IKAWA sample roasters have been a staple of coffee professionals starting with their introduction in 2013. In the same year, IKAWA launched a Kickstarter campaign for its home roaster. The IKAWA name and its elegant design suggest that it's a Japanese product. But the company is headquartered in Britain, where the roasters are assembled. The IKAWA name is actually derived from the name for coffee in Burundi, one of the coffee growing countries where Andrew Stordy, the company's founder, grew up.

In October 2021, IKAWA announced a 100g version of the Home roaster, whose former capacity was 50g. It also upgraded its app on the Apple platform. IKAWA's introduction of its latest Home version is the occasion for this review.

IKAWA pioneered the app-driven, portable sample roaster. Sample roasting is a longstanding practice in the coffee industry. Traditionally, sample roasting was a rudimentary process of loading beans into a pre-heated, rotating drum. By applying consistent procedures, professionals would create a light roast for the cupping table that revealed any flaws in the coffee and showed its flavor potential. Later, professionals started using very small roasters that were capable of creating profiled roasts. A light cupping sample roast might be one option. Another option would be to experiment with roasting profiles to feature that coffee at its best. Such profiles would then be adopted to much larger production roasters.


Photo by IKAWA Home

With an app-driven small roaster like the IKAWA, the same greens could be roasted the same way regardless of location. Professional roasters could receive a sample of greens and roast them to their preferred profiles. To support quality coffee production at the source, IKAWA donated some of its roasters to coffee farmers, so they could taste how consumers would experience their crop. Samples could now be distributed as greens to coffee roasting companies to be assessed with their preferred profiles. Companies with multiple roasting locations could share recipes to demonstrate preferred profiles.

Adapting its Technology for Home Use

With the IKAWA Home Roasting System, the technologies developed for professionals were adapted for home use. The IKAWA Home System is not a profiling sample roaster. Some of its components are different. It has only one sensor and different software. But it offers the advantages of an app-driven roaster. For its Home customers, IKAWA packages high quality green coffees and provides recipes for automated roasting. This allows new users without prior roasting experience to start tasting the subtle flavors of a fine coffee. They can also roast similar coffees to those curated by IKAWA. And for any coffee, they can adjust the roast to their taste with an easily used interface that doesn't assume roasting expertise.

With an IKAWA Home Roasting System, coffee lovers can now produce fresh-roasted coffee for the price of buying quality roasted beans. And by planning a few days ahead, they can always have fresh-roasted coffee available. After using the greens starter package that comes with the roaster, owners can buy individual coffees on the website. With the Home system app, IKAWA offers access to a Graph Editor module to the software via a monthly subscription of $5.99 U.S./£4.99. In the EU and UK, the company offers a different type of subscription that provides a discount on the roaster and credits that owners can apply to new coffee purchases, accessories and shipping. This lowers the initial cost of the roaster but makes it more expensive over a two year contract. Please see their site for details.

Each unique coffee comes with pre-programmed roasting recipes to eliminate much trial and error. Those recipes can be adjusted for the degree of roast (from light to dark) and development time (low, medium, high). IKAWA Home typically provides a recipe or two for filter brewing and one for espresso. This offers a general interface for a beginner but is a different frame of reference than what's familar to an experienced roaster. IKAWA's home package is also priced much lower than its professional sample roasters, which have features that would be harder to master for a new user.


Photo by IKAWA Home

For those who are interested in a "newbie" point of view on the IKAWA Home roaster, watch the video below from Martin Keen and Dan Kehn. Both of them have nearly zero roasting experience and yet came away pleasantly surprised:
Of course, this is Home-Barista.com, where we have many dedicated coffee hobbyists and our most active members like to take a deeper dive into coffee preparation. They want to fine-tune the process to suit their preferences. A few eventually become coffee professionals, and these forums are their sandbox for experimentation. So, this review is also aimed at our experienced members. Some of them are early adopters of the latest IKAWA Home roaster, and their threads have helped me prepare this review.

My initial posts will introduce you to the IKAWA Home Roasting System for anyone who's considering buying it. I start with basic workflow and the supplied app that includes the ability to adjust roasts without the add-on subscription that adds a Graph Editor. This is followed by more fine-tuning with the app's Graph Editor and the use of that feature to simulate some settings in the Pro app. Experienced roasters can skip my posts for beginners on how to evaluate coffees and how to approach tasting coffee flavors. After covering more advanced fine-tuning of roasts through the Graph Editor, I'll offer impressions of the quality of IKAWA Home roasts of their provided coffees and some of my own greens. I've started to look at what happens if you change batch sizes, a subject that will be explored in greater depth by later reviewers. My final post evaluates its ease of use and its suitability for potential owners, from new users, to coffee hobbyists and advanced home roasters.

The IKAWA roaster will travel to other Team HB members who will contribute their perspectives. Some are experienced and expert roasters, and some have never roasted coffee. So, let's get started!

(*) Acknowledgments: Thanks to IKAWA Home for sponsoring this review by providing a demonstration roaster and coffee samples. Special thanks to Emily Jackson at IKAWA Home for answering my many questions and to Home-Barista.com early adopters who are exploring this roaster, especially H-B member Gary McCormack (GDM528).

The IKAWA Home Roasting System is a small, high quality, automated roaster. It's built by a company with 10+ years of delivering similar products to market. The roaster case is thick, extruded aluminum. It has a glass top that's held in place by strong magnets. All IKAWA roasters have a "fluid bed" design, which means that hot air keeps the beans circulating while they're roasting. Each unit comes with a trial pack of coffee greens that have QR codes printed on the bags. Users access the recipe for each coffee by pointing their mobile device's camera at the code, which allows them to download the recipe and send it wirelessly to the roaster. These coffee greens can also be ordered on the company's website.

