Effects of Salinity on Physicochemical Properties of Alaska Pollock Surimi after Repeated Freeze–Thaw Cycles

Abstract

The effects of residual salt in surimi on physicochemical properties as affected by various freeze and thaw (FT) cycles were examined. Fresh Alaska pollock surimi was mixed with 4.0% sugar and 5.0% sorbitol, along with 8 combinations of salt (0.4%, 0.6%, 0.8%, and 1.0% NaCl) and sodium polyphosphate (0.25% and 0.5%), vacuum-packed, and stored at -18 degrees C until used. FT cycles (0, 6, and 9) were used to mimic long-term frozen storage. At the time of gel preparation, each treatment was appropriately adjusted to maintain 2% salt and 78% moisture. The pH decreased as residual salt increased during frozen storage. Salt extractable protein (SEP) decreased (P < 0.05) as FT cycles extended from 0 to 9. Regardless of residual salt and phosphate concentration during frozen storage, whiteness value (L*- 3b*) decreased (P < 0.05) as FT cycles extended, except for samples with 0.4% salt/0.5% phosphate and 0.6% salt/0.25% phosphate. Water retention ability (WRA) and texture significantly (P < 0.05) decreased at higher salt content (0.8% and 1.0%) after 9 FT cycles, indicating higher residual salt concentration can shorten the shelf life of frozen surimi. Our study revealed lower residual salt concentration and higher phosphate concentration are likely to extend the shelf life of frozen surimi.

Comparative Study of Sodium Bicarbonate on Gelling Properties of Alaska Pollock Surimi Prepared at Different Freezing Rates

“…Comparing sample mean values at each test period (Table 1), SSP values tended to decrease during 12 months of frozen storage. A similar trend was observed in other studies as well (Sultanbawa and Li-Chan 1998;Reynolds et al 2002;Zhou et al 2006;Kang et al 2008;Mahawanich et al 2010). Reynolds et al (2002) showed that SSP values of Pacific whiting surimi decreased during 9 months of frozen storage regardless of freezing method, either slow, fast or freeze-dried.…”

“…Park et al (1993) also found a decrease of approximately 0.7 pH units between prerigor and meat after 1 month of frozen storage. Others have demonstrated a decrease in the pH of frozen surimi (MacDonald et al 1992;Kang et al 2008;Huda et al 2011;Nopianti et al 2011). This decrease is believed to be caused by an increased amount of organic acids, namely lactic acid derived from glycogen and glycolysis (Suvanich et al 2000;Huda et al 2011).…”

Gelation characteristics of tropical surimi under water bath and ohmic heating

“…WHC of all gels was evaluated according to Kang, Hunt, and Park (2008). Cooked gel cut into small pieces and 0.4 AE 0.05 g was placed in a micro-centrifuge tube (Eppendrof, Hamburg, Germany) with a nylon screen and 0.45-mm pore size.…”

Salt substitution in surimi seafood and its effects on instrumental quality attributes

“…3). Kang, Hunt, and Park (2008) also showed that addition of salt to Alaska pollock surimi decreases (P < 0.05) whiteness. Surimi gels with salt substitute had generally comparable L* to the gels with respective salt concentration (Table 3).…”