Search Results for: residue
Why "season" the grinder before grinding for pour-over coffee? Analyzing the impact of grinder residue on flavor and key cleaning points
Many coffee enthusiasts, before brewing pour-over coffee, hear experienced baristas emphasize the step of "seasoning the grinder." But seasoning actually comes in two forms: one is the daily deep cleaning of the grinder, and the other is the "pre-grinding" done before each grind. The two serve different purposes and should not be confused. This article explains in detail why a small amount of beans from the same batch should be used to season the grinder before grinding coffee beans, how residual coffee powder and burr oils affect the flavor of the next cup, and why an air blower cannot replace bean seasoning. At the same time, Front Street Coffee will also offer recommendations on the amount of beans to use for seasoning, helping you present the true flavor of each bean in a purer way. [more…]
Complete Guide to Espresso Machine Backflushing: Water and Detergent Steps and Recommended Frequency
You dialed in your espresso extraction parameters in the morning, but by noon the flow has slowed and become unstable? Besides changes in humidity and switching beans, coffee residue built up inside the group head is often the culprit. Backflushing is the key method for removing this residue—using a blind basket to force water to flow backward through the lines, then combining it with cleaning powder to deep-clean stubborn coffee grime. This article explains in detail the procedures for water backflushing and cleaning-powder backflushing, the number of repetitions, and the daily maintenance frequency, helping baristas maintain stable extraction and avoid off-flavors getting into the cup. [more…]
Starbucks Salted Flat White Leaves Black Powder Residue at the Bottom of the Cup, Staff Clarifies: Having Powder Is the Standard Serving
Starbucks has clearly picked up the pace of new product launches this year. Before people have even had a chance to check in on the cherry blossom limited edition, the Salted Flat White has already taken over as the store's main promotion. However, this new product has sparked controversy because of black powder residue left at the bottom of the cup, with many consumers suspecting that staff had made an operational error and mixed in coffee grounds. Faced with complaints, Starbucks staff collectively protested their innocence—having coffee powder is actually the correct method, and not having it would instead be a violation. What exactly is going on here? Why is the freshly ground coffee powder used for decoration so often mistaken for extraction residue? And why do consumers have so many complaints about the taste? This article will reconstruct the whole incident and analyze the gap between the standard recipe for this beverage and the consumer experience. [more…]
Espresso Machine Cleaning Guide | How Often Should an Espresso Machine Usually Be Cleaned? What Are the Steps to Clean a Semi-Automatic Espresso Machine at Home?
I believe baristas must have encountered this problem: in the morning, the espresso extraction parameters are dialed in, but by noon, the parameters are no longer accurate, and the coffee flow rate has noticeably slowed down. Front Street has previously offered explanations for two scenarios regarding this issue. The first is when it rains and the humidity in the air is relatively high, inside the bean hopper. [more…]
The Controversy Over Nayuki's Little Red Bottle Fruit Pulp: Freshly Squeezed Fruit Not Filtered—Selling Point or Drawback?