Basic Workflow

To start, plug in the roaster and place it in a well-ventilated area. Although it doesn't create a lot of smoke and is designed for indoor use, it isn't smoke-free. I positioned my unit under a stove hood fan. Next, insert a catch glass with the upper edge sealed with a rubber lip into the bottom front of the roaster. Turn it on by pressing the power button located above the power cord insert. Make sure the profile has been loaded into the roaster from the app in your mobile device. Then measure 100g of beans and pour them into the dosing cup you've inserted at the top of the roaster. Turn the cup to charge beans into the roaster. Then press the round "Go" button at the other side of the roaster to start warm-up, which may only take a few seconds. The app will indicate that roasting has started.*

From here, you can track the automated roast through the app. The sightglass on top lets you watch the bean mass circle the roasting chamber. You'll see the coffee go from green to yellow to tan and brown. Cellulose chaff will come off the coffee and fill about half the glass at the bottom. One or two coffee beans may drop into that glass. That bean ejection is there by design. IKAWA tunes the fan to eject beans that are less dense into the chaff pile in the double-walled glass cup. Most greens have a few defective beans that would otherwise detract from the coffee's flavor, and this step eliminates some of them. Darker roasts may eject more beans into the chaff because they will lose more density during the roast. These often aren't defective and are easy to remove from the catch cup.


Photo by IKAWA Home

When the roast reaches the end of the recipe, the roaster's strong cyclone fan automatically cools the beans while they're still in the roasting chamber. Once the beans cool to near room temperature, the fan stops and the Go button flashes. The app tells you to switch to an empty catch glass. Be sure to remove the rubber lip from the glass that now contains chaff and insert the lip in the empty glass to catch your beans. Now press the Go button. The fan will activate and forcefully expel the roasted beans into the glass. If you haven't inserted the rubber lip, some beans will scatter outside its rim. (You can guess how I know this.)

Empty the chaff from its glass and transfer the roasted beans into a small container with a loose lid, so the roasted coffee can de-gas. Store that coffee at room temperature and away from sunlight for several days, when you'll be able to start drinking it. If you're out of coffee and craving it now, you can prepare a drinkable cup using the Turkish method or grind the beans and let the grounds de-gas for about an hour before brewing. It won't have the full flavor that will develop in a week, but it'll be perfectly drinkable.

When the roast is complete, the app indicates that it's ready to roast again. You can roast another 100g of the same coffee or switch coffees, loading the new profile for your next roast. The IKAWA Home is designed to roast many batches in a row, back-to-back. Smaller amounts of greens will also roast well but will roast darker. Over time you can learn to adjust to the difference by modifying the recipe or stopping the roast sooner.

What I've just described is the basic workflow using IKAWA's curated beans and recipes. But you can also use this roaster with greens that you've bought independently. And, you can vary the recipes to suit your taste. I'll describe these features after the next post, which shows what comes in the box.

* For greater consistency, some H-B users don't just rely on preheating but run the roaster empty to heat the chamber components if the roaster has been idle for more than five minutes. You may not find that extra step necessary. Let taste and convenience be your guide.

What's in the Box

IKAWA has created an exciting introduction with the unpacking experience. Here's how it unfolds!



There are two boxes within the box. The top one contains IKAWA's Round the World introductory coffee selection, and the roaster is packed below.





There's a welcome letter and a scannable QR code. Scanning the code connects you to IKAWA's online introductory materials. They offer an overview of the roasting process for beginners and introduce the app's user interface for roasting.







The roaster comes with a chaff catch cup, a larger capacity bean catch cup with a wider cork rim, and a doser cup that inserts in its top lid. Readers with a sharp eye will see that the two catch cups are identical in the company's promotional photos, so this must be a recent difference. There's a silicone rim that prevents the scattering of chaff or roasted beans and attaches to each cup before it's inserted at the bottom of the roaster.





IKAWA's introductory coffees come in resealable bags.



The back of each bag has a QR code. Scanning it takes you to IKAWA's website's description of that coffee and downloads its recipes to the app. The newer recipes download with the description included.

This post with its two sections is for beginning roasters. Experienced roasters can skip this post and resume with the technical basics post that immediately follows.

How to Taste Your Home-Roasted Coffee -- a Beginner's Tutorial

Taste preferences. Those just starting to roast will find that the IKAWA Home automatically creates a nice variety of light to medium roasts. The recipes for the coffees I received are more attuned to those roast levels. New users with those coffee preferences will be very pleased, especially if they know to let coffee rest for several days or longer after roasting, and if they have learned to let the coffee cool to reveal its full flavor subtleties. People who want their coffee very hot may find the flavor lacking. Coffee enthusiasts like this are often accustomed to drinking darker roasts.

To reflect what I've read in our forums, those accustomed to darker roasts that they may describe as "rich" or "strong" may be concerned that the roaster doesn't live up to its hype. I was easily able to create tasty, dark roasts and will provide guidance later on how to achieve them. IKAWA's online introductory materials cover much ground but could use a post to orient dark coffee lovers.

What about those exotic tasting notes? Beginners may feel frustrated when they read tasting notes that describe fruits, flowers, candy or other flavors, when all they're tasting is light, medium or dark-roasted coffee that may be harsh or mellow. Coffee experts and serious hobbyists like me -- or those who take themselves too seriously -- will tend to enjoy lighter roasts than most of the coffee drinking public. Some of us have discovered these taste preferences at the cupping table, where coffees are roasted very lightly to judge their potential or cull them for defects. Cuppers first taste the coffee after several minutes of steeping. They break the crust of grounds and taste it as it cools to room temperature, when it reveals the most flavor subtleties. Another influence comes from the coffee traditions of countries that vary from very light to very dark roasts.

