Introduction:This article documents an actual pour over experiment, recording how coffee beans from Papua New Guinea’s Chimbu region perform at different roast levels. From over-extraction leading to flavor loss to mastering the roast to bring out sweet fruitiness and aftertaste, it details key extraction parameters such as water temperature, brew ratio, and bloom time, helping you understand how the roast profile can change the flavor profile of a cup of pour over coffee.
Although geographically relatively remote, Papua New Guinea (PNG) is one of the specialty coffee industry’s notable origins. This island nation in the southwest Pacific, with its highland environment and unique microclimates, has produced many representative coffee varieties, and the Chimbu region is one of its rising stars. This article records two pour over roast experiments conducted by the author on coffee beans from the Chimbu region. By adjusting roast time and heat, it observes their impact on the final flavor expression.
The first attempt, due to not mastering the roast rhythm well, did not drop the beans promptly after the first crack, allowing them to enter the second crack stage. Although the beans looked uniformly colored and oily, their performance in pour over was not as expected. Using a water temperature of 90°C,a brew ratio of 1:12 (10 grams of coffee grounds to 120 milliliters of water), and starting extraction with a 40-second bloom , the result was a coffee that, while full-bodied and with a long aftertaste, lacked the expected fruity aroma and bright acidity. The overall impression was heavy, with a rather single-layered flavor profile.
The second time, the strategy was adjusted to focus on capturing the flavor potential during the first crack dense phase. When the first bean cracking sound was heard, followed by continuous and dense cracks within one minute, this is what is called the "first crack dense phase." This time, the author dropped the beans about 10 seconds after the first crack sound, preserving more of the beans’ sugar compounds and fruity precursor substances. The resting time was shortened to 48 hours, and the pour over ratio was changed to 1:15 (10 grams of grounds to 150 milliliters of water), still using 90°C water temperature and a 40-second bloom. The outcome this time was surprising: the coffee had a noticeable sweetness upon entry, and although the fruit acidity was not prominent, the overall balance was good, with a clean and lasting finish. Particularly, the aroma displayed rich tropical fruit and honey notes in the mouth, clearly more appealing than the first attempt.
These two experiments clearly show that the degree of roasting has a decisive influence on the flavor direction of pour over coffee. Over-roasting tends to make coffee lose its delicate acidity and fruitiness, instead exhibiting excessive caramelization and bitterness; whereas dropping the beans at the right time during the first crack dense phase helps retain more floral and fruity tones along with sweetness, giving the coffee more layers and drinking enjoyment.
In addition, the setting of pour over parameters is equally critical. For example,90°C is a common water temperature suitable for medium-light roasted coffee, effectively bringing out a balance of acidity and sweetness along with aroma; while the brew ratio affects intensity and flavor expression— the higher the ratio, the lighter the taste, but if the beans themselves have restrained flavors, the water amount can be moderately increased to bring out their potential. The bloom stage is recommended to be at least 30–40 seconds, which helps activate the coffee grounds and improve overall extraction uniformity.
For coffee enthusiasts who enjoy trying different origins and processing methods, Papua New Guinea Chimbu coffee beans are a worthy option for deeper exploration. Its honey processing method, combined with high altitude and good agronomic management, gives the coffee a rich and full-bodied base. With appropriate roasting and pour over extraction, it can even more release enchanting sweetness and aftertaste, suitable for drinkers who pursue low acidity and emphasize flavor balance.
The above content is compiled by CoffeeHunters, a coffee news website.
