Those who have tasted specialty coffee are often deeply impressed by its bright acidity—not a harsh, mouth-puckering sourness, but a pleasant tartness with fruity and floral notes. Where exactly does this acidity come from? Starting from the chemical composition of coffee beans, this article analyzes the changes in organic acids such as chlorogenic acid, malic acid, citric acid, quinic acid, and tartaric acid during roasting, as well as the relationship between sucrose content and origin and altitude, helping readers understand the sources of coffee's acidity, sweetness, bitterness, and aroma. Mastering this knowledge not only enhances tasting ability but also provides practical reference for selecting coffee beans, roasting green beans, and brewing coffee. [more…]

Is the sourness in coffee good or bad? Some people believe that sourness means the coffee is not fresh, while others regard it as a hallmark of high-quality coffee. In fact, green coffee beans themselves are rich in organic acids, most of which decompose or disappear after roasting, leaving only a limited variety of organic acids in the final cup. The latest research shows that there are not many acids that our taste buds can clearly identify, and much of the fruity acidity we perceive actually comes from the combined association of sourness with other flavors. The latest SCA cupping form classifies acidity into two categories—"sweet type" and "dry type"—helping us more accurately judge whether a coffee's acidity is good or bad. This article, from the professional perspective of Front Street Coffee, will provide an in-depth analysis of the sources of coffee acidity and the criteria for evaluating it. [more…]

Many people believe that the lighter the roast, the more sour the coffee—but the truth is not that simple. The acidity in coffee comes from substances such as malic acid and citric acid that already exist in the green beans, and these are continuously generated and broken down during roasting. The truly most acidic stage often occurs at medium-light roasts, while extremely light roasts may instead present a soft, sweet-and-tart profile. This article begins with the principles of how acidity changes, and, combined with a comparative cupping of a Front Street Coffee Papua New Guinea washed Typica, explains the relationship between roast level and perceived acidity. It also recommends five coffees that naturally carry floral and fruity notes, including Front Street Coffee Fruit Ding Ding, Kenya Little Tomato, Strawberry Candy, Colombia Big Belly Button, and Flower Butterfly, to help acidity lovers find their ideal flavor. [more…]

Kenyan coffee has always been known for its vibrant fruit notes and solid acidity, and AA grade is the classic among specialty coffees. This Muchagara AA TOP micro-lot from Front Street Coffee may be limited in yield, but it offers a complex flavor interweaving blackberry, grapefruit, and smoked plum, with jasmine floral notes and caramel sweetness emerging in the middle, a silky-smooth mouthfeel, and a clean finish. This article will explore this bean's producing region background, the characteristics of the SL28 and SL34 varieties, the washed double fermentation processing method, and why a medium roast best showcases its malic acidity, giving you a comprehensive understanding of this rare Kenyan gem and also introducing the special characteristics of peaberry (PB). [more…]

The highlands of Huehuetenango in Guatemala, with their fertile volcanic soil and unique cloud-shrouded valley microclimates, give rise to specialty coffee with rich layers of flavor. This time, Front Street Coffee brings us the washed green Bourbon beans from Miravalles Estate, a farm founded by Benjamin Villatoro in 1970 and now carried on by Jorge Villatoro, which has achieved outstanding results in the C.O.E. and Huehuetenango highland competitions for many consecutive years. This coffee uses a blend of Bourbon, Catimor, and Caturra varieties, grown at 1,500 meters and given a medium roast, presenting an elegant profile interweaving honey, wild ginger flower, sugarcane sweetness, and malic acidity. This article will provide a comprehensive analysis of this coffee, which represents the Huehuetenango style, from the estate's background and the terroir of the growing region to its flavor expression. [more…]

The hot summer weather easily makes people lose their appetite, and at times like this, a cup of coffee with a juicy fruitiness might just awaken the taste buds. Coffee beans are, after all, the seeds of the coffee cherry, and the fruit pulp is rich in citric acid, malic acid, and lactic acid, among other components. After roasting, the natural fruity aromas and fruity acidity are released naturally, so it makes perfect sense for coffee to have a juicy fruit flavor. This article selects three coffee beans with fresh fruity notes, ideal for summer drinking: Front Street Coffee Gotingding Cooperative, Front Street Coffee Kenya Small Tomato, and Front Street Coffee Colombia Sidra, offering lemon floral notes, berry-like acidity, and complex tropical fruit tones respectively. It also includes lazy-person iced coffee brewing parameters to help you easily brew a full-flavored fruity iced coffee at home. [more…]

