As the Kona Coffee Cultural Festival celebrates its 39th year this week, a controversy that started two decades ago about what defines Kona coffee is brewing anew.

Tom Greenwell, president of Greenwell Farms in Kealakekua, remembers the debate back then over a bill that would have required coffee processors to use at least 51 percent of Kona coffee in their blends “;if they wanted to use our good name.”;

“;Kona coffee had a name even back in 1870 in my great-great-grandfather's day,”; he said, crediting the area's ideal weather and climate for growing the flavorful beans.

Kona coffee is costly, so blenders convinced legislators that a minimum of only 10 percent Kona coffee should be required. They were afraid there would be no market for the pricier product that would result if 51 percent were the law, Greenwell said.

The 10 percent law passed in 1991, and Greenwell said he believes farmers and the entire industry benefited.

That was then.

For the past four years, the Kona Coffee Farmers Association, which represents more than 200 of the estimated 600 to 700 farmers in Kona, has been pushing legislators to require a minimum of 50 percent, said association President Bruce Cor-ker. Blends with only 10 percent Kona coffee are not worthy of the name, the group asserts.

“;You don't see a 10 percent French champagne, 10 percent Napa Valley wine or 10 percent Idaho potatoes,”; says Corker. “;We are the only region in the world treating one of its specialty agricultural crops this way, which encourages the use of deceptively labeled Kona coffee.”;

The law allows labels to be printed with the word “;Kona”; in large letters all over the bag, but the “;10 percent Kona blend”; is only mentioned once in small print, he said. Tourists especially become confused and end up “;paying a premium price for cheap foreign coffee,”; Corker said.

The controversy has divided the Kona coffee community, agrees Greenwell.

“;Eighteen years ago we were struggling trying to sell coffee,”; he said. “;Today the market's been great. For the last 10 years, prices have been climbing, and farmers have actually been able to make money.”;

State Rep. Denny Coffman of Kona introduced a bill addressing the percentage issue, but it died this year.

Now the focus is on a proposed study of the economic impact of increasing the required percentage. Coffman is trying to find more than $100,000 to fund the study, supported by the Kona Coffee Council, the Hawaii Coffee Association and the Coffee Growers Association.

Their members fear there will not be enough demand for raw coffee cherries if the percentage increases and the price of blended coffee doubles, Coffman said.

“;We would be in favor of (changing the law) if a study was done that proves it would have no adverse effect on cherry farmers who sell the raw product,”; said Greenwell, also president of the Kona Coffee Council and treasurer of the Hawaii Coffee Association. “;That is who we need to protect.”;

Corker said his association believes the large Honolulu-based coffee blenders favor the “;study and stall”; tactic because they make exorbitant profits.

Jim Wayman, president of Hawaii Coffee Co., the largest coffee processor in the state, says his Royal Kona brand offers a 10 percent blend in an 8-ounce bag for about $5.

“;Consumers vote with their wallet,”; said Wayman, a four-time president of the Hawaii Coffee Association. “;We've offered the 10 percent product for 40 years. ... They must not think it's junk. It's their favorite coffee.”;

Especially beneficial to the industry has been the exposure of the product through wholesale markets in McDonalds' Restaurants, 7-Eleven and major Hawaii hotels, Wayman said.