Coffee: brewing's link to cholesterol.

Last year, Dutch researchers identified two compounds in coffee oils that can raise cholesterol in the blood. The good news, the group reported earlier this year, is that paper filters virtually eliminate those diterpenes from drip-brewed coffee (SN: 2/4/95, p.72).

Now, the same team offers generally reassuring news for many millions of people who perk up each morning with coffee brewed in some other fashion.

Rob Urgert and his colleagues at the Agricultural University in Wageningen, the Netherlands, collected samples of brewed coffee from restaurants and households in Europe and North Africa. They also reconstituted 13 regular and 6 decaffeinated brands of instant coffee from five nations for analysis, and they brewed another 20 regular and 5 decaf brands from 10 countries. The latter included two U.S. brands each by Hills Brothers, Folgers, and Maxwell House.

The instants contained only "minimal" diterpenes, Urgert's team reports in the newly released August Journal of Agricultural and Food Chemistry. Espresso, in contrast, contained the most--some 6 to 12 milligrams of the diterpene cafestol alone per 150 milliliters of coffee. However, because a typical serving of espresso is so small, a portion yielded only about one-quarter of the amount in a cup of such boiled brews as Scandinavian or Turkish and Greek coffees--types known to elevate cholesterol.

Urgert expressed surprise "that percolated coffee, though it's not paper-filtered, contained negligible amounts of [the diterpenes] cafestol and kahweol." He now suspects that the basket of grounds through which this brew repeatedly percolates serves as a filter for those compounds. Such filtering does not occur in a French press coffeemaker, whose plunger pushes grounds to the bottom of the pot after 5 or more minutes of brewing. This coffee met or exceeded the diterpene content of Scandinavian and Turkish or Greek brews.

The Dutch team concludes that drinking five cups of the increasingly popular French press coffee daily could raise cholesterol by 8 to 10 milligrams per deciliter of blood. It would take 15 or more servings of espresso or mocha to do the same.