April 21, 2024 3 min read

What Makes a Great Cup?

At Harbinger, we pride ourselves on our daily application of scientific principles that make for outstanding coffee drinks. Understanding the science behind a great cup of coffee can help improve your own brew at home, choose better coffee when you’re out, and offers insight into why good coffee tastes the way it does. With coffee, a little bit of applied science goes a long way.




Water for coffee should be soft, with a balanced mineral content. Avoid distilled or overly hard water. For brewing, water should be brought to a temperature between 195° and 205°F. The right temperature is crucial for extracting the full flavor spectrum without adding bitterness.


The choice of green coffee beans (or seeds) is fundamental. Look for seeds with a high altitude origin, as they tend to have a more complex flavor profile. The seeds’ processing method—whether washed, natural, or honey-processed—also influences the final taste.



Roasting is where beans acquire their distinct flavors. It is typically done between 370 and 540 degrees, depending on the coffee type and desired roast. Lighter roasts retain the seeds’ inherent flavor profile, while medium and dark roasts develop deeper, caramelized flavors. Heat during roasting facilitates the Malliard reaction, which causes browning and allows for sweetness and richness to be developed in the coffee’s flavor profile.

Properly roasted coffee seeds are typically matte brown in color, which will be shaded darker or lighter depending on the roast level. Roasting too long or too hot will release oils from inside of the cellular structure of the coffee, causing the seeds to appear black and shiny. Coffee with this appearance tends to have a more bitter and burnt taste than coffee that has been roasted with more precision and care.


Grinding coffee is a critical step in preparing for brewing. The size of the coffee particles can significantly impact the taste of the final brew. The key is to match the particle size to the chosen brewing method, and have the particle size be uniform for even flavor extraction.

Espresso machines call for finer grounds, as hot water is forced through the tightly packed grounds under high pressure for a short duration. This fine grind allows for a quick, yet thorough extraction, resulting in the rich and concentrated flavor of espresso.

For drip or pour-over coffee makers, a medium grind works best. This size allows for a balanced extraction over a few minutes, ensuring that the water isn’t rushing through too quickly or draining too slowly. Coarse grinds are best suited for French press or cold brew methods, where coffee grounds steep in water for several minutes. The larger size of the grounds ensures that the coffee won’t over-extract, which can lead to bitterness.

Uniformity in grind size is crucial for balanced extraction; inconsistent grinds can lead to uneven extraction, where some coffee particles are over-extracted and others under-extracted, resulting in an imbalanced brew.


Proper coffee brewing requires the correct coffee-to-water ratio and brewing time. Pour-over requires a slow, steady pour to evenly extract the flavors, whereas espresso relies on high pressure for a quick, intense extraction.

Expert Tips

  • Pre-wetting the grounds can enhance flavor extraction.
  • Maintaining clean equipment is essential for consistent taste.
  • Experimenting with brewing times and temperatures can fine-tune your coffee's flavor profile.

Get the Perfect Brew At Harbinger

Harbinger Coffee exemplifies the synthesis of scientific precision and artistic flair. With years of experience and a passion for quality, Harbinger’s baristas apply these principles to deliver an exceptional coffee experience, making it a go-to destination for coffee lovers in northern Colorado.