Tamping is a step in espresso making that seems simple but is full of subtle knowledge. Baristas have different understandings of tamping: some believe a light press to level the grounds is enough, while others are used to pressing down with full force. So, does tamping pressure actually affect the extraction result? Front Street Coffee conducted two sets of comparative experiments, using coarse-ground and fine-ground coffee powder respectively, and observed the changes in extraction time after tamping with different pressures. The experiments revealed a key rule: the effect of tamping pressure on extraction is not fixed, but is closely related to the coarseness of the coffee grounds. This article will take you deeper into the true role of tamping, the differences in understanding among different schools of thought, and how to flexibly adjust tamping pressure according to grind size, so that every cup of espresso is more stable and outstanding. [more…]

Cold brew coffee usually requires 8 to 12 hours of low-temperature slow extraction, but what if you want to drink it the same day? Raising the water temperature can speed up extraction, but if you use hot water directly, it becomes hot brew, and the floral and fruity aromas and low bitterness unique to cold brew will also disappear. Front Street compared three methods through experiments: conventional 23°C cold water extraction for 10 hours, 40°C warm water extraction for 4 hours, and 92°C hot water blooming followed by room-temperature water extraction for 4 hours. The beans used were Colombia · Hanami, with full berry acidity, floral notes, and pink pepper flavors. The results showed that the 40°C warm water rapid cold brew was closest to the performance of conventional cold brew, with both a fermented feel and clearly presented flavors, making it suitable for friends who want to drink cold brew quickly. [more…]

In the three-pour method for pour-over coffee, the timing of the third pour is often overlooked—should you wait for the coffee liquid to completely drain before pouring, or should you top up promptly once the water level drops by half? Front Street Coffee conducted two sets of comparative experiments, using Costa Rica Strawberry Candy and washed Yirgacheffe beans respectively, to analyze in depth the practical differences between the two pouring methods from the dimensions of aroma, flavor, extraction time, and coffee bed state. The experiments revealed how the timing of the pour affects the temperature of the coffee bed, fine migration, and the final flavor performance, while also explaining why beans of different hardness show completely different results when faced with waiting for the liquid to drain. This article will present the full experimental process and conclusions to help coffee enthusiasts understand the core logic of judging when to pour in the three-pour brewing method, and provide Front Street's practical recommendations. [more…]

Espresso extraction involves numerous variables, and portafilter temperature is often overlooked. Front Street Coffee designed a comparative experiment to address the question of "whether the hot or cold brew head affects tamping force": keeping dose and yield fixed while only changing the portafilter temperature, recording time, concentration, flavor, and milk-coffee performance. The experiment used Front Street Sunflower Warm Sun Blend, and the results showed that although temperature did not significantly change the extraction yield, it clearly steered the flavor direction—a preheated portafilter made the full-bodied feel and winey notes more prominent, while a chilled portafilter amplified the fruity acidity and light texture. This article will present the complete experimental data and tasting conclusions, and answer whether tamping force needs to be adjusted with temperature, as well as how to decide on a portafilter preheating strategy based on the coffee bean roast level. [more…]

Water temperature is an extremely critical part of pour-over coffee extraction. It not only determines the degree to which coffee compounds are dissolved, but also directly influences the final flavor direction. Through a comparative experiment at Front Street Coffee using the washed beans of the Yirgacheffe Guddina Cooperative, this article brews at five water temperatures—80°C, 86°C, 90°C, 93°C, and 96°C—observing the changes in acidity, sweetness, tea-like character, and astringency, and offers practical advice on choosing water temperature according to roast level. At the same time, starting from the lignocellulose structure of coffee beans and the structure of soluble aroma molecules, it explains why different water temperatures bring about completely different flavor layers, helping you avoid over-extraction bitterness or under-extraction blandness in your daily brewing. [more…]

Wetting the filter paper before brewing coffee is almost a standard step for all pour-over enthusiasts, with the usual goals of making the filter paper fit snugly, removing paper dust, and, if hot water is used, warming the cup along the way. However, most tutorials rarely discuss in depth how much the degree of fit between the filter paper and the dripper actually affects the final taste. Front Street conducted two sets of controlled experiments, using V60 and KONO drippers respectively, paired with filter papers in different states of fit for brewing, and tasted and compared them one by one. The experiment used the floral-fruity Front Street · Gedin Gedin and the nutty-sweet Front Street · Brazil Red Bourbon, and the results showed that a poorly fitting filter paper significantly changes the flow rate, which in turn affects the extraction yield and concentration, producing noticeable differences in mouthfeel. [more…]