Coffee experts and hobbyists who enjoy light to medium roasts enjoy sampling coffees in a way that's comparable to savoring fine wines. We look for coffees that balance acidity and sweetness and that show enjoyable signature flavors. The coffee recipes and tasting notes offered with the IKAWA Home System provide an opportunity to start enjoying some of these gourmet levels of coffee enjoyment.

I personally like the range from moderately light to dark and see these as different styles of cooking. So my review covers the range from subtle and complex light roasts of rarer coffees to the rich dark roasts that many also enjoy.

Understanding Coffee Types, Origins and Processing

IKAWA Home's blogs and tutorials are a good starting point for learning about coffee's growing regions and processing methods. During my years as a hobbyist, I've learned that there's always more to know. I'll offer some key points as a brief introduction.

Country of origin. Beginners may want to understand coffees by their country of origin with the expectation that coffee from Ethiopia may differ in recognizable ways from coffee from Sumatra or Central America, for example. This is true to a point. For a long time, coffee producers have sourced seeds and plants from other countries. And, they may apply processing methods practiced elsewhere. So, a washed coffee grown at high altitude in Colombia may taste similar to the same type of coffee plant grown at high altitude in Peru and processed similarly.

Species, Varietals. There are many types of coffee plants, just as there are different species and varietals of many food crops, from grapes to tomatoes and anything else we consume. The two most well-known species of coffee are Arabica and Canephora (aka robusta), and there are several others. Arabica coffees are known for more subtle flavors and are often grown at high altitude, which makes the plant work hard to survive and tends to concentrate flavors in the seed. Canephora or robusta coffees often grow at lower altitude, have higher yield, more caffeine and good resistance to pests and diseases. This species constitutes much of the world's commodity coffees. Better robustas can have fruity or nutty flavors and can have a lasting, creamy mouthfeel and longer shelf life. Such are often an essential component of coffees roasted for espresso in Italy. But the commodity market also has lower-quality robusta with an undesirable burnt rubber taste.

Within species there are varietals. For instance, bourbon and catuai are both Arabica coffees. Some coffees have evolved through natural selection in the wild and others have been intentionally cultivated. Some of these coffees were discovered where they grew naturally, and coffee as we know it originated in Ethiopia, where it grows wild. We can still obtain "heirloom" or "landrace" coffees from Ethiopia and Yemen, and not all coffee varietals have been catalogued.

Over time, coffee has been bred and cultivated to grow in regions that vary by climate, altitude, soil, and weather conditions. Coffee plants have been bred for pest and disease resistance and to offer a variety of flavors, higher yield, and other desirable characteristics. An internet search can bring you much more of this information. Specialty coffees are higher quality than commodity ones and are the focus of forums like Home-Barista.

Coffee beans can also vary in density and size, which is relevant to how they are roasted. Dense beans will need more heat to carry them through the roasting process as will larger beans of comparable density.

Growing conditions. Coffees of the same or similar varietals using the same processing methods and grown in similar altitude, soil and shade conditions will often taste similarly and will respond like each other when roasted.

Processing methods. The IKAWA Home site describes three processing methods for caffeinated coffees: natural, semi-washed and washed.

Natural coffees are typically sun-dried and turned often, with the seed remaining within the cherry. The dried cherry is later removed in a pulping machine but the seed retains more sugars and can include flavors that are very much like recognizable fruits (strawberries, cherries, apricots, pineapple and others) and flowers (such as jasmine, lilac or rose). This processing method is also vulnerable to undesirable, funky ferment, some of which may be described as "wild" flavors.

Semi-washed coffees are run through a pulping mill before they are dried to remove some of the fruit. They are dried with some of the fruit mucilage still on the seed, imparting flavors similar to natural, "dry-processed" coffees.

Washed coffees have the fruit entirely removed from the seed using pulping machinery, fermentation and washing with water. These coffees are less likely to have funky flavors and often yield a "clean" cup.

Decaf. There are two main types of decaffeination, Swiss water processed (SWP) and ethyl acetate or "cane sugar" processing. The latter method uses naturally occurring sugar alcohol to remove the caffeine. Decaf coffees processed from high quality greens can taste very good to the point that it may be difficult to differentiate them from caffeinated coffees in medium to darker roasts. But the very best coffees are generally not decaffeinated. From a roaster's perspective, decaffeinated greens are less dense and must be roasted more gently than their caffeinated counterparts. Decafs taste good enough to me that I sometimes brew some later in the day.

Anaerobic and other processing methods. Coffee farmers and producers are innovating new processing methods to accentuate the better flavors of their coffees and to impart other tastes. Some of these coffees are much more fruit forward than their natural or semi-washed counterparts. Others may taste like rum or hops (without the accompanying alcohol) after undergoing carefully controlled fermentation. Here is a link to a detailed glossary of these methods by Christopher Feran. As many have said before me, coffee roasting is a deep rabbit hole.

The next post will cover technical basics.

Technical Basics -- Ventilation, Heat, Fire Prevention and Electrical Requirements

IKAWA's printed owner manual lists detailed safety precautions. Here are a few highlights for when you're getting ready to roast.