Nayuki recently launched a new product, the "Double-Antioxidant Little Red Bottle," featuring freshly squeezed Yunnan tree tomatoes paired with blueberries, cherry tomatoes, lemons, and other fresh fruits. It is advertised as sweet and tangy, rich in vitamin C and lycopene. However, not long after its release, the first wave of curious consumers began complaining: a large amount of fruit peel and seeds settles at the bottom of the cup, and one sip fills your mouth with grit—some people even nearly choked on a lemon seed. Staff responded that filtering the fruit puree was not required during preparation, and the final product varies due to differences in technique. Interestingly, netizens are divided on the issue—some suggest adding a filtration step, while others believe the fruit residue is precisely proof of "genuine ingredients." Behind this controversy lies the challenge of balancing taste and health in fruit-and-vegetable teas. [more…]
Mushroom Residue Found at the Bottom of a Tims Coffee Cup, Food Safety Controversy at Canadian Stores Escalates Again
Drinking a cup of coffee all the way down, only to find mushroom residue at the bottom of the cup—this is not a joke, but a real incident that recently occurred at a Tims store in Markham, Ontario, Canada. After the consumer posted the experience on social media, it quickly sparked heated discussion, with many netizens saying it was deeply disturbing. In fact, this is not the first time Tims in Canada has been in the spotlight over food safety issues. From moldy products to a fly found in coffee, to employees collecting saliva in coffee cups, various outrageous actions keep refreshing consumers' perceptions. At the same time, controversy over Tims' internal employee recruitment has also surfaced. A white woman who worked there for four years was fired after accusing management of hiring only Indian immigrants, and the post received over 4.2 million views. Front Street Coffee continues to follow developments in the coffee industry, and this article will take you through the full picture of the incident. [more…]
Uncovering the Hidden Factors Behind Unstable Espresso Extraction: How Residual Grounds, Water Temperature, Pressure, Environment, and Chamber Pressure Affect the Flow
Many coffee enthusiasts will notice that with the same beans and the same machine, the flow rate of espresso can change every few hours or even every few dozen minutes, sometimes fast and sometimes slow. Beyond the aging characteristics of the coffee beans themselves, there are actually quite a few easily overlooked hidden factors influencing the extraction results, including residual grounds in the grinder's chute, temperature fluctuations in the espresso machine's hot water, the state of the pump pressure, changes in ambient temperature, humidity and air pressure, and whether the grinder's hopper pressure remains stable in a café setting. Front Street will analyze these factors' mechanisms of influence on espresso extraction one by one, and provide corresponding improvement solutions to help everyone reduce unnecessary adjustments and make their output more consistent. [more…]
Why Does Plain Water Taste Sweet After Coffee? Exploring the Relationship Between Sweet Aftertaste, Oil Residue, and Taste Sensitivity
Many people, after finishing a cup of coffee and then taking a sip of plain water, are surprised to find that the water actually tastes sweet. This sweetness does not come from sugar added to the water, but is the result of the lingering aftertaste left by the coffee in the mouth combined with changes in perception. Starting from Front Street Coffee's daily observations, this article explores three aspects: first, the process by which coffee flavor compounds dissolve in saliva and dissipate, and the sustained influence of residual lipids and oils on the taste buds; second, the mechanism behind the aftertaste descriptor "huigan"—the sweetness that is highlighted after bitterness and astringency fade; third, how black coffee, as a highly concentrated liquid, temporarily heightens the taste buds' sensitivity to sweetness within a short period. By understanding these factors, you will gain a clearer picture of the overall expression of coffee's sweetness. [more…]
Why Discard the First Espresso Shot from an Espresso Machine? A Full Breakdown of Cleaning, Preheating, and Operation at Home and in Cafés
Many coffee enthusiasts have noticed that after switching on, coffee shops often pour away the first espresso pulled before they begin serving drinks as normal. Behind this seemingly wasteful gesture are actually multiple considerations, including cleaning powder residue, overnight coffee grounds, and machine parameters that have not yet stabilized. But for home users who only make one or two cups a day, is it necessary to copy this practice? Starting from the actual operating habits of Front Street stores, this article systematically sorts out the reasons why the first espresso is discarded, and offers specific advice for home scenarios on whether it needs to be poured out, how to properly handle residual grounds, and how to effectively preheat the coffee machine after deep cleaning, helping you ensure stable flavor in every cup while reducing waste. [more…]