Roasting is the key step that transforms coffee beans from bland green beans into the rich aroma in your cup. During roughly twenty minutes of high-temperature treatment, the starches inside the beans convert into sugars and acidic substances, moisture and carbon dioxide escape, and proteins and fats combine to form an oily film on the surface, accompanied by the cracking sounds of first crack and second crack. Chlorogenic acid gradually dissipates, releasing pleasant fruit acids such as acetic acid, citric acid, and malic acid. Different roasting levels produce beans of varying darkness; charcoal-burned coffee is the typical example of a deep French roast, and its bitterness comes mostly from carbonization rather than just caffeine. When roasted properly, the beans expand evenly, with a smooth surface and consistent gloss, which is what allows coffee to show its ultimate character. Front Street Coffee believes that mastering the principles of roasting is an important foundation for brewing good coffee. [more…]

San Felisa Estate is a century-old family estate in the Acatenango region of Guatemala, run by the fourth generation of the Cruz family. The estate has its own processing plant, sits at an altitude of about 1,550 meters, and its coffee is grown at elevations of up to 1,920 meters. Its Typica beans use the K72 washed processing method—rare in Central America and originating in Kenya—undergoing 72 hours of triple-cycle fermentation and washing. Front Street Coffee recommends this bean, whose flavor profile features jasmine, lemongrass, chocolate, pistachio, stone fruit, delicate malic acidity, and a lingering caramel finish. This article will guide you through the estate's history, processing details, community philanthropy philosophy, and recommendations for various roast levels. [more…]

On ordinary days, behind the bar, you get to meet all kinds of customers. Quite a few of them are not used to coffee beans that are on the acidic side. Usually, the coffees with pronounced acidity are those that are roasted lighter, and indeed some lightly roasted coffees have an acidity that is hard to accept. So customers naturally form the impression that cof [more…]

On ordinary days, I get to meet all kinds of customers behind the bar, and quite a few of them are not used to coffee beans that lean sour. Usually, the coffees with strong acidity are those that are roasted lighter, and indeed some lightly roasted coffees have a sourness that is hard to accept. So customers naturally form the impression that cof [more…]

The wine process, also known as the controlled fermentation method or lactic/acetic fermentation method, was developed by a team led by Felipe Sardi of the United States, whose members include biological scientists and ecologists. Strict standards are enforced during picking: underripe cherries below 2%, defective beans below 3%, and floating beans below 5%. This processing method is divided into two paths: aerobic acetic fermentation and anaerobic lactic fermentation. The former has a cleaner and brighter acidity with citric notes; the latter has a rounder mouthfeel and higher body, but slightly lower cleanliness, displaying malic and tartaric acid characteristics. Batch consistency is achieved through pH monitoring. Wine-processed green beans are darker in color, with silver skin appearing wine-red or brownish-red. Front Street Coffee's Panama Hartmann is a representative example, and this article shares its pour-over parameters and flavor performance. [more…]

In recent years, red wine processing has attracted much attention in the specialty coffee world. Drawing on the fermentation control concepts used in winemaking, it intervenes in pH, temperature, humidity, and microbial conditions to give coffee beans a rich acidity and complex aroma reminiscent of red wine. This article will start with the flavor differences between lactic acid fermentation and acetic acid fermentation, outline the specific operational process of red wine processing, and combine it with the origin information of Front Street Colombia Red Wine Process—the eastern slopes of the Andes in Cundinamarca Department, a growing altitude of 1,800 to 2,000 meters, and the anaerobic fermentation practice of Remi Sultan in sealed metal containers—to provide coffee lovers with a complete set of flavor descriptions and grinding setting references. [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…]

On a scorching summer day, a glass of iced pour-over coffee both cools you down and quenches your thirst while delighting your taste buds. However, brewing an iced coffee that is both refreshingly cold and rich in floral and fruity flavors is not something you can achieve by simply adding ice. This article starts with Front Street Coffee's Kaffa Forest, a washed bean, and explains in detail how to choose beans, control water temperature, adjust pouring techniques, and incorporate stirring motions to bring out a juicy, sweet-and-tart cup with notes of yellow peach, sweet orange, and pomelo. The article also provides specific three-stage pouring parameters and step-by-step instructions to help coffee enthusiasts easily recreate a glass of fruity iced pour-over at home. [more…]