Ventilation. Coffee roasters designed for indoor use cannot emit too much smoke. This roaster produces surprisingly little smoke but must still be properly ventilated. I was easily able to maintain indoor air quality by roasting under a stove fan and either running a portable home HEPA filter or opening a window next to the stove. You don't want to permeate your home with coffee roasting fumes that may smell good at first but are potentially hazardous with long-term exposure.

Here was my humble home setup. I later turned the aluminum tray lip down to avoid interfering with the intake ports on the bottom rear of the roaster. One instance of having that lip too close prevented the beans from spinning, so the roast was a bit darker but was still surprisingly good. As a safety note, IKAWA recommends stopping the roast if the beans aren't spinning. In my one experience they soon started to spin, and it was early in a roast that wasn't ruined by charring.



I've placed metal between the roaster and the induction range to prevent my stovetop from sounding an alarm when it identifies an object that isn't sufficiently magnetic. As you can see, this 5 kg/11 lb roaster is pretty small and measures 240 x 130 x 350 mm or 9.5 x 5.2 x 14 in).

IKAWA takes precautions against coffee beans or chaff catching fire within the roaster. Page six of the printed owner manual suggests temperature and time limits for darker roast profiles to prevent such fires. I was able to achieve a French roast without pushing those limits.

Heat. The sides of the roaster get noticeably warm, and the glass top is too hot to touch for long. The cork grips on the doser and double-walled catch cups allow for comfortable handling.

Fire prevention. In rare instances, especially when roasting dark, the coffee can ignite. IKAWA recommends that if you start getting dark smoke, press the Go button to start the cooling cycle. Also, if the beans don't move in the roasting chamber, those closest to the inlet heat source can catch fire. So, if you see that the beans aren't moving, IKAWA recommends pressing the Go button to start cooling. If the coffee catches on fire, turn off power at the switch where the power cord inserts or unplug the roaster. The fire will safely burn out within the roaster. After it cools, you can empty it. The roaster's electronics also shut it down if heat is excessive. To further avoid fire risk, IKAWA's owner's manual recommends against creating roasting recipes that reach too high a temperature or that roast the coffee too long.

Electricity. This roaster draws a maximum of 1700 W power, and I noticed the lights slightly dim in rhythm with the roaster's pulsed heating. It requires mains power of 110-120V, 220-240V or 220-240V Swiss, and you'll need to order a unit compatible for where you live.

Installing the app. The use of an app can have some disadvantages over a roaster that operates without wireless connectivity. You'll need fairly current devices that run the app. And they must be paired to the roaster, using Bluetooth. The most current version of the Home app uses the Apple iOS mobile and OSx MacBook platforms. The Android version of the Home app will still drive the roaster to follow IKAWA's recipes, but it doesn't yet offer the simplified controls for home users or details about the source coffee.

The app's minimum Apple requirements at the time of this review are:

• iPhone, iPad or iPod Touch running iOS 13.0 or later
• MacBook with M1 processor or later, running MacOS 11.0 or later

My iPhone connected immediately. My new MacBook Air and recent iPad ran into Bluetooth conflicts at first, but I was able to resolve them. I didn't have an iPod touch to use for testing. The app did not install on my old Intel MacBook Air. Once you've established a preferred device, the Bluetooth connection should be stable. If not, it won't be hard to fix. Connection issues may be more of a Bluetooth issue than one with the IKAWA Home roaster. The company's site has a troubleshooting page that you can find in its Support area.

The IKAWA Home App's Provided Interface is Easy for Beginners:
It Can be Supplemented with a Graph Editor for More Advanced Users

People just starting can download the recipes for one of IKAWA's included coffees, then select one they may like and send it to the roaster. The functionality I'm about to describe comes with the app without paying for a subscription. A monthly subscription of $5.99 U.S./£4.99 provides the ability to adjust a graphic representation of inlet temperature, which I'll describe later.

Here are screen shots of a coffee recipe and description on the app. "Filter" recipes have stronger flavors compared to "espresso" recipes, which are milder roasts to accommodate the concentration of flavors when brewing espresso.



You can select the displayed recipe and send it to the roaster as-is or edit it via the Edit button in the upper right. If you're editing, be sure to save your work before sending it to the roaster. Otherwise your roast will follow the recipe that was loaded into the roaster in your prior roasting session.



With the provided app -- without paying for a monthly $5.99 U.S./£4.99 Graph Editor subscription that I recommend advanced users get right away -- a beginning roaster may choose a preferred roast level and development time. The app will display an estimated taste description that characterizes the roast's degree of acidity, bitterness and body. I didn't find that these attributes always correlated with what was produced, but the roasts were almost always pretty good to my taste. For example, if the taste description was "sharply bitter," I found it less so, and when the roast was characterized as dark, it tasted like a darker medium to me.

IKAWA Home has developed its own shorthand for describing a recipe with its roast level and development time. The roast level is described in words, and time in development is listed as +, ++, or +++, a shorthand for low, medium, or high development. Here, the roast level is light and the development time is high.



Because taste preferences are subjective, I don't consider IKAWA's taste descriptions "wrong." What I taste also reflects my preferences, the water I'm using for brewing, my grinder adjustments and brewing times. The water in my house comes from a well and has a whole house system for water softening and filtration.

Each coffee also comes with a description of its origin, producer and prominent flavors. That's accessed by choosing the Info tab. The description is too lengthy to capture in one screen shot, so I'll scroll down to show the rest of it to you.





This photo shows the app running on an iPad.



