As the resident coffee guru on the tastings and testings team, I’m a little ashamed to admit that even after years of interviewing coffee experts, attending coffee conferences, and reviewing coffee gear, my personal coffee preferences haven’t changed. While I can truly savor an expertly brewed artisanal cup, a lot of coffee aficionados would scoff at my beloved daily drink, which commits three major coffee industry sins: it’s iced (not cold brewed), it has enough cream and sugar to make it taste like a milkshake, and it is procured from a major retail chain not exactly known for artisanal coffee. But if there’s one thing I’ve learned reviewing coffee gadgets, it’s that there are die-hard java geeks who will spend hundreds of dollars on gear they perceive will get them the perfect cup of coffee, and there are others, like me, who love coffee but don't care that much about fancy beans and exacting brewing techniques. Here in the test kitchen, we use coffee refractometers and other methods to assess coffee quality, but what really matters is: Does it taste good?
When we last tested coffee makers we named a winner that makes exceptional coffee, but costs almost $300. Meanwhile, less expensive coffee maker brands remain ubiquitous fixtures in many home kitchens; so do you really have to spend more than $100 to get a decent coffee maker?
To find out, we chose nine coffee makers to test. They had stated capacities ranging from 8 to 14 cups and were priced from about $25 to about $95. The high end of that range included the Best Buy option from our high-end coffee maker story: the Bonavita 8 Cup One-Touch Coffee Maker (about $95).
We started out getting to know the coffee makers by brewing 12 ounces, 32 ounces, and full pots of coffee in each machine, evaluating how easy the machines were to load, program, pour from, and clean. While most coffee machines come with scoops and usually recommend using one scoop of ground coffee per “cup” of water (see “How Big Is ‘One Cup’?”), through years of testing we’ve found this ratio is typically too weak for our tastes. In order to give every machine a fair shot at making good coffee and keep our testing consistent, we used the Specialty Coffee Association (SCA) recommended ratio of 1 part coffee to 18 parts water, weighed and measured in grams. Most of the machines hold about 72 ounces of water, which means that brewing a full pot would require about 4 ounces of ground coffee using the SCA ratio. However, the baskets of three of the machines were too small to hold 4 ounces of ground coffee; they overflowed once the water started pouring in, creating a mess of ground coffee backflowing into the water tank—a huge pain to clean. This means that we couldn’t make a complete pot of full-flavored coffee in those three machines.
Most models were straightforward to operate; usually as simple as adding water, a filter, and coffee, and pressing a button—an easy task anyone can perform while half asleep in the morning. Most usability issues were minor. In order to fill the ground coffee container in one Mr. Coffee model, we had to rotate the hot water spigot away from the filter, add the coffee, and then rotate the spigot back in place. If we forgot, the hot water would flow back into the water tank instead of over the coffee. Not a deal breaker, but an extra step to remember every morning. Only one product was truly a pain to use: a model made by Hamilton Beach that replaced the external coffee carafe with an internal tank that holds the brewed coffee. To fill our mugs, we held them up to the coffee machine and pushed a button to dispense the coffee from a spigot; however it wasn’t tall enough to accommodate larger travel mugs or carafes. Its many components were a puzzle to put together each time we brewed and cleaned the machine.
We also preferred products with insulated thermal carafes over glass. Coffee machines with glass carafes have hot plates to keep the coffee warm, whereas machines with thermal carafes don’t, and instead rely on the insulation of the carafe to keep the coffee warm. We liked the latter better; they didn’t scorch or overcook the coffee the way glass carafes sitting on hot plates do over time. We also liked carafes with responsive pouring mechanisms that made it easy to control the flow of coffee into our mugs. Our favorite coffee maker had a carafe with an ultraresponsive lever that started and stopped the flow quickly.
Otherwise, we preferred coffee machines with simple controls, minimal components that were easily accessible to clean, and clear indicator lights or beeps that told us when the coffee was done brewing.
We also wanted a coffee machine that, well, made good coffee. Besides the quality of the water, there are a lot of factors that impact how coffee tastes: the type of beans, how they’re roasted, and how finely they’re ground. We kept all these variables consistent by using tap water and bulk medium-roast beans that we ground in batches in a commercial grinder. By keeping those variables consistent, we could focus on two design features of the coffee makers that impacted the quality of coffee produced: brew time and temperature.
