Random Musings of a Coffee Technologist

When roasting coffee, how the coffee is roasted has a large effect on the final flavor of the coffee. Every lot of coffee requires its own unique roast profile to bring out the desired character of that coffee. Even when roasting the same mark of coffee from the same farm to get the same flavor from one season to the next may require changes to how that coffee is roasted. In order to achieve the desired results, there must be a procedure for determining the desired roast profile. The following procedure works for me. It may work for you, but it won’t work for everybody. To use this procedure, you need a coffee roaster that is both controllable and provides good bean temperature measurements at batch sizes small enough that you won’t mind wasting a few batches figuring a out a profile. The roaster should also have a well placed and sufficiently large sample trowel to extract a usable sample of coffee quickly during the roast.

Start by roasting the coffee in several ways. The easiest way to do this is to roast a small batch of coffee and pull several samples from that batch. These samples should cover a range from too light through too dark with as many samples in between as possible. What degree of roast is too light or dark is a judgement call based on what you’re looking for in that coffee (perhaps informed by an earlier sample evaluation) and personal or customer preferences. It may be useful to do this with a few small batches to explore the effect of different airflow manipulation patterns or different amounts of time in important regions of the roast. If you’re not in a hurry to figure out the roast profile and already understand how these changes influence the flavor of the coffee, start with one batch and use the evaluation of the first set of samples to guide further batches if required.

When roasting these batches, it is important to remember that the final goal is a reproducible roast profile. This means that you need to understand the limits of your roaster with larger batch sizes to avoid designing a profile that is impossible to duplicate with a larger batch. It also means that it is important to keep a record of the roast profile and the time and bean temperature at which each sample was pulled. Using some sort of automated data logging such as Typica (which was designed with this sort of use in mind) is helpful but not required. If you opt for manual data logging and are uncoordinated, get another person to record the data as you roast and pull samples.

After pulling these samples, the coffee needs to be cooled. Due to the small amount of coffee in each sample, little is needed to cool the sample in an amount of time similar to the cooling time for a full batch. I collect my samples in small glass cups and shake these in such a way as to toss the coffee into the surrounding cooler air.

The samples should rest at least four hours before they are evaluated. Shorter resting times can be used with practice, but the flavor of these samples will not match as well with how anybody else will drink the coffee. I have not determined an upper limit on the amount of resting time, but letting the samples rest overnight is fine as long as the samples are kept free of environmental contamination.

Once the roasted samples have rested, it is time to cup them. The procedure is similar to that used to evaluate green coffees, but there are some important differences. The amount of coffee available from each sample is much smaller. You’ll only have one cup from each sample with a small amount left over. You’ll also often be working with a large number of distinct samples which makes most cupping forms unwieldy. I use 12 grams of coffee ground to setting 5 on a freshly calibrated Ditting grinder in ceramic cups with a capacity of 8 fluid ounces. Don’t trust those numbers. Run your own experiments to figure out what cupping procedure works best for you.

You don’t need to rank these samples. Remember that the goal is to determine what roast profile you want to use. You will be rejecting most of the samples very quickly and no observations need be noted for those samples that cannot be used. Hopefully, you find a sample that matches what you want out of that coffee. If you do, you can move on to the next step. Otherwise, you’ll need to roast another set of samples using your observations and experience to determine what changes to the roast profile are most likely to produce better results. You may want to write a brief description of the sample you’ve chosen. If you find a sample that you have no immediate need for but may find useful later (for example, in blending), it can also be useful to make a note of that, but standard evaluation forms are a poor fit at this point.

Once the desired roast profile is found, a batch of coffee should be roasted to match that profile. This is done to ensure that the chosen roast profile can be matched. An evaluation of this coffee will further verify that this is really the roast profile you want. I’ll usually prepare a drip pot of the coffee as that is how most people will be enjoying it. This evaluation can be used to produce a marketing description of the coffee and to set the quality assurance parameters future batches will be judged against.

A popular model for coffee roasters has been to be the one stop shop for coffee retailers. Someone starting a new shop isn’t looking for a coffee roaster just to supply coffee, but also to provide equipment, training, and other assorted supplies needed by the typical coffee shop. Not all roasters do this, but most retailers seem to prefer working with one company that can provide several related services rather than a few companies that specialize in a single one. There are pros and cons for both the roaster and the retailer side of this, but today I’d like to just consider the issue of roaster provided training.

From a roaster’s perspective it would seem to make a lot of sense to offer training to customers, especially those customers who are just starting out. Even the best coffee can be ruined by poor preparation and if a roaster’s coffee is going out to a large number of shops that don’t have a well trained staff, people might think coffee from that roaster is no good. While roaster provided training is no substitute for a proper training program internal to the retailer, it should at least be possible to pass along the basics of proper coffee preparation and help retailers avoid some common mistakes. Right? I’m not so sure about that.

Several years ago, a new business opened near where I lived. It wasn’t a coffee shop, but there was space set aside for one as soon as the financing could be arranged. I spoke with the manager of the shop about it and it turned out that this coffee shop was her pet project for the store. She was going to do everything right. She wasn’t planning to buy coffee from me, but already had another supplier picked out. The roaster they had decided to go with had an excellent equipment program and while I’ve never gone through their training, they certainly seemed to know what they were doing at their own shops and did well in barista competitions. Their coffee was also almost as good as mine. I figured this new shop was in good hands and I looked forward to having a decent coffee place nearby that I could go to in the evening.

