Bean to brew: coffee study examines aromatics
Tuesday, May 11, 2010
As any caffeine connoisseur will attest, if a coffee bean is prepared correctly, its aromatics can delight the senses and tickle the taste buds. However, if the beans are too burned, they can impact the taste of the coffee. A team of researchers at Kansas State University is hoping to put an end to the hit-and-miss roasting of coffee beans by introducing the coffee industry to the best preparation of three major beans.
Researchers were Natnicha Bhumiratana, graduate student in human nutrition from Bangkok, Thailand; Koushik Adhikari, assistant professor of sensory analysis; and Edgar Chambers IV, director of the Sensory Analysis Center and distinguished professor of sensory analysis and consumer behavior. They examined 10 samples from three different coffee beans in their study, "Green Coffee Beans To Brewed Coffee: Evolution of Aroma Attributes." The study examined the effect of roasting the beans at various degrees, grinding and brewing on the evolution of coffee aroma.
"With the data, we’re hoping to know what roast degree is best for each variety of bean," Bhumiratana said. "This can then be used by the industry to know what the perfect way to roast each bean is so they can bring out the best flavors. They will know what element is responsible for each flavor -- like fruity, nuttiness and sweetness."
For the experiment, 30 different samples of coffee beans were studied. Each bean was either green (raw and unroasted), lightly roasted, medium roasted or darkly roasted, and came from either Ethiopia (Kebado beans), Hawaii (Kona beans) or El Salvador (Bourbon beans).
A trained panel looked at 15 different aroma descriptors (such as sweet, nutty, musty, etc.) and ranked the coffee accordingly.
Bhumiratana said the results were not really that surprising to her.
"I guess if anything surprised me, it was the Kona because it was the sweetest in the darker roast, whereas the other two were sweeter in the lighter roast," she said. Kona is a coffee bean that comes from Hawaii.
Bhumiratana is currently working on her dissertation, which examines the emotional scale one feels from coffee.
"People tend to buy things not only because of the sensory properties associated with it, but also the emotions elicited by the entire consumption experience," Bhumiratana said of her research. "Hence, the development of the scale to measure the emotions evoked by coffee drinking."
Her dissertation will be released in September.
According to Bhumiratana, while coffee aroma has been studied extensively, none of the previous studies have examined the evolution of aromatic attributes of coffee at different states of preparation: raw, roasting, grinding and brewing.
Prepared by K-State media relations and Human Ecology communications