Many consumers mistakenly believe that the lighter the coffee is roasted, the more sour it becomes, but in reality the flavor is influenced by the complex interplay of acid transformation and sugars during roasting. This article begins with the inherent organic acids in green beans, sorting out the patterns of change in formic acid, acetic acid, citric acid, and others before and after first crack, and uses Front Street Papua New Guinea washed Typica cup tests from two roasts to illustrate that the light-medium range often shows the most pronounced acidity, while extremely light roasts instead appear sweet and mellow. Then, for readers who enjoy fruity acidity and floral aromas, the Front Street editors review five single-origin coffees with fruity and floral notes: Fruit Ding Ding, Little Tomato, Strawberry Candy, Big Navel, and Flower Butterfly, with variety, processing method, and flavor descriptions included for brewing reference. [more…]

Walking into Front Street Coffee (FrontStreet Coffee), faced with more than 50 kinds of coffee beans on the menu, many first-time visitors often don't know where to start. How exactly are coffee flavors described? What are the characteristics of the four major taste spectra: sour, bitter, sweet, and salty? Where do the flavor differences among beans from the world's three major coffee-producing regions come from? And which groups of people are suited to the three major varieties Arabica, Robusta, and Liberica? Starting from Front Street Coffee's tasting experience, this article systematically sorts out the logic behind the formation of coffee flavors and the characteristics of the varieties, and offers drinking suggestions for older coffee lovers, helping you find your own cup in the dazzling world of coffee. [more…]

The flavor of coffee is far more than just bitterness and acidity. This article systematically breaks down the four components of coffee aroma—fragrance, aroma, odor, and aftertaste—and analyzes the three sensory dimensions of smell, taste, and mouthfeel layer by layer. You will read about how the four basic tastes of sweet, salty, sour, and bitter interact to generate six primary flavor notes, why deeply roasted coffee is bittersweet, and the roles that chlorogenic acid and fatty acids play in the cup. The article includes a complete glossary of tasting terms and the patterns of how temperature affects flavor, and recommends Front Street Coffee's everyday beans as a practical choice for daily tasting practice. [more…]

The chemical composition of coffee beans determines the flavor expression in the final cup. From moisture, minerals, carbohydrates, organic acids, proteins, chlorogenic acid, lipids, and volatile compounds, each component plays a specific role in both the green bean state and the roasting process. Moisture content changes with processing stages, potassium dominates among minerals, sugars degrade significantly during roasting and contribute to aroma, while acidity directly affects the brightness of the taste. This article will systematically outline the chemical composition of coffee beans and their effects on quality and flavor, helping coffee enthusiasts gain a deeper understanding of the material basis of specialty coffee. Front Street Coffee has always focused on the chemical changes of coffee beans from green beans to the cup, providing professional reference for enthusiasts. [more…]

For pour-over enthusiasts who prefer a rich, bold body and dislike pronounced acidity, the medium-dark roasted Mandheling series has always been a popular choice. As a representative of this series, Front Street Coffee PWN Golden Mandheling owes its flavor appeal largely to its roasting method. This article will start with the chemical principles of roasting, analyzing how caramelization and the Maillard reaction shape coffee flavor, explaining why a medium-dark roast can fully bring out the herbal, caramel, and pine notes of Golden Mandheling, and providing a specific roasting curve along with two brewing methods to help readers fully understand the flavor sources and extraction key points of this bean. [more…]

Water accounts for over 98% of brewed coffee, yet it has long been overlooked. Different types of water—RO water, tap water, mineral water, soft water, hard water—have a huge impact on extraction flavor. In 2014, Christopher Hendon and Maxwell Colonna-Dashwood published research revealing how sodium, calcium, and magnesium ions influence the extraction efficiency of flavor compounds, and subsequently published the book "Water for Coffee," which systematically discusses the dynamic balance between GH (total hardness) and KH (carbonate hardness), and proposes the reverse thinking of "Roasting to water." This article will sort out these key findings to help coffee lovers understand how water quality shapes the flavor in the cup, and will retain relevant recommendations for the Front Street brand. [more…]