Complete Guide to Cleaning and Maintaining Manual and Electric Coffee Grinders: Brush Cleaning and Deep Maintenance Essentials
Coffee grinding equipment is mainly divided into two categories: manual and electric. Different brands and price points not only affect appearance and grinding performance, but also determine differences in burr structure and particle size distribution. Regardless of which grinder you use, daily cleaning and regular maintenance of the burrs are key to extending the life of the equipment. The static electricity generated during grinding causes fine particles to stick to the metal burrs and the grounds bin. The more frequently it is used, the more residual grounds accumulate, and the oil released by dark-roasted beans worsens the buildup of oily residue. If not cleaned for a long time, old grounds not only produce a rancid oil smell, but also taint new grounds and clog the grinding path. This article will introduce grinder maintenance methods and precautions in detail across three levels: daily quick cleaning, cleaning without disassembly, and regular deep cleaning. [more…]
Where Do Cold Brew Coffee Oil and Fine Particle Residue Come From? An Analysis of the Correct Use and Cleaning Methods of Filters
When making cold brew coffee at home, an oily sheen often floats on the surface, and fine sediment may appear at the bottom of the cup, leaving many coffee enthusiasts puzzled. What exactly are these floating substances? Is the coffee spoiled, or is the equipment unclean? In fact, this is closely related to the slow release of water-soluble fats from coffee beans at low temperatures. This article, drawing on Front Street Coffee's practical experience, analyzes the causes of cold brew oils, explains how the differences in mesh sizes of various filtering devices affect coffee flavor, and shares how to use secondary filtration with paper filters and refrigeration settling to make cold brew's juicy feel fuller and its acidity clearer. At the same time, regular deep cleaning of equipment is equally crucial to avoid the accumulation of condensed oil residue that produces a rancid odor. [more…]
Home Espresso Machine Maintenance Guide: Daily Cleaning, Deep Descaling, and Group Head Gasket Replacement Tips
Many coffee enthusiasts have added espresso machines to their homes, but due to a lack of knowledge about cleaning and maintenance, problems such as weakened steam, uneven water flow, and even portafilter leaks begin to appear after the machine has been used for a while. This article systematically organizes maintenance methods for home espresso machines: from the routine cleaning of the steam wand and shower screen after each brew, to using a blind basket to backflush and remove internal residue before shutting down, and then to regularly using specialized cleaning powder for deep treatment of the steam wand, shower screen, and portafilter basket. The article also explains in detail the steps for replacing the brew head gasket after it ages, and reminds readers that water needs to be filtered to prevent scale from damaging the boiler. The article involves practical experience with the machine models used in Front Street Coffee stores, and is suitable for coffee enthusiasts to follow and implement. [more…]
Coffee Machine Maintenance | How Should Coffee Beginners Clean and Maintain a Home Semi-Automatic Espresso Machine? How to Replace the Gasket on an Espresso Machine?
For professional coffee knowledge exchange and more coffee bean information, please follow Coffee Studio (WeChat official account: cafe_style). For more specialty coffee beans, please add our private WeChat: Front Street Coffee (FrontStreet Coffee), WeChat ID: qjcoffeex. With the rise of specialty coffee culture [more…]
Analysis and Solutions for Residual Water in the Portafilter Basket After Espresso Extraction
After pulling an espresso shot, the ideal puck should be dry, intact, and come out in one solid piece without crumbling. But in practice, many coffee lovers run into a soggy, muddy puck with standing water at the bottom of the basket. This abnormal phenomenon is usually linked to four factors: grinding too fine, coffee beans stored too long so they lose carbon dioxide, too large a gap between the puck and the dispersion screen, and unstable extraction pressure in the espresso machine. This article breaks down the principle behind each cause one by one and offers corresponding troubleshooting and adjustment methods to help you quickly pinpoint the problem and get back to normal extraction. [more…]
Coffee Flavor Tasting | Can drinking ice water before drinking pour-over coffee help you taste more flavors? What role does ice water play in the coffee tasting process?
