CRYOPROTECTIVE EFFECT OF MILK WHEY ON SUR IMI FROM JACK MACKEREL (TRACHURUS-MURPHYI)

Cryoprotective effect of milk whey was studied in surimi from jack mac kerel (Trachurus murphyi) during frozen storage at -18-degrees-C for f ive months. Milk whey was added at level of 4.6, and 8% w/w (with and without 0.2% of ployphosphates). The results were compared with a comm ercial mixture of 8% sucrose-sorbitol (1:1) and a control. Surimi qual ity was evaluated by biochemical, physical and organoleptic tests. The decrease in water holding capacity, protein sulubility, calcium ATPas e activity, and gel formation confirmed that protein denaturation ocur red during frozen storage. These changes were also detected by the pan elist. The decrease of ATPase activity and water holding capacity was reduced by combination of polyphosphates and 8% of milk whey. The best cryoprotective effect was achieved with 8% of milk whey plus 0.2% of polyphosphates and the commercial mixture. The addition of 8% of milk whey improved the sensory characteristic of gel alter 155 days at -18- degrees-C.