As coffee has gradually become more widely recognized, specialty coffee promotion in cafés has emerged in response, and we too have begun tracing things back to their roots—we have come to treat coffee as culture. The rise of specialty pour-over coffee undoubtedly reflects the demands of the market and the needs that cafés have identified. Café counters have also begun to lower their "status," no longer featuring the early design of a bar raised a foot high. [more…]

Heytea recently launched a seasonal limited-edition drink, Litsea cubeba Yunnan papaya, combining western Yunnan sour papaya, Xishuangbanna litsea cubeba, Lingnan fresh carambola, and litsea cubeba pea jelly. Officially, it is positioned as having a distinctive sweet-and-sour taste. However, after the new product hit the market, evaluations on social media quickly split into two extremes: some were put off by the piercing sourness, some chose "less less less sweet" yet tasted only sweetness, and the sugar-free version was criticized for being overall too sweet with the fruit aroma not standing out. Why can the same cup of drink deliver such wildly different impressions as "sugar-free salted lemon Seven Up," "flat salt soda," and "hot and sour noodles"? This article sorts through feedback from all sides and explores how fresh fruit batches and individual differences in sourness tolerance affect the final flavor of this limited edition. [more…]

Coffee tasting goes far beyond taste—it is a coordinated experience of sight, hearing, touch, smell, and taste. This article starts from the interactive setting of a specialty coffee shop and delves into how to train and build your own coffee sensory system through daily accumulation and professional tools. You will learn how smell pulls on taste memory, how the tongue distinguishes the five basic tastes, how touch perceives body and smoothness, and how to use aroma kits such as the 36-aroma coffee nose and the 100-flavor flavor map for deliberate practice. Whether you are a coffee enthusiast or a professional, this method can help you read the flavors in the cup more clearly, making every tasting more enjoyable and more precise. [more…]

Many coffee enthusiasts have encountered this confusion: you go to a café and order a black coffee, and it tastes so sour it makes you frown, yet the barista says this is just how coffee is supposed to taste, and that if you drink black coffee you have to accept the sourness. At the same time, some roasters claim that coffee beans are fruit, that they only have acidity and sweetness, and that any bitterness is a sign of bad beans. Do these claims really hold up? This article will, from the perspectives of the nature of coffee beans, the chemical changes during roasting, and the flavor characteristics of different origins, help readers clarify the relationship between "sour coffee" and "good coffee," and teach you to distinguish between a quality "fragrant acidity" and a "dead acidity" caused by negative factors. [more…]

Many people notice a distinct sourness when drinking Americano and can't help but wonder: is this sourness normal? In fact, sourness in coffee isn't necessarily a bad thing, but if it's unpleasant, it often means something went wrong somewhere. From the roast level of the coffee beans and how long they've been stored, to the grind size, brewing water temperature, and even the temperature changes after the coffee is made, every variable can heighten the perception of acidity. This article breaks down six common causes one by one to help you determine whether the sourness in your cup is a flavor note or a defect. If you're looking for beans with balanced acidity and consistent quality, Front Street Coffee's range of espresso and pour-over beans may offer you a more controllable experience. [more…]

Is the acidity in coffee a plus or a minus? It depends on the quality of the acidity, not its intensity. This article approaches the topic from a cupping perspective, explaining the difference between acidity and acid quality, showing how coffee acidity is influenced by variety, altitude, processing method, and roast level, and revealing the relationship between fruity flavors and the balance of sweetness and acidity. At the same time, it recommends acidic coffee beans categorized by acid quality type: bright citrusy washed high-altitude light roasts, juicy full-bodied dark berry notes, and high-sweetness sun-dried beans blended with tropical fruit notes, helping coffee lovers choose beans precisely according to their preferences. [more…]

Americano coffee is deeply associated with a bitter, full-bodied impression, but many people feel puzzled when they drink an Americano with a sour taste: is this normal? In fact, coffee beans naturally contain abundant acidity, and both roasting and extraction methods affect the final flavor expression. This article will start with the sources of sourness and the dissolution order of bitter, sweet, and sour compounds, then systematically sort out practical methods for adjusting coffee that is too sour, including key points such as choosing the roast level, controlling water temperature, grind size, coffee-to-water ratio, and extraction time. At the same time, it will introduce the currently popular SOE Americano trend and share several Front Street Coffee espresso blends suitable for making Americanos, along with their brewing suggestions. [more…]

