were achieved by the production roast in question.”

Sandra also notes that many roasters employ technology to manage QC processes.

“Many roasting software applications include features which allow the roast operator to indicate roast goals,” she explains. “These can include development time, end temperature, total roast time, and can even include post-roast goals like end weight and colour track value. 

“If the roast fails to meet any of these, it can be automatically flagged as a ‘failed’ roast even before cupping.”

By using technology like this, and logging the results of each batch, roasters can store details such as the time, date, batch number and roast profile. When a failed roast does flag, as Sandra says, this data can be reviewed to see if there was any obvious reason for it.

This first level of quality control gives production roasters and anyone else working in quality control the chance to understand how even the slightest deviation from a set profile can change the flavour of the coffee.

The second level, as Sandra mentioned, is cupping. By cupping coffee regularly, you can train your palate and become able to identify any off flavours. These might be undesirable (such as vegetal or grassy notes) or simply an indicator that the roast is too developed (such as smoky or ashy notes).

Cupping coffee once it’s roasted can help members of the QC team discern more about the origin of a sensory issue. By evaluating the cup profile of a batch, roasters may be able to tell if the issue is with the green coffee or their roasting process, for instance.

“Don’t forget that roast goals are usually tied to flavour, too,” Sandra adds. “This coffee might need to fulfil a specific role on the menu, for instance. Maybe it needs to taste chocolatey on espresso, or perhaps it needs to be easy for wholesale accounts to dial in. Though these goals may seem less concrete, they can still be evaluated. 

“As always, quality control professionals should set clear goals before approaching the cupping table. In the case of a production cupping, this can be as simple as asking whether or not the coffee is suitable for shipping.”

At this point, Sandra notes that having QC team members with developed palates and good sensory education is key.

“There may be times when they need to spend a little more time at the cupping table analysing new potential roast profiles, batch-to-batch consistency, or even roast defects.”

The more skilled your cuppers are, she says, the more able your QC team will be to decide whether or not a coffee meets quality standards.

Sandra adds: “Like all sensory endeavours, the wider the panel, the more salient the data. While the roaster may have a clear idea of what she wants her coffee to taste like, other people’s sensory experience of the product will still provide valuable information.  

“This can range from soft feedback (quibbling over small details about roast curves and percentages) to crucial sensory information that could have been missed, whether due to human error, palate fatigue, or specific sensory blindness,” she says.

“Having the same team cup day-to-day is important for this, but make sure the room isn’t too crowded and the process is still efficient.”

How regularly should quality control procedures be carried out?

This is difficult to judge. Quality control is important, but it needs to be implemented as part of a wider system, and keep timeframes in mind. 

Think of it in terms of helping efficiency, by cutting down on the time spent rectifying problems pre-emptively through quality control.

Sandra says: “Like everything else, the frequency of QC sessions should be linked to your ability to execute them successfully. 

“However, there are some industry standards to bear in mind. Firstly, coffee should be cupped within eight and 24 hours of roasting. Secondly, every batch that gets roasted should be cupped.”

Setting a regular, routine time to cup coffee can help with this. Carrying out QC regularly might seem like a distraction from other, “more important” areas of the roastery, so doing it in small sessions on a regular basis will mean you won’t become overwhelmed. 

“Every production roast day should have a cupping scheduled for the following day,” Sandra says. “In addition, including QC as part of your production protocols can be helpful.

“Take roast samples immediately after your post-weights, and use software to flag roasts and make notes for the next day’s cupping,” she says. “Get production cuppings out of the way early in the morning so there’s time to make adjustments and, if necessary, re-roast.”  

By cupping the previous days roast before production roasting starts, those in charge of roast profiles can form a plan to roast the coffee differently.

“Meanwhile, service QC – evaluating what the roast tastes like on a specific or intended brew method – can be done less frequently as part of your quality assurance program.”

For service quality control, keep an espresso machine and filter coffee brewer somewhere in the roastery to check how the coffees work on different methods.

“There’s simply no replacement for human sensory abilities,” Sandra says. “No machine or roast curve can tell you what the coffee tastes like with the absolute certainty of your palate.”

For most coffee professionals, quality control is an enjoyable and educational way to work directly with freshly roasted coffee on a regular basis. 

Getting the right equipment & processes

When setting up a QC programme in your roastery, having the right equipment & processes helps to keep everything streamlined and efficient. 

Sandra says she has a simple “checklist” for roasters and QC teams to run through before they get started:

• Your cupping setup
  • How many cups per batch?
  • Will you use a control sample?
  • Which cupping form are you using?
  • How many people will be involved?
• Feedback
  • Where do notes get logged?
  • Who has access to them?
  • What is that information then used for?
• What happens to coffees that fail?
  • Are they recapped?
  • Reroasted?
  • Repurposed?
  • Or ground and composted?

She also says that your head roaster or head of coffee should have the final say on whether or not a coffee meets your standards. 

Coffee roasters know that quality control is important, but establishing a formal, regular, and efficient QC routine is easier said than done.

By streamlining your quality control processes, minimising workload, and using professional roasting software where possible, you can track, log, and rectify problems with a roast before they become a major issue. 

Make sure your cupping team has the right sensory knowledge to identify defects or issues, and set out a clear process to follow when something goes wrong. In the end, you’ll find this makes everything much more efficient, saving your roastery time and money.

Enjoyed this? Then try our article on switching from home to production roasting.

Perfect Daily Grind

Photo credits: Evan Gilman

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