At the 2016 WBC, Taiwanese competitor Berg Wu won the championship with a frozen portafilter extracting espresso, overturning the perceptions of the judges and audience at the time. Can portafilter temperature really influence the flavor of an espresso? Through extraction experiments comparing high-temperature, room-temperature, and frozen portafilters, Front Street Coffee found that the three indeed show clear differences, and the effect brought by the frozen portafilter is especially far removed from the other two. This article will analyze in detail the principles behind how portafilter temperature affects espresso, and share Front Street Coffee's actual test conclusions, helping you reunderstand this easily overlooked extraction variable. [more…]

Many coffee enthusiasts have heard the claim that a long bloom time can lead to under-extraction. This idea seems to contradict our usual understanding of what blooming does. Blooming is meant to release carbon dioxide and improve extraction efficiency, so why would a longer bloom time actually lower the extraction yield? In this article, we compare brewing experiments with two bloom durations—30 seconds and 1 minute 30 seconds—measuring concentration, extraction yield, drawdown speed, and water temperature changes, in an attempt to reveal the true relationship between bloom time and extraction results, and to explore under what extreme conditions an overly long bloom might actually cause under-extraction. [more…]

When tasting a new bean, why is it recommended to choose a hot brew first? This article delves into the flavor differences of black coffee made by pour-over, French press, siphon, and other methods under hot brewing and iced brewing from the perspectives of extraction yield, concentration, water temperature parameters, and so on. Taking pour-over coffee as an example, the article specifically compares the different settings of hot brewing and iced brewing in terms of coffee-to-water ratio, grind size, water temperature, and other parameters, and explains why iced brewing often requires sacrificing part of the extraction yield in exchange for higher concentration. At the same time, it also explores the influence of temperature on aroma, taste, and aftertaste, explaining why hot coffee can more fully present the complete picture of a bean. [more…]

Among the many variables in pour-over coffee, water temperature has a particularly direct impact on the extraction result. It not only determines the speed and sequence with which flavor compounds are released from the coffee, but also ultimately shapes the acidity, sweetness, bitterness, and body of a cup of coffee. In this article, through comparative experiments conducted by Front Street Coffee using washed Yirgacheffe beans, five water temperature groups of 80°C, 86°C, 90°C, 93°C, and 96°C were used for brewing, recording the flavor differences and analyzing the relationship between water temperature and extraction yield and concentration. At the same time, the article also provides the recommended water temperature ranges for light-roasted and dark-roasted coffee beans in daily brewing, helping coffee enthusiasts make more suitable choices for different beans. [more…]

Among the many variables in pour-over coffee, pouring technique is often overlooked by beginners, yet it has a significant impact on the final flavor. The speed of the circular pour is essentially equivalent to the amount of agitation applied to the coffee bed, so how much difference can it actually make to the taste of the coffee? Front Street conducted comparative experiments using washed Yirgacheffe and dark-roasted Golden Mandheling, measuring concentration and extraction yield and combining this with actual tasting to verify the effect of different pouring speeds on flavor. This article will present the parameters and results of both experiments in full, and further explore the role that agitation intensity plays when conditions such as grind size are changed. [more…]

When making espresso, does tamping pressure actually affect the final taste? Front Street Coffee has been asked this question many times. To provide an answer, Front Street Coffee used 20g of coffee grounds and a target liquid weight of 40ml, extracting three espressos each with light tamping at 2kg, heavy tamping at 18kg, and no tamping at all, then compared extraction times and flavor performance. The results surprised many: the extraction times for the three methods were almost identical, and the tastes were hard to distinguish. The key behind this lies in how the coffee machine's 9bar pressure actually works. Starting from experimental data, this article will clarify the real impact of tamping pressure and explain why even distribution of grounds is far more important than forceful tamping. [more…]

Among pour-over coffee pouring techniques, the size and speed of the circular pour are often discussed, but whether the direction of the circle affects extraction flavor has also become a question many enthusiasts are curious about. The spiral ribs of the V60 dripper are arranged clockwise, and some believe that pouring in the same direction can guide the water flow along the ribs and improve uniformity, while pouring counterclockwise may create turbulence by hitting the ribs and change the extraction result. To verify this claim, Front Street conducted a comparative experiment using the same parameters, changing only the pouring direction, and compared extraction time, concentration, and flavor performance one by one. This article will outline the experimental process and conclusions, and explain which pouring factors are truly worth paying attention to. [more…]