Jasmine Naibai recently launched a floral special blend "Green Mango and Wampee Iced Tea" that combines Hainan green mango, Guangxi wampee, and Yunnan sour papaya, highlighting a sweet-and-sour, refreshing taste. Each of the three sour fruits has its own character, making many sour-loving consumers eager to try it. However, after the new product launched, reviews have been polarized: some praise its tangy, refreshing quality that cuts through greasiness, while others report tasting a fishy note similar to houttuynia or fish mint. Interestingly, the netizens complaining about the fishy taste mostly come from the north, while staff and some consumers point the finger at the herbal note naturally present in Guangxi wampee. So how does this new product actually taste? Let's take a look together. [more…]

Why is coffee sour? This question puzzles many friends who are new to specialty coffee. Actually, the answer isn't complicated: coffee beans themselves are rich in various sour-tasting compounds. Before the turn of the millennium, dark roasting was the mainstream—long roasting times broke down much of these sour compounds, and the bitter, charred flavors masked what remained, so people once believed coffee was only bitter, never sour. With the arrival of the specialty era, roast levels shifted from dark to light, and sourness was rediscovered. But stronger sourness isn't necessarily better—what we truly pursue is "acidity quality," not "acidity level." The quality of acidity is influenced by multiple factors: growing altitude, soil, processing, roasting, and brewing. This article, from Front Street's perspective, will systematically sort out the origins and logic of coffee sourness and how to judge its quality. [more…]

The update to the coffee flavor wheel has made the tasting system more complete, but many people still feel confused when faced with descriptions like citrus, berries, and nuts. In daily brewing, Front Street Coffee recommends beans from different regions based on guests' taste preferences, while accurately identifying flavors requires systematic training. This article starts with the four major taste spectrums—sour, sweet, bitter, and salty—and, combined with the complete classification of the new flavor wheel, interprets one by one the specific expressions of floral, fruity, herbal, nutty and cacao, sweet, spice, sour and fermented, alcoholic fermentation, roasted, and other categories, helping coffee enthusiasts build a clear framework for flavor perception. [more…]

Many coffee enthusiasts notice that certain coffees seem to become more sour after they cool down. But this is not a universal trait of all coffee—most coffees simply lose some aroma as they cool, without their flavor framework shifting dramatically, and some even reveal greater sweetness as the temperature drops. So why does the sourness of certain coffees rise noticeably after the temperature falls? Behind this lies both the way human perception changes with temperature and the flavor composition of the coffee itself. From the perspective of Front Street, this article sorts out how temperature affects the perception of sourness, sweetness, and bitterness, explains the principle behind the intensified sourness of light-roasted coffee after cooling, and offers directions for adjustment when coffee is too sour. [more…]

Many friends who are new to specialty coffee often wonder: if coffee tastes sour, has it gone bad? In fact, sourness is not synonymous with spoilage, but rather a highly prized flavor dimension in specialty coffee. Drawing on the practical experience of Front Street Coffee, this article systematically sorts out the sources of coffee acidity, distinguishes good acidity from bad, and analyzes how factors such as roast level, grind size, water temperature, and brewing time affect the expression of acidity. At the same time, the article also introduces several African-origin coffee beans known for their bright fruity acidity, helping readers build a correct understanding of coffee sourness and stop confusing acidity with spoilage. [more…]

Recently, a meme about iced Americano has been trending on Douyin, inspiring many people to walk into cafés and try this drink. However, some have noticed that the iced Americano they get has a sour taste, which is quite different from the rich, bitter flavor they remember from Starbucks. In fact, a citrus or berry-like acidity in iced Americano is perfectly normal, as long as it isn't a rancid or harshly astringent sourness. Different cafés use different espresso beans: light-roasted single-origin beans have a more pronounced acidity, while dark-roasted blends lean toward a solid, bitter finish. This article will analyze the sources of acidity and bitterness in iced Americano from the perspectives of roast level and origin blending, introduce Front Street Coffee's approach to crafting it, and finally discuss the life philosophy behind this drink. [more…]

