Improving the Gel Quality of Threadfin Bream (Nemipterus spp.) Surimi Using Salted Duck Egg White Powder.

The effect of salted duck egg white powder (SDEWP) as a source of salt at different salt equivalent (SE) levels (0−2.5% SE) on gel qualities and texture properties of threadfin bream surimi was investigated. SDEWP possessed a high protein (64.59%) and salt (34.86%) concentration. The breaking force of surimi gel increased by the amount of SDEWP (p < 0.05). The addition of SDEWP up to 1.5% SE into the surimi gel has significantly increased the deformation (13.8%) and decreased the expressible moisture content (38.5%). Hardness, gumminess, and chewiness were augmented as higher levels of SDEWP were added, whereas cohesiveness decreased when the SDEWP above 1.5% SE was used. The incorporation of SDEWP had no significant effect on the springiness (p < 0.05). Less proteolytic degradation was observed in the surimi gel fortified with SDEWP. A higher amount of added SDEWP enhanced the whiteness of the surimi gel (p < 0.05). A denser and more ordered gel network was attained when SDEWP with 1.5% SE was added. SDEWP could be exploited as a source for salt and non-fish proteins in threadfin bream surimi, in which SDEWP containing 1.5% SE could significantly improve the quality of surimi gel.

Effects of κ-carrageenan on gel quality of threadfin bream (Nemipterus spp.) surimi containing salted duck egg white powder.

This study aimed to evaluate the combined effect of κ-carrageenan and salted duck egg white powder (SDEWP) in improving the gel quality of threadfin bream surimi. Effects of κ-carrageenan at different levels (0-2 %) on gel properties of threadfin bream surimi without and with salted duck egg white powder at 3 % (protein equivalent) were investigated. A combination of 0.5 % κ-carrageenan and SDEWP increased breaking force of surimi gel by 139.7 % and deformation by 55.1 %, compared to the control (P < 0.05). The expressible moisture content (EMC) was decreased by 50.0 % in the surimi gel added with 0.5 % κ-carrageenan and SDEWP. Hardness, cohesiveness, gumminess, and chewiness of surimi gel were also improved (P < 0.05). However, springiness of surimi gel was not affected. SDEWP reduced proteolytic degradation in surimi gel. Surimi gel with augmented whiteness was attained when κ-carrageenan was added at higher levels. Microstructure of surimi gel shown that the gel became denser and more uniform when added with 0.5 % κ-carrageenan and SDEWP. Therefore, κ-carrageenan can be used to enhance the effectiveness of SDEWP and further improve the gel quality of threadfin bream surimi added with SDEWP.

Asian Carp, an Alternative Material for Surimi Production: Progress and Future.

Asian carp is a general designation for grass carp, silver carp, bighead carp, and black carp. These fish species belong to the family Cyprinidae. In 2018, more than 18.5 million tons of Asian carp were produced globally. Asian carp can be used for producing surimi, a stabilized myofibrillar protein concentrate that can be made into a wide variety of products such as imitation crab sticks, fish balls, fish cakes, fish tofu, and fish sausage. Surimi is usually made from marine fish, but Asian carp have been widely used for surimi production in China. The quality of surimi is affected by various factors, including the processing methods and food additives, such as polysaccharides, protein, salt, and cryoprotectant. With an impending shortage of marine fish due to overfishing and depletion of fish stocks, Asian carp have a potential to serve as an alternative raw material for surimi products thanks to their high abundancy, less emissions of greenhouse gases from farming, desirable flesh color, and sufficient gel forming ability. The utilization of Asian carp in surimi production could also contribute to relieving the overflow of Asian carp in the United States.