"By rinsing our mouths with ice water, we can better appreciate a cup of coffee and more easily capture its delicate flavors." This is a saying that has long circulated in the community. That's why we often see customers in cafés, after ordering their coffee, ask the barista for a cup of ice water, and their main purpose is precisely this. [more…]
Why Drink Iced Water Before Coffee Tasting? The Origins of Espresso with Iced Water and an Analysis of Its Applicability to Pour-Over
When ordering at a café, you'll often see a glass of ice water served alongside an espresso, and many enthusiasts are in the habit of drinking ice water before their coffee. Can this glass of ice water actually help us perceive coffee flavors more clearly? Front Street Coffee will approach this from the perspective of oral sensory cleansing, explaining how ice water enhances the tasting experience by rinsing away residue, stimulating saliva production, and numbing the palate through low temperature, while also tracing the origins of this practice in espresso culture. It will also discuss whether pour-over coffee is suited to the same approach, and why room-temperature water is gentler on the stomach and intestines. [more…]
A Complete Guide to Costa Rican Honey-Processed Coffee: Flavor Differences Between White, Yellow, Red, and Black Honey
Costa Rica is famous for its extremely pure, soft, and balanced coffee style, and the introduction of the honey process has added richer body and sweeter layers to this producing region. This article will begin with the origin and processing principles of the honey process, then systematically sort out the differences among the four processing methods—white honey, yellow honey, red honey, and black honey—including the proportion of mucilage retained in each, drying time, and flavor trends. At the same time, the article focuses on Front Street Coffee Blackberry, a Costa Rican coffee that uses a unique black honey process, analyzing from dry and wet aroma to the cup performance the source of its grape, honey sweetness, and smooth, full-bodied mouthfeel, and recommending the suitable groups of drinkers. [more…]
A Detailed Guide to Backflushing the Group Head of a Semi-Automatic Espresso Machine and Daily Maintenance Methods
The espresso machine is the core equipment of a coffee shop. Regular cleaning not only extends the machine's lifespan but also ensures the consistency of every cup produced. This article focuses on the key step of cleaning the interior of the group head, explaining in detail the specific procedures for quick cleaning, daily backflushing, and long-term maintenance. From judging residue on the dispersion screen to the backflush process using a blind basket with cleaning powder, and then to soaking the portafilter to remove oils, each step has clear requirements for timing and frequency. At the end, it also reminds readers that professional deep maintenance is needed every 1–2 years, making this a worthwhile reference for both coffee enthusiasts and industry professionals. [more…]
How Is Decaf Coffee Decaffeinated? Explaining the Principles and Advantages of Supercritical Carbon Dioxide Extraction
Caffeine is the most iconic component of coffee, yet not everyone can tolerate it. It is both the primary source of bitterness and a neurostimulant that affects sleep. Thus, decaffeinated coffee was created to remove caffeine. However, the challenge of decaffeination lies in how to remove only the caffeine while preserving the aroma and flavor of coffee as much as possible. Early methods using organic solvents were effective, but left consumers concerned about residues. It was not until the advent of supercritical carbon dioxide extraction technology that a truly efficient and highly selective decaffeination process was achieved. This article will guide you through the principles of this technology, its development history, and its unique advantages in coffee decaffeination, while also introducing Front Street Coffee's attention to and practice of this process. [more…]
Exploring Silver Skin Flavor in Coffee Beans: What Real Impact Do Residual Flecks Have on Coffee Taste?
When grinding coffee beans, you will often find yellowish-white flakes mixed in with the grounds—these are the silver skin of the coffee bean. The silver skin is the last natural layer wrapping the green bean before roasting, and how much of it remains varies by processing method: naturally processed beans shed their silver skin relatively completely, while washed beans tend to leave an obvious white line at the center of the bean. Many coffee lovers wonder: do these silver skin flakes interfere with the flavor of the coffee? The roasters at Front Street Coffee designed a set of experiments specifically for this, extracting silver skin by three methods—pour-over, tea bags, and espresso machine—to verify its actual impact through taste performance. This article will walk you through the structural characteristics of silver skin, the differences in how much remains under different processing methods, and the flavor conclusions drawn from the experiments. [more…]