As the roast proceeds, you'll see whether it is in the drying stage (green to yellow), Maillard (browning until start of first crack), development (1st crack start until ending the roast), or cooling stage. The times of those pre-planned stages are noted on screen and you can follow progress according to the time on the bottom axis of the graph. On all of these graphs, the extra, dashed, vertical lines mark the expected end of the drying stage and the start of first crack, where the beans pop as they release steam. The roaster doesn't sense or measure those events, so the markers are approximate. The IKAWA Home cools the roast very fast, which preserves the flavors targeted by the roast recipe.

Using the Graph Editor for More Subtle Modifications

Let's say you have worked with the roast degree and development settings. You've tasted those roasts, and you're close but not quite there. Maybe you want a roast level between two that you've tried. You can make more adjustments by switching to the Graph Editor, which requires a monthly subscription of $5.99 U.S./£4.99.

I'll describe some simple Graph Editor settings to make finer adjustments to the taste of your roast. The IKAWA Home blog includes a post about using this feature, which I'll also summarize here.

This is a screen shot of a recipe after scrolling down to show you the button for opening Graph Editor. I've set the app to Fahrenheit but can easily toggle to Celsius in the settings accessed through the three line hamburger menu at the top left. (Experienced roasters will recognize that these "recipes" aren't "profiles" of bean temperature (BT) changes because they show intake temperature. Lack of a BT display will not prevent you from modifying the roast profile to your tastes. I'll address that below.)





The red line displays set points for changing inlet temperature. The black line displays fan set points. Temperature set points can be dragged to change heat input and the time it's applied.



Fan set points allow intensity and time modifications of fan speed.



How do heat settings and fan speed affect taste? Emily Jackson's blog post on the IKAWA Home site offers a tutorial on using Graph Editor, which you can find on their site at IKAWA Home > Learn > Blogs. If you're are new to roasting, I suggest starting with one of IKAWA's recipes and changing one setting a small amount, then comparing tastes of the original recipe to your modified one after allowing your roasts to rest for several days or up to a week. If you don't want to wait that long, you can grind the coffee and let the dry grounds off-gas for 1/2 hour to an hour before brewing. After you've made changes, you'll be able to save your new recipe and rename it to track what you've done. Over time, you'll get better at tuning roasts to your tastes.

Inlet Temperature. This is measured where heated air is introduced just below the grate at the bottom of the roasting chamber. IKAWA recipes typically drive a lot of heat into the coffee at the start of the roast to get things started. The beans gain heat more gradually than the inlet temperature reading because they need to heat internally. Experienced roasters typically apply the most heat at the start, when the beans are cool and have about 12% water weight. As water is released throughout the roast, heat settings are dialed back.

Adjusting the first target temperatures downward will create a lighter roast, and too low a temperature may under-roast the coffee, leaving a grassy taste. These are good reasons to start with small changes, one at a time. Reducing peak temperature will create a lighter roast. Generally you'll see that the last temperature setting stays the same or declines. In an air roaster, you don't want declining temperatures well into the roast. You may want to adjust such recipes by having the end temperature maintained or gradually increase.

Bean temperature. You're not seeing bean temperature in these screen shots. Experienced roasters using other software may track the bean temperature rate of rise (BT ROR). Usually that ROR slows toward the end of light and medium roasts and can be tasted as sweetness balancing acidity and presentation of flavors that isn't muted. The IKAWA Home doesn't show BT and the roaster doesn't have a temperature probe to measure that. The next screen shot from the IKAWA Pro roasting software shows the exhaust curve, which also estimates bean temperature and parallels changes in inlet temperature. The Pro software can be downloaded at no charge and can be opened without registering an IKAWA account.



In this curve, there's an initial decrease in exhaust temperature, but that's not measuring the beans, whose temperature is continuing to rise because the beans are still cooler than the exhaust temperature. Past the initial dip, bean temperature will track closer to exhaust temperature. The exhaust temperature curve displayed in the Pro software tracks closely with temperature readings in my drum roaster, where a probe is buried in the bean pile.

The lower line is fan speed, similar to what you see on the IKAWA Home software. Readers who want to mimic profiles created in the IKAWA Pro can do so by adjusting set points in the Home app similar to what you see in the Pro app. The ability to mostly replicate a Pro profile is useful if you buy green coffee from sources that have shared an IKAWA Pro roast profile. In the next section, I show you how to access comparable settings in the Home software -- although the Home app offers fewer set points than the Pro app.

What happens if you adjust heat upward? Accelerating bean temperature quickly late in the roast would char the best flavors out of the coffee. Too high a temperature for an extended time can release unwanted smoke and even cause a fire. If you have a rare instance where that happens, remember to power off the roaster at the switch near the power cord and let the fire burn out internally. IKAWA has programmed safety shutoffs if the Home roaster reaches inlet heat of 290°C / 554° F. For the same reason, it won't allow a roast to extend beyond 12 minutes.

Increasing the time to the next set point during the drying stage will create a less acidic coffee and may preserve some of its more subtle flavors. Gradual temperature changes are generally helpful for less dense and decaffeinated coffees. Coffees grown at high altitude tend to be denser. Excessively increasing temperature early in the roast can rob the coffee of desired sweetness or acidity. Decreasing the time to the next set point will increase acidity and create a more intensely flavored coffee. An excessive setting change here may create unwanted bitter flavors. Stretching out the time in later roast stages can create a mellower coffee, but if the roast runs too long it may bake the intensity and sweetness out of the coffee and leave it tasting papery, dull, acrid, or roasty.

Fan settings. Using set points, the fan intensity can be increased or decreased. You need enough airflow to keep the beans moving. And, if you roast in a place that's cold (below 50°F/10°C) the roaster will automatically shut down, because the fan won't adequately move the beans. Counterintuitively, too low a fan setting will create a darker roast because the inlet air doesn't easily move through the bean mass.

