contamination by other foods Because parasitic worms are often found in otherwise high-quality fish, the U.S Food Code specifies that fish sold for raw consumption should be frozen throughout for a minimum of 15 hours at –31ºF/–35ºC, or for seven days at –4ºF/–20ºC The exceptions to this rule are the tuna species commonly served in Japanese sushi and sashimi (bluefin, yellowfin, bigeye, albacore), which are rarely infected with parasites Despite this exception, most tuna are blast-frozen at sea so that the boats can stay out for several days at a time Sushi connoisseurs say that the texture of properly frozen tuna is acceptable, but that the flavor suffers Sushi and Sashimi Probably the commonest form of raw fish is sushi, whose popularity spread remarkably in the late 20th century from its home in Japan The original sushi seems to have been the fermented preparation narezushi (p 235); sushi means “salted” and now applies more to the flavored rice, not the fish The familiar bite-sized morsels of raw fish and lightly salted and acidified rice are nigiri sushi, meaning “grasped” or “squeezed,” since the rice portion is usually molded by hand The mass-produced version of sushi found in supermarkets is formed by industrial robots Sushi chefs take great care to avoid contamination of the fish They use a solution of cold water and chlorine bleach to clean surfaces between preparations, and they change cleaning solutions and cloths frequently during service Tart Ceviche and Kinilaw Ceviche is an ancient dish from the northern coast of South America, in which small cubes or thin slices of raw fish are “cooked” by ... Sushi chefs take great care to avoid contamination of the fish They use a solution of cold water and chlorine bleach to clean surfaces between preparations, and they change cleaning solutions and cloths frequently during service... bite-sized morsels of raw fish and lightly salted and acidified rice are nigiri sushi, meaning “grasped” or “squeezed,” since the rice portion is usually molded by hand The mass-produced version of sushi found in.. .The original sushi seems to have been the fermented preparation narezushi (p 235); sushi means “salted” and now applies more to the flavored rice, not the fish The familiar bite-sized morsels of raw fish and lightly