When hot water streams through coffee grounds, it penetrates small channels in each coffee particle, extracting its chemical compounds. Some of these compounds are cocoa-y, with pleasantly bitter and floral notes, while others are excessively acidic, with oily or acrid notes. Brewing coffee is all about maximizing the good flavors and minimizing the bad. Experts at the SCA have agreed on a set of standards backed by scientific research to ensure success when using a home coffee machine. Namely they stipulate that drip coffee makers should brew hot and fast and ensure that there’s thorough contact between the water and the ground coffee. To gain the “certified home brewer” designation, the water should be 195 to 205 degrees Fahrenheit when it reaches the grounds and the brew cycle should take less than 8 minutes for a full pot of coffee. Water that is not hot enough does a poor job of extracting the good flavor compounds from coffee, while water that is too hot extracts the bad compounds and results in burnt-tasting coffee. A brew time that lasts longer than 8 minutes will also extract those bad flavor compounds. Plus, it’s a pain to have to wait for what seems like ages for coffee to brew in the morning.
Prior to doing any testing, we contacted Peter Giuliano, SCA chief research officer, to learn more about the SCA’s testing practices. He told us that they use a specially designed thermometer to track the temperature of the hot water as it enters the brewing basket. With the SCA’s guidance, we set up our temperature test to be the closest possible approximation, tracking the temperature of the water in each machine as it entered the brew basket as well as timing each brew cycle. The results were surprising: only one of the machines in our lineup met all of the SCA standards. Some spent zero time of their brew cycle in the right temperature zone. Only one machine stayed at the recommended temperature of between 195 degrees and 205 degrees for a significant duration of its brew cycle. It performed far and above the rest: while most coffee makers spent less than 10 percent of their brew time in the correct temperature zone, our top model stayed in the zone for more than 70 percent of the brew cycle. We saw the effects of these drastic differences in time and temperature when we tasted the coffee and measured its extraction.
We used an instrument called a coffee refractometer to measure total dissolved solids (TDS) and calculate the brewed coffees’ extraction levels, a coffee industry term for how much of the ground coffee compounds end up in a final brew. Generally speaking, too-low levels of extraction result in watery, sour coffee, while too-high levels of extraction result in harsh, overly bitter, or burnt-tasting coffee. An optimal extraction level, one within a range of 18 to 22 percent, results in a smooth, balanced, and full-flavored cup of coffee. Of the models we tested, only three (those with shorter brew cycles and longer duration in the 195 to 205 degrees temperature zone) were able to make coffee with extraction levels that sat within the desired range. The extraction levels for some of the brews were as little as 11 percent; essentially water with just a hint of coffee. Temperature tests showed that the water in the machines that made weak coffee didn’t get hot enough to extract the compounds needed for good coffee flavor. It’s also likely that their prolonged brew times—up to almost 10 minutes for a half pot—pulled too many of the compounds that contribute bad flavors to the brew. To brew full pots of coffee (a task that, according to experts, that should take from 4 to 8 minutes), some of the machines took 20 minutes—an egregiously long time, both for practical and quality reasons.
Because the most important metric when evaluating coffee is how it tastes, we held a blind, randomized tasting of the coffees brewed in each machine using a standardized amount of 51 grams of coffee to 920 grams of water (the SCA recommended 1:18 ratio). The tasting results echoed what our temperature, time, and extraction level tests did: Models that brewed lower and slower tasted watery and stale, while machines that brewed hotter and faster made smooth, robust tasting coffees. Our top-rated coffee machine took only 7 minutes to brew a full pot with water that heated to 200 degrees within minutes. Its coffee was the most robust and flavorful of the bunch.
Ultimately, we named the Bonavita 8 Cup One-Touch Coffee Maker (about $95) as our top inexpensive coffee maker. Also named the Best Buy in our high-end coffee maker testing, this model aced all our tests, brewing full pots of coffee in just about 7 minutes and staying in the target temperature zone for 71 percent of the brew time. Its coffee was robust and flavorful, and was given the top score by our tasters. This model was also the only one in our lineup certified by the SCA’s home brewer program as meeting all its standards. At about $95, this is a product for coffee lovers like me that want a premium product at a not-so-premium price.