By trying and achieving a French roast with the help of Home-Barista's early adopters, I learned that fan settings at the start of the cooling cycle need to be reduced to avoid ejecting too many beans with the chaff. This is because a dark roast reduces bean density sufficiently to also eject beans that aren't defective. When you smell distillate flavors in the exhaust with a dark roast, it's a good time to start the cooling cycle to preserve those flavors.

The next post will show you how to transpose settings that you can read in the Pro app and input to the Home roaster.

Adapting IKAWA Pro Profiles to the IKAWA Home App

Home-Barista members often split special lots of coffee. Some of our members have IKAWA Pro roasters, and some of the greens suppliers we use post IKAWA Pro profiles with coffees they offer. Although the IKAWA Home software won't allow us to exactly duplicate the settings in the Pro software, you can come pretty close by copying some of the inlet temperature and fan set points that are accessible in the Pro app's data log. The Home app doesn't have that tabular presentation of set points so you can typed them in. You would enter the Graph Editor and drag the wanted set points to the corresponding temperature and time. Here's how you get to the inlet temperature data in the Pro app.



Select inlet temperature.



Select the icon to view edit points.





The Pro software lets you adjust more inlet temperature set points and it has exhaust temperature set points that are not measured or displayed on the Home app and roaster. The IKAWA Pro models have an extra probe to measure exhaust temperature and help the app drive the roast to those settings. As of this writing, profiles stored in the Pro software can be exported as .CSV files or directly to Cropster software that is used by many professional roasters. The Home app doesn't allow such an export, although its recipes can be shared with other Home users. I believe that the Pro app is comparable in the Apple and Android environments (although I don't have an Android device to run that version). Currently the Home app's most fully featured version is implemented for Apple devices. Even though the Pro app doesn't export to the Home app, this needn't be a barrier to creating similar profiles.

Experienced roasters try to minimize the number of temperature and fan adjustments anyway. Some of the Pro profiles I've seen don't use anything approaching the total number of available set points. And, adjusting a Home recipe between set points can include modifying the time between reaching those milestones. The beans don't care what machine they're in or how much you're fiddling with adjustments. In the end, it comes down to using your senses of smell and taste to fine tune a roast. If deciding when to finish a roast, I rely on smelling the exhaust, so if I've set the roast to go a little longer than actually intended, I can hit the button to start the cooling stage at will.

If you want to take a deeper dive into this information, Home-Barista early adopters of the Home system have posted several threads about creating roast recipes to suit their tastes. Our members who can or want to allocate the budget and have the most fully featured IKAWA sample roaster often opt for IKAWA's Pro roaster line or its competitors. With my brief experience using the Home roaster, I don't believe that I have nearly maxxed out its capabilities. I have the luxury of owning a very good drum roaster if I want to perfect a roast, but the IKAWA Home lets me approach the sweet spot for a new coffee in much smaller batches and in an automated, repeatable way.

How Do IKAWA Home Roasts Taste?

Round the World starter kit IKAWA coffees. Here are tasting notes for the five provided coffees. Four of the five tasted good to me. The last one didn't come out the way I wanted, but I'm not sure why that happened, as noted below. Here are my tasting notes.

- Honduras Finca Cual Bicicleta, 100g Espresso Medium +++: 16/51.4 or lungo. Ground with Niche Zero, pulled on Caravel at 201°F / 94° C. Nice balance between sweet and sour. Subtle notes of strawberry, orange, tobacco. Nutty anisette aftertaste changing to candied orange. I recommend pulling this as a normale for more distinct flavors.

- Burundi Kavomo Hill, 100g Filter Light-Medium ++. Clean cup. Pleasantly Meyer lemon, hint of sweet wine, malic acidity when hot. Then juicy, hint of plum as it cools, then hint of lilac. Gets juicier and more balanced as it cools further with a blood orange sweetness to acidity balance. Not as developed as I would like, which might impart more emphasis on plum and wine-like flavor notes. Some grapefruit rind in the aftertaste along with Valencia orange and red grape. This is a good coffee, and I would develop it a bit more for my taste.

Burundi Kavomo Hill, Espresso Medium ++. Pulled lungo in a Caravel at 201°F / 94° C, this is a wonderful shot with bittersweet chocolate, anisette, milk chocolate, pecan, chocolate liqueur, and very mild acidity. It has a lingering and refined chocolate liqueur aftertaste.

- Kenya AA Karuthi filter lt med +++ 100 g. This is sweet and juicy, just the way I like it. When hot, it has red grape sweetness. As it starts to cool, dark chocolate with cola sweetness. Hints of red currant and strawberry as it cools further. Grapefruit rind and citrus acidity in the aftertaste that may mellow as it ages beyond day 6. Cola in long aftertaste. The provided flavor notes are berries, tropical fruits, molasses. I got the berries and the molasses, which I called cola.

- Nicaragua Finca La Argentina Med ++ 6 days post roast: This is a beautiful, elegant coffee. Juicy, pear-like sweet acidity that might also be described as honey. Stone fruit, like apricot. Hint of tropical fruit like coconut, papaya, banana. But these are only hints to describe the delicate sweetness. Mouthfeel and acidity are like a pinot noir. The provided flavor notes are cherry, orange, cinnamon. I get the cinnamon as it cools. At this roast level I'm not getting orange. I can see cherry describing the delicate sweetness. This recipe is described as smooth, balanced, medium body. That all fits.

