EFFECT OF DEFATTING PROCESSES ON THE TEXTURIZATION OF FISH-PROTEIN USING A TWIN-SCREW EXTRUDER

Minced meat from herring was defatted , then extruded by a twin-screw extruder together with soybean protein isolate .This operation was carried out at a feed rate of 33kg h , a screw speed of 120r min and a barrel temperature of 160 ℃.The results indicated that the defatted fish meat with fat contents of 2.8 % and 1.6 %(dry base)respectively showed better texturization properties .The extrudates appear a sponge structure , and have the chewiness properties of meat .The results of scanning electron micrograph show that the fine structure of extrudates consists of a well-aligned fibrous structure , and the fibers parallel to the entrusion direction .