Medium-grade Alaska pollock surimi was used to investigate the effects of functional protein additives on texture and colors. Torsion failure and differential scanning calorimetry tests were applied to measure gel strength, gel deformability, and calorimetric properties. CIE Lab color values were also measured. Shear stress values of gels and peak temperature of DSC thermograms were all increased. Shear strain, a good indicator of protein-protein interaction, was increased only by addition of egg white and beef plasma protein. Yellowness @*) values were affected by all additives except frozen egg white. Whiteness index (L*-3b*) was a more effective indicator to differentiate additives.

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Relatively higher protein recovery was obtained in acid-aided processing. Solubility was lowest at pH 5 and gradually increased up to pH 11.0. A sharp increase in solubility occurred at alkaline pH between 9.5 and 11.0 and at acidic pH between 3.0 and 1.5. Cathepsin B and L showed higher activities in acid surimi than conventional surimi. Acid-aided surimi did not show Ca-and Mg-ATPase activity and also had lower surface hydrophobicity and sulfurhydryl contents than conventional surimi. Acid processing resulted in low breaking force, possibly due to the activity of retained cathepsin L enzymes. Myosin heavy chain (MHC) and actin were degraded in acid processing and produced major bands right below MHC and actin.

Colors (CIE L*, a*, and b*) of Alaska pollock (7'heragra chalcogramma) and Pacific whiting (Me&c&s productus) surimi gels were evaluated and related to compositional and physical conditions during preparation and measurements. Ten samples were used in each treatment. Water addition, sample size, species, cooking and test temperatures, and freeze/thaw affected lightness (L*) and yellowness (b*) values, while outside light conditions at measurement did not affect colors. Greenness (-a*) values were less affected by all conditions.

The protein solubility and molecular‐weight distribution of freeze‐dried sarcoplasmic proteins (SPs) from rockfish treated under low and high pH as well as various NaCl concentrations were elucidated. The solubility of SPs was significantly suppressed at an acidic pH (2.0–4.0) and in the presence of high salt concentration (0.5 M NaCl). The least amount of protein was lost when SPs were treated at pH 2.0 or 3.0 followed by precipitation at pH 5.5. The interaction of SPs with Alaska pollock surimi (myofibrillar proteins) was also investigated. The addition of SPs appeared to delay the thermal denaturation of myosin and actin. The SPs positively contributed to the gelation of myofibrillar proteins as judged by breaking force.

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Capacitive (Radio Frequency) dielectric heating has great potential for achieving rapid and uniform heating patterns in foods, providing safe, high quality food products. This review describes and discusses the major technology behind capacitive (RF) dielectric heating in food processing and preservation, the current applications of the technology in the industry, the potential use of mathematical modeling for heating system design, and the major challenges facing the use of this technology in food processing. A vast amount of work is still necessary to further understand the dielectric properties of both food and packaging materials in order to refine system design and maximize performance of this technology in the field of packaged food products. Various economic studies will also play an important role in understanding the overall cost and viability of commercial application of this technology in food processing.