About half a year after this shop opened, the coffee area was finally ready for customers. They had good coffee, good equipment, and watching the mannerisms of the manager who was acting as the barista on the night I and a coworker went there, they had obviously taken the training. There was a band playing in the corner and the ambiance of the shop was great. I was looking forward to having a good time and placed my usual first visit to a new shop order, a single espresso and a small coffee. I watched as the manager ground the coffee, dosed the fresh grounds into the portafilter, tamped, and pulled in a mere 10 seconds a four ounce espresso. As I drank my sad excuse for an espresso and the only slightly larger small coffee (which was not as good as it should have been but was at least tolerable), I kept my eye on the bar and noticed that the preparation was very inconsistent, but every attempt was served because the manager/barista was doing everything right. Before we left, my coworker introduced himself as someone from my shop and complimented the decoration of the shop. She smiled and said, “I’ll have to visit your shop some time… if it’s still open.” My coworker and I joked about that after we left, but I was willing to keep an open mind and try it again once they’d had more time to practice. I never got the chance. About two weeks after the coffee shop was opened, the owner of the store paid a visit to see how things were going. I can only imagine what abomination he was served which was so bad that he ordered the coffee shop portion of the business closed immediately. They made some attempts to get another company to open a coffee shop in the space, but were unwilling to make some changes that would have been needed to make that viable so the space was left shut down and empty.

I know that this is an extreme example. Obviously the training hadn’t done any good in this case, but would things have gone better had training not been available? Is it possible that this training was, in fact, harmful? That training had been taken shows that this person had at one point realized that she didn’t know anything about coffee. If training had not been available so easily or so cheaply, perhaps she would have undertaken her own studies. She might have read a couple books on the topic (good ones were at the time available in the local public library), gone to other shops to learn what the drinks on her menu looked and tasted like elsewhere, and perhaps she would have even practiced before opening a coffee shop and learned how to make delicious coffee drinks. Instead, she learned the proper techniques, was doing everything right, and was shut down because the drinks she served were bad.

One of the things I do at work is develop a program called Typica. This is a simple program for making it easier to collect the various sorts of records that are generated as part of running a coffee roasting operation and for making it easier to use those records to reduce roasting errors and make better decisions based on roasting, cupping, and inventory records.

Since there was a direct financial benefit to having better tools for working with this sort of data, I’ve never had to think about making Typica commercially viable on its own. That’s great for me as there’s a reason I went into the coffee business instead of the software business. When I think programs that I write are good enough to be useful to others, I can just release them under the highly liberal MIT license and let other firms do as they please with it and I don’t need to know about it.

The down side of this is that there’s no marketing budget. It could be the greatest program there is for roasters (indeed, it is), but if nobody ever hears about it, nobody is going to use it. This is a pretty niche application and a lot of roasters are perfectly content to stick with a pen and a stack of notebooks or some abomination in Excel.

About a month ago I got an email informing me of the Qt Ambassador program. Typica makes extensive use of Qt and there aren’t many programs like it, so I figured I might have a good shot at getting Typica accepted there. Nokia gets to say, “Hey, look at the cool stuff Wilson’s Coffee & Tea is doing with Qt,” and I don’t have any reservations recommending Qt for application development. It cuts down my development time considerably and very little effort is required to get Typica working on all major platforms.

I filled out the application and didn’t hear anything about it until today. I had assumed that Typica had simply been rejected without notice, but today I got an email saying, “Congratulations! You have been accepted into the Qt Ambassador Program.” The next step was to check over the application and attach four screenshots of the program. There is still the possibility that the application could be rejected, but I remain optimistic.

While updating the application, I noticed that Nokia plans to allow multiple applications from the same account, so perhaps once it’s released, I might also be able to get Catimor featured.

This was in reply to My thoughts on Multi-Roaster shops.

Thanks for the interesting read. Before my shop started roasting in 2000, we had been purchasing coffees from multiple roasters for several years and I doubt we were the only ones doing so at the time. The model is likely much older than you suggest. The difference was that while we would provide an honest answer if someone asked which roasting firm produced a given coffee, we considered the coffee ours and marketed it as such. You’ve covered the main advantage of this in the asterisked pro, but it also meant that when we started to roast our own, our brand had already been developed, making the transition much easier.

The cons listed are rather interesting. The first one listed, it can be interesting to examine from the retailer’s perspective as well. When adding additional suppliers, there is more work involved in managing inventory and it can be more difficult to meet minimum orders. These retailers who are only getting 5–10 pounds per week from several suppliers don’t sound like they’re moving product fast enough and are likely running into supply issues that will hurt their reputation with their customers in the long run.

The training issue I fail to see as legitimate. Perhaps this is because at the time I was under this model, our internally developed training (based on books, SCAA resources, and a fair amount of experimentation on our part) was far superior to anything our suppliers were offering at the time. Now that there are more training resources available, I still see shops that have obviously gone through training provided by a roaster (they all have some quirks so it’s easy to see where the training was done) yet make basic mistakes that ongoing internal training programs could correct.

The others are things we were able to avoid through private labeling. Other firms were roasting, but it was our brand. Advertising a competing brand wasn’t something we really wanted to do. There are trade offs with that decision and that really comes down to a question of what kind of business you intend to run.