Effect of a collagen peptide-fish oil high internal phase emulsion on the printability and gelation of 3D-printed surimi gel inks.

The effect of a high internal phase emulsion (HIPE) on three-dimensional-printed surimi gel inks was studied. Increasing the concentration of collagen peptide decreased the particle size of HIPE droplets and improved the viscoelasticity and stability. For example, when the collagen peptide concentration was 5 wt%, the viscoelasticity of the HIPE was high, as indicated by the presence of small and uniform particles, which formed a monolayer in the outer layer of the oil droplets to form stable a HIPE. A HIPE was used as the filling material to fill the surimi gel network, which reduced the porosity of the network. Surimi protein and peptides have dual emulsifying effects on the stabilization of oil. After adding the emulsion, the texture, gel properties and rheological properties of the surimi were reduced, and its printing adaptability was improved. This study provides new ideas for the production of surimi and its application in 3D printing.

The effects of polyphenols on fresh quality and the mechanism of partial freezing of tilapia fillets.

BACKGROUND: Fish is one of the most popular foods for consumers because of its abundant nutrition, tenderness and delicious taste. With increasing demand for tilapia fillets, practical preservation is widely used to maintain quality and safety during long-distance transportation and storage. Thus the effects of polyphenols (2 g L-1 ) on color, flavor quality and mechanism of tilapia fillets were studied during 49 days of partial freezing (-4 °C). RESULTS: Treatment with carnosic acid (CA), procyanidin (PA), quercetin (QE) and resveratrol (RSV) inhibited water migration, myoglobin oxidation and psychrophilic bacteria stability during partial freezing storage. Aeromonas and Acinetobacter were the dominant bacteria of tilapia fillets during -4 °C storage. The relative abundance of aromatic substances (T70/2) in the polyphenol groups (>20%) was richer than in the control (CON) group (17%). Partial least squares discriminant analysis results showed that the different odors of the control and polyphenol groups were completely separated. Moreover, 35 fatty acids were identified by gas chromatographic analysis. On 49 days, the ratios of unsaturated fatty acids in the PA group (58.64%), QE group (57.70%) and RSV group (57.25%) were higher than in the control group (57.19%), and the PA group was the highest. CONCLUSION: Polyphenol treatment effectively maintained freshness and improved the quality of tilapia fillets during partial freezing. The polyphenol treatment comprehensively sustained the color and flavor quality of tilapia fillets found in the proposed mechanism. In particular, PA treatment was considered a potential method for preserving the freshness of fillets. © 2022 Society of Chemical Industry.