What should you do if your coffee is too bitter? Some people suggest that adding salt can improve the taste. In this article, through a controlled experiment with Mandheling coffee, we tested the effects of three different amounts of salt—0.01g, 0.02g, and 0.03g—on the coffee's flavor. The results showed that 0.02g of salt balanced the bitterness and saltiness, enhanced the body, and made it easy to drink; while 0.01g still had a pungent taste, and 0.03g was too salty. The experiment showed that adding salt can indeed mask bitterness to a certain extent, but similar to the bypass method, it is mainly suitable for rescuing extraction mistakes or coffee that is about to go wrong. If the coffee itself is perfectly extracted with balanced acidity and sweetness, adding extra salt will instead disrupt the flavor balance and artificially create negative tastes. [more…]

Pour-over coffee is usually extracted only once, but recently a method called "double pour-over" has attracted attention—pouring the already-brewed coffee liquid back into the coffee bed in the dripper for a second extraction, which is said to make the coffee sweeter. Front Street Coffee specially designed a set of comparative experiments for this, selecting three single-origin beans with different roast levels and conducting regular pour-over and second-round re-pouring respectively, comparing them one by one across dimensions such as aroma, acidity, body, and finish. The experimental results show that, provided the beans are of good quality and the parameters are properly controlled, second-round re-pouring can indeed enhance intensity, but not all roast levels are suitable. This article will present the complete experimental process, brewing parameters, and flavor comparison results, and provide suggestions for bean varieties suitable for trying double pour-over. [more…]

Some coffee enthusiasts like to try mixing ingredients such as osmanthus, granulated sugar, or butter into the coffee puck before extracting espresso, hoping to achieve a more naturally integrated flavor. But is this approach really feasible? Front Street conducted a comparative experiment, mixing granulated sugar into the coffee grounds and adding it directly into the cup, to observe the differences in flavor and extraction parameters of the espresso produced by the two methods. The results showed that sugar mixed into the puck caused the extraction time to shorten significantly, with a sharp and separated taste, while the method of adding it directly into the cup produced a surprisingly well-integrated effect. This article will analyze the experimental process and the reasons behind it in detail, helping readers understand why mixed extraction often backfires. [more…]

Tamping the puck flat is a basic consensus in espresso extraction, but how much force should actually be used to tamp it down has long been a point of disagreement among baristas. Some give the tamper a light spin and apply just a little pressure, while others put their whole body weight into compressing the puck as hard as possible. Front Street conducted a comparative experiment using two grind sizes—coarse and fine—tamping with a regular force of 1.5 kg and a full-force press of about 9 kg respectively, to observe changes in extraction time. The results showed that because coffee grounds differ in density, the force needed to reach a compacted state also varies: fine grinds require greater pressure to be tamped to their most compact state, while coarse grinds are already sufficiently compacted at 1.5 kg, and full-force tamping produces extraction results almost identical to regular force. This article will present the full experimental process and conclusions to help coffee lovers understand the relationship between tamping force and grind fineness. [more…]

The most fascinating thing about cold brew is that it works like a slow-motion projector: the flavor release that hot extraction completes in a few dozen seconds is stretched out over more than ten hours, and the character of every flavor compound is amplified and put on display. Running a set of cold brew comparison experiments with beans processed in different ways lets you directly see how each processing method truly expresses itself at low temperatures. The experiment is set [more…]

Tamping is a seemingly simple yet highly debated step in espresso making. Some people casually rotate the tamper, while others put all their strength into pressing the puck as tightly as possible. Just how much does tamping pressure affect extraction? Does the compactness of the puck really influence flow rate? Front Street Coffee answers these questions through two sets of comparison experiments with different grind sizes, using actual extraction time data. This article will guide you through the subtle relationship between tamping pressure and grind particle size, helping you find the tamping method that suits you best. [more…]

Cold brew coffee is extracted in a low-temperature, still environment, and many people habitually assume that grinding the coffee finer will increase its strength—but is that actually true? Through comparative experiments, Front Street Coffee found that a coarser grind actually yields a higher TDS reading in cold brew. Starting from the underlying logic of water temperature and particle movement, this article will explain why the "finer grind equals stronger coffee" theory that applies to high-temperature pour-over does not hold for cold brew. It also offers coffee bean recommendations suitable for cold brew, suggested coffee-to-water ratios, and points to note on grind selection for beans of different roast levels, helping you make a specialty cold brew with just the right strength and an aroma that isn't masked by added ingredients. [more…]