It really shines as espresso med ++ where it has a rich, mousse-like mouthfeel. The taste when hot is honeyed Meyer Lemon and orange with a lemon finish and a Baker's chocolate aftertaste. This was a normale in a Caravel. Longer development or "+++" takes it to less sweet, lemony dark chocolate with a Reese's cup chocolate peanut aftertaste.

- Ethiopia Buie Bora Yirgacheffe Filter Light-Medium +++ 50.5g roast : Day 6 post roast. The expected tasting notes listed in the recipe are lemon, black tea, honey. I noted caramelized and malty flavors with mild, malic acidity when hot. Sweetness opened up as it cooled. There was dark chocolate with malic acidity on the back of my tongue as it cooled further, when it tasted a bit flat and papery, characteristics that could come from a baked roast defect. The 100g roast tasted more flat and papery. Sampled 19 days post roast, it wasn't papery, but the acidity was flat and a bit leathery. Rested coffees can lose top notes in the taste spectrum or the coffee can open up sufficiently that apparent defects disappear. Papery, flat flavors can occur if a fluid bed coffee roast is developed too long, which would cause the roast defect. The greens themselves may have aged enough that they're drier. Also naturally occurring yeast can stale green coffee over time. The leathery taste could have appeared because the greens are aging. Since I no longer have the roaster and have gone through my supply of this coffee, I'll ask other reviewers to try it, perhaps shortening the time in development.

My own greens. The supplied greens and recipes did not include any dark roasts. I tried one of IKAWA's legacy recipes with Mysore Nuggets Chikmagalur District greens sourced from Coffee Bean Corral.

The El Mirador, Italian Roast legacy recipe 100g roast with a single pull on my Caravel and the basket fully loaded at 15 gm at 178°F / 81° C yielded a very nice espresso with a creamy fudge mouthfeel and chocolate Ovaltine taste. The beans had drops of oil on the surface. This shot was pulled 16 days post roast.

I had less luck with these beans with IKAWA's La Florida, Colombia, French roast recipe that didn't taste like it was roasted dark through and through and had a strong bitterness. I chalk that up to using the wrong recipe for that coffee.

Using a recipe developed by H-B member Gary McCormack, aka GDM528, achieved a very good and fully rounded "American-style Italian roast" with oil sheen covering the surface of the beans and some craters that you might typically see in roasts well into second crack. (Coffees roasted in Italy vary in roast level, and their dark roasts typically have lower acidity.) Tasted 9 days post-roast, this coffee was like intense, bittersweet dark chocolate. When people say they like a bold, rich cup of coffee from Starbucks or Peets, this is what they mean. But this was fresh roasted coffee at home. To me, this didn't taste burned when brewed in an AeroPress at 175°F / 79° C. This is a style of cooking like when you make a dark roux that's very caramelized. It's the second-wave roasting style that you'll typically find at Caffe Trieste in San Francisco or Connoisseur Coffee south of San Francisco.

This recipe hits a higher peak inlet temperature and then declines. I let it run to the finish and didn't experience extra smoke at this roast level. People experienced with air roasters avoid a temperature decline, especially late in the roast. Would this dark roast have improved if cooled at that point of development with the temperature steady or rising until then? Later reviewers might download the recipe below and adjust the end so that temperature doesn't decline, and then compare tastes with the original recipe. Even with the temperature continually rising, the exhaust gives good feedback on how the roast is proceeding, so an experienced roaster can start the cooling cycle when they smell what they want.

Darker into 2C

Here is how the beans looked.



At the other end of the roasting spectrum, I tried Haitian Blue Mountain greens and roasted them as light as possible with short development, using the IKAWA legacy filter recipe for Brazil Sitio Matinha Filter. This was a wonderful melding of roast profile and green, where the very low acidity of the coffee worked well when roasted for low density greens. Because the acidity is low, I pulled it as an espresso. It has a creamy, buttery mouthfeel and is extremely well-rounded. The sweetness/acidity balance is like very mild apricots.

And, I had successful roasts of a Panama Esmeralda Gesha, where the greens were stored a bit too long, so they'd lost the complex, volatile flavor notes, such as jasmine, but it was still a refined coffee with a nectar-like sweetness balancing very mild acidity. I used IKAWA's recipe for Kemgin Gesha, and the roast itself seemed perfect. I edited the Filter Light-Medium ++ back to the shortest development time and dropped it a bit early by smell.

Here's a link to the IKAWA Home recipe library. You'll find two recipes for Kemgin Gesha by scrolling down to the Panama section.

I have an anaerobic coffee where I prefer to stretch out the roast to decrease its intensity as experienced with my drum roaster. I was able to achieve that mellowing effect when slowing down the drying phase with the Graph Editor and extending development time. It was more muted than I wanted, but that's another possibility a later reviewer might try. It's not very different when roasting the same coffee for drip versus espresso, a practice that's less common these days but has the same intention.

I also tried changing batch sizes using the same recipe at 100g, 75g and 50g. My results were inconclusive and a bit puzzling, with the lightest roast at 100g, the next lightest at 50g and the darkest at 75g. One of our early adopters briefly reported similar results. Why does that happen? Since it was time to move the roaster along, I will ask other reviewers to try different batch sizes and report their results. If their experience is similar, the batch size differences may be discussed further in one of our user experience threads.

In the end, the IKAWA Home had to go out the door when I would have enjoyed more exploration of my greens in very small batches.

Is the IKAWA Home System a Good Fit for You?

Beginning roasters. If you've never roasted before, you'll reduce your initial learning curve. You'll get repeatable medium and light roasts of quality coffees for drip and espresso brewing. The IKAWA Home app comes with an interface designed for home users without prior roasting experience. For a monthly subscription price of $5.99 U.S./£4.99, you can make more fine-tuned adjustments that you may not find necessary at the start. Those who like dark roasts may feel that some provided coffees and recipes fall short of their preferences. But the roaster can produce delicious dark roasts, as discussed in the prior post.

