In Fetco‘s first foray into “Brewing Sessions” podcast, they explain the 6 basic elements that can affect coffee taste: brewing temperature, formula of water-to-coffee, contact time, grind particle size, turbulence and freshness after brewing.
Temperature: Matt Greg, a regional sales manager with Fetco, explains that coffee should be brewed at 195-200F – generally toward the low end for high altitudes, toward 200F for more moderate altitudes. If you brew at too high of a temperature, the water elements from the coffee that will cause a tinny, metallic taste. At too low a temperature, not enough flavors will be extracted from the coffee to achieve a good coffee taste.
Formula of Water-to-Coffee: The next most important step after finding the correct brewing temperature is deciding the right amount of your coffee to use when brewing. As a general rule, you want to use 3.25-4.25 oz. of coffee per 64 oz. of water. The key is to find a good balance for the particular coffee you are brewing – too little coffee and you will emphasize the low, smoky, bitter elements of the bean; too much coffee and you will highlight mostly citrus and acidic tones. The perfect formula will balance the flavors and give you a rich, balanced cup.
Contact Time: The contact time begins with the spray-over time and ends when the coffee exits the brew basket. An optimal contact time extracts a balance of flavors from the coffee, and it depends on size of batch and kind of coffee you are brewing.
Grind Particle Size: A larger particle takes longer to break down than a smaller particle, plus the water will pass through larger grinds faster without extracting as many flavors. With too small a grind, the water will pass through the entire ground too easily, and can pick up too many undesirable flavors. The larger the batch size you are brewing, the larger the grind size you want, otherwise, the water will extract too many flavors from the bean
Turbulence: The churning motion that occurs in the brew basket. The more churning, the more flavors absorbed by the water.
Freshness after Brewing: After about 20 minutes, coffee sitting on a burner will start to break down and affect flavor – the oils become more rancid and bitter. Thermal servers can alleviate this problem, but coffee can even continue to cook in a thermal server. If is best to keep coffee in a thermal server and use it within a couple of hours.
A great podcast – hopefully the first of many.