Many coffee enthusiasts have wondered: when Americano tastes sour, does it mean the beans are spoiled or have been sitting too long? In fact, for black coffees like Americano, pour-over, and cold brew, perceiving acidity is often perfectly normal. Starting from the daily offerings at Front Street Coffee, this article sorts out the major sources of acidity in Americano—including the choice of roast level, the fruity acidity inherent in the coffee beans themselves, possible channeling and grind inconsistencies during extraction, and the pattern of increased perceived acidity as the coffee cools—to help you determine whether a sour Americano is a flavor characteristic or a quality problem. [more…]

Americano may have already become the mainstream choice in coffee shops. Especially in summer, a glass of iced Americano is definitely a refreshing treat. Coffee has become a daily habit for many people—sometimes it's about enjoying the slow moments of life, and sometimes it's about adding a boost of mental energy to a疲惫 life of day-night reversal. No [more…]

Many coffee enthusiasts encounter a phenomenon when tasting pour-over coffee: as the temperature drops, the flavor of the coffee seems to change, sometimes even developing an unpleasant sourness. This is not a problem with brewing technique, but rather a series of physical and chemical changes that coffee undergoes as it goes from hot to cold. Front Street Coffee will take you on an in-depth look at the processes of aroma loss, oil oxidation, pigment polymerization, and condensation after coffee cools, while also explaining from the perspective of sensory science why the perception of sourness, sweetness, and bitterness on the taste buds changes with temperature. Through this article, you will understand the real reasons why coffee becomes sour or bitter after it cools, allowing you to view the relationship between coffee temperature and flavor more rationally and improve your tasting experience. [more…]

Pour-over coffee tasting too sour is a common problem encountered by many enthusiasts. This article starts from a real case—a customer brewed Yirgacheffe with 86℃ water and ended up with a sharp sourness, while Front Street Coffee's version was balanced and smooth—and takes a deep dive into how water temperature affects extraction: the higher the temperature, the more substances are extracted and the more the coffee leans sweet and bitter; the lower the temperature, the less is extracted and the more pronounced the sourness. The article points out that when brewing light-roasted beans such as Front Street Coffee's Yirgacheffe, a water temperature of 91℃ is usually recommended. In addition, it explores whether it is normal for fresh coffee beans to have a sour taste, and offers practical adjustment ideas to help you find the brewing parameters that suit you. [more…]

Many people, upon tasting an Americano with a sour note for the first time, instinctively wonder whether the beans have gone bad or been sitting around too long. In fact, green coffee beans naturally contain a large amount of organic acids, and after roasting, the acidity gradually decreases as the roast gets darker, so an Americano with a tangy taste can very well be a normal expression. However, not all sourness is worth appreciating—bright, lively fruit acidity can make a cup of coffee memorable, while sharp, astringent sourness often points to improper roasting or extraction errors. This article begins with the concept and characteristics of SOE, explains why Americano tastes sour, why iced and hot Americanos differ in acidity, and why a light-roast bean that shines in pour-over may not be suitable for espresso, and offers recommendations for blend beans suited to espresso. [more…]

Many coffee enthusiasts enjoy a well-balanced pour-over in cafés, with its harmonious blend of acidity and sweetness, yet when they brew at home, they often end up with a sharp, jarring sourness that leaves them puzzled. In reality, the flavor of coffee depends on the proportions of three types of substances: acids, sugars, and bitters. Sharp sourness is often a sign of imbalance—it’s not necessarily that there are too many acidic compounds, but rather that not enough sweet and bitter substances have been extracted. Front Street Coffee will take a deep dive into the principles behind sharp sourness and, from three angles—lowering the coffee-to-water ratio, extending the extraction time, and raising the water temperature—provide concrete, actionable adjustments to help you brew a smooth, mellow pour-over at home. [more…]

What exactly determines whether coffee is sour or bitter? Many people think that Ethiopian beans tend to be sour and Mandheling tends to be bitter because of their origin, but the real dominant factor is actually the roast level. This article starts with the development phase after first crack and explains how the length of the development phase affects the caramelization reaction, thereby determining whether the coffee's flavor leans sour or bitter. At the same time, using Kenya, Blue Mountain, and Mandheling as examples, it explains that dark roasting is not a cover-up for poor quality—sweetness within bitterness and a rich, balanced cup are what these classic beans insist on. Front Street Coffee also shares related insights in the article. [more…]