At this time, Home users will want to run the app in a recent Apple iOS or OSx environment. The Home app offers more features than the Android version that is still available for download. The Android app is configured as the Graph Editor, which beginners may not easily understand.

Coffee hobbyists used to fresh coffees from professional roasters may not immediately find comparable predictability with IKAWA's provided coffees and recipes, and less so with their own greens. But that situation can vary because coffee is an agricultural crop and even conditions at a professional roaster can vary. Pros also change blended coffees to accommodate available supply.

Intermediate roasters. Compared to other small, budget-priced home roasters, the IKAWA Home offers an upgrade in consistency and workflow at an intermediate price. Its small batch size permits multiple runs at rare greens or small samples, and it helps you decide a general approach if you have a larger roaster. You also won't have very many roasts that totally fail. And you can avoid some dialing in by sharing recipes with other Home users for the same or similar greens.

The Home's interface lacks features you may want. It isn't an effective learning tool for tuning bean temperature profiles compared to Artisan or Cropster software. You also won't be able to download and use automated IKAWA Pro profiles posted by some specialty greens suppliers. You can use such profiles as guidelines for adjusting the Home's recipes, but you won't be able to input the same number of settings as those available with the Pro. However, if you can tune roasts by smell and visual bean changes, you may find that the IKAWA Home roaster is sufficiently capable.

Advanced and professional roasters. The IKAWA Home only uses an intake temperature sensor, and you can adjust intake heat settings and fan speed. But it lacks the Pro's exhaust temperature sensor, the Pro app's mature implementation for Apple and Android platforms, and the Pro app's exhaust temperature settings and exhaust temperature rate of rise graph. And the Pro has more adjustable set points for fine-tuning roasts. And it allows you to include notes.

By customizing your own recipes and saving them, you could use the Home for old-fashioned light sample roasts for cupping. But professional sample roasters now provide full profiling capabilities for production and competition roasting, and the Pro's app can export profiles to Cropster. However, the added features of the Pro come at several times the price of the Home.

Ease of use

The IKAWA Home's automation means you can watch it roast without hovering over the dials. Its Bluetooth wireless link can be fussy to set up, but that's generally an issue across Bluetooth connections. Once you have it set up and are using it mostly with a preferred device, the wireless interface works reliably.

For beginners, the upgraded app's simple interface for tuning roasts will avoid deep dives into the rabbit hole of roasting theories. But even if you upgrade the app with the monthly Graph Editor subscription for $5.99 U.S./£4.99, it could be better designed to help users find and store recipes from the company's website. That's because the list of Coffees is also where you'll find the more comprehensive list of stored recipes. But that's something you discover by stumbling onto that setting rather than finding it via the app's menu icon. Here's what I mean:



Tapping "Coffees" displays the recipe list and vice versa. If you tap "Recipes," it'll bring up the Coffees list.



Also, the app's general description of tastes after adjustments don't match what I was tasting, especially its characterizations of bitterness that I often found overstated.

You may think you selected one recipe to roast but find yourself using another recipe. This strikes me as a new user's error. You need to make sure that the intended recipe is loaded into the roaster, unless you are roasting the same recipe back-to-back. If you select a different recipe and press the menu button to send it to the roaster, it takes a short time to load. If you create a new recipe, you need to make sure to save it and then load it. I chalk this one up to gaining user experience and not a flaw in the roasting app.

Another point of mild frustration is finding that dark roasts often eject excessive beans into the chaff pile. Ejecting beans into the chaff is a useful function for lighter roasts where defective beans are often less dense than the rest. But you may want to adjust the Cooling fan setting downward for darker roasts.

Cleaning is minimal. It involves manually cleaning the catch glasses with a dry microfiber cloth or hand washing them after removing their cork housings. You'll probably clean the top glass fairly often, washing it by hand. It's held in place by magnets. IKAWA doesn't recommend using a dishwasher. The roasting chamber can be gently cleaned with a dry microfiber cloth. The company tells you not to use liquids to clean the roasting chamber because leakage of liquids below the inlet grate can damage the electronics and void the warranty.

IKAWA Home is continously adding educational and support content to its website. Some of that information is very helpful. I would like to see better guidance for beginners who prefer dark roasts.

Quality

The roaster itself seems to be well-built. It's mechanically consistent and has an attractive design. The quality of provided coffees and recipes is generally good. It's able to produce all roast levels.

Conclusions

I can recommend the IKAWA Home as a very good alternative to far more expensive sample roasters. By the time it left my hands, I wanted one to continue experimenting in small batches with automated profiles. Here are my ratings, keeping in mind that other reviewers are now developing their independent impressions.

Overall: (3.5 out of 5)
Roaster performance: (4 out of 5)
Quality of roasted coffee: (4 out of 5)
Ease of use: (3 out of 5)

I expect users' subjective experience of these ratings to improve as:

- They become more experienced in selection of recipes, in using generalized recipes as starting points for their own greens, and in adapting Pro recipes they may find online
- As the Home app's user interface evolves and is adapted to Android devices
- As the company's Home website content and the ease of finding that content are continuously improved

This review is still in progress, so you can look for most posts by Team HB Members, so it's currently closed for comments. But we want to encourage discussion, so I've just opened a thread for HB members here:

IKAWA Home Roasting System Review Discussion


Note: After completing my review, I liked this roaster so much that I bought the used review unit at a fair market price.