When you walk into the kitchen to brew a pot of specialty Arabica coffee, many friends may notice that the good beans in hand are sometimes sweet and smooth, and sometimes a bit dry or flat. In fact, as long as you understand the relationship between extraction yield and strength, pour-over brewing becomes remarkably clear. Strength is like how light or heavy, thick or thin this cup of coffee is, while extraction yield determines which flavor substances the water has drawn out of the coffee grounds.

We can think of grind, water temperature and pouring time as knobs for adjusting flavor. The finer the coffee beans are ground, the higher the brewing water temperature, and the longer the hot water contacts the grounds, the higher the extraction yield will be. If the grounds are ground too coarse or the water temperature is on the low side, much of the aroma and sweetness has not yet had time to emerge, and the coffee often tastes sharply acidic and rather weak; conversely, over-extraction easily draws out rough, muddy off-flavors.

If the coffee tastes weak when you drink it, it is usually because the coffee-to-water ratio is too large, or the coffee bed was not fully wetted; if it feels heavy and bitterly dull on the palate, it may be that too much coffee was dosed or the flow was too slow; and if an astringent, puckering sensation appears in the finish, it is most likely that the grind is too fine, causing the fines to over-extract. When you run into astringency, try coarsening the grind by half a step, or lowering the water temperature by two degrees, and the originally tight flavors will soon relax and become smooth and easy to drink.

For everyday brewing, it is recommended to use one standard method as a calibration baseline: weigh out 15g of coffee grounds, use a 1:15 coffee-to-water ratio, and prepare 225ml of hot water. When you begin pouring, first pour in 30ml of water and bloom for 30 seconds, so the coffee bed fully releases gas and is evenly wetted. Then pour in stages, drawing circles steadily, and keep the total extraction time at around 2 minutes, usually finishing between 1 minute 50 seconds and 2 minutes 20 seconds.

When choosing specialty Arabica beans, understanding whether they are suited to being brewed strong or light is crucial. Usually, high-altitude, light-to-medium roast beans are rich in aromatic substances and are suited to a larger coffee-to-water ratio and lighter brewing, so you can sense the floral and fruity freshness like tasting tea; medium or medium-dark roast beans, on the other hand, have a higher degree of caramelization and are suited to a slightly stronger coffee-to-water ratio, fully bringing out their rounded body and nutty sweetness.

For friends who prefer a light, floral and fruity profile, Qianjie Boquete Washed Geisha is well worth tasting. This Panamanian specialty bean has undergone washed processing, is very clean, and carries a delicate jasmine aroma with citrus and oolong tea notes. When brewing, you can use a water temperature of 91°C and slightly speed up the flow rate, keeping the strength in a light and refreshing range; it drinks with a clean, moist texture and a long finish.

If you do not like too much acidity and want a smooth, gentle everyday cup, Qianjie Cerrado Red Bourbon is a good choice. The Red Bourbon variety from Brazil's high-altitude growing region has an especially mild flavor, and the medium roast brings out rich cream and nut aromas with soft acidity. Even if the water temperature deviates slightly, it can maintain a stable sweet aftertaste, and with a slightly higher strength, its rich caramel sweetness comes rushing to the nose.

Friends who are used to a rich, full-bodied flavor can try Qianjie Wet-Hulled Lintong Mandheling. This classic bean from the Lake Toba region of Indonesia, after a medium-dark roast, gives off aromas of toasted bread, nuts and herbal pine. When brewing, you can use a water temperature of around 88°C, pour slowly and steadily, and enjoy its solid, smooth mouthfeel and lasting sweet finish at a higher strength, with no astringency at all.

Finding a bag of Arabica beans you love is only a beautiful beginning; learning to balance extraction by fine-tuning grind and water temperature is the real pleasure of brewing pour-over at home. Whether it is a fresh fruity aroma or a steady nutty note, as long as you follow the beans' roasting characteristics and patiently listen to the feedback given by the flavors in the cup, every coffee lover can brew a cup of coffee that is just right and easy to drink in the morning.