Graduation date: 2008
The effects of the residual salt of surimi on biochemical and physical properties as affected by various freeze and thaw cycles were examined. Fresh Alaska pollock (Theragra chalcogramma) surimi was mixed with 4.0% sugar, and 5.0% sorbitol, along with eight combinations of salt (0.4, 0.6, 0.8, and 1.0 % NaCl) and sodium polyphosphate (0.25 and 0.5%). Surimi was then vacuum packed and stored at -18°C until used. Freeze-thaw (FT) cycles (0, 3, 6, and 9) were used to mimic long term frozen storage. At the time of gel preparation, each treatment was adjusted to maintain 2% salt and 78% moisture. The pH decreased as the residual salt increased during frozen storage. Salt extractable protein (SEP) and Ca²⁺-ATPase activity decreased as FT cycles extended. Regardless of residual salt and phosphate during frozen storage, whiteness value (L*-3b*) decreased as FT cycles extended. Water retention ability (WRA) and texture significantly decreased at higher salt content (0.8 and 1.0 %) after 9 FT cycles.