Reuters March 19 , 2011 At least three U.S. roasters announced this week that they were raising coffee prices after arabica coffee futures fell from a 34-year high. Kraft Foods Inc (KFT.N), one of the top coffee roasters in the United States, raised prices for many of its roast coffees by 22 percent, marking its fourth and biggest price hike in a year, effective on March 16. On the same day, Massimo Zanetti Beverage USA raised the cost of its well-known brands including Chock Full o'Nuts, by an average of 12 percent. On March 18, Starbucks Co (SBUX.O) said it would raise the price of its packaged coffee by an average of 12 percent. Even robusta coffee, typically processed into instant coffee or used as a cheaper alternative in roasted blends, has joined the rally and on Friday hit a three-year high at $2,672 per tonne, basis May LRCc2. Roasters have widely been forced to raise their prices sporadically since June 2010 when the rally began, initially spurred by fund bu...