Phosphorylated fish gelatin (PFG) exhibited preferable physical and chemical properties than fish gelatin (FG) in our previous study. To investigate the application values of PFG, the effects of different ratios (2:1, 1:1 and 1:2) of FG(PFG)/κ carrageenan (κC) on the quality of jelly gels (JGs) were investigated. The sensory quality of PFG:κC (1:2)/FG:κC (1:2) was found to be superior based on sensory evaluations, which was also verified with the results for texture, rheology, etc. Moreover, the structural changes in JGs were related to the introduction of phosphoric acid groups into the molecular chain of gelatin and the protein–polysaccharide interactions. According to the storage results, PFG jelly had better storage quality, higher hardness and chewiness values than those of FG jelly. High-throughput sequencing of JG microbial analysis showed that the addition of PFG changed the amount of microorganisms, microbial species abundance and the microbial composition of JGs, which were also closely related to the storage quality of JGs. In conclusion, the applications of PFG have promising potential to improve the quality of confectionery.

In this study, we developed a novel SERS-active magnetic substrate (MBs@CS@AuNPs) for detecting malachite green (MG) in aquatic products, including shrimp, cod, and aquaculture water. The substrate combines chitosan-functionalized magnetic nanobeads with dense gold nanoparticles. It efficiently enriches MG through electrostatic and π–π interactions, generates high-density plasmonic hotspots for stable signals, and utilizes a superparamagnetic core to concentrate MG molecules. This design achieved an ultralow detection limit of 10⁻⁹ M for MG in aquaculture samples, with a linear range spanning from 10⁻³ to 10⁻¹⁰ M (R² = 0.999). The substrate demonstrated superior performance in untreated, complex food matrices (e.g., shrimp, cod), outperforming conventional magnetic mass spectrometry systems that are prone to matrix interference. This work introduces an innovative approach for detecting harmful residues in food during environmental safety monitoring.

Herein, a dual-modal detection strategy for Salmonella using an engineered bifunctional M13 bacteriophage is presented. A Salmonella-specific binding peptide was fused to the pIII protein, while a streptavidin (SA)-binding nanotag was displayed on the pVIII protein. Taking advantage of the approximately 2700 copies of pVIII per phage, the addition of SA-HRP enabled massive enzymatic loading, which served as the key to generating both SERS and colorimetric signals in the presence of TMB substrate. Under optimized conditions (37 °C, ~1.5 h), the assay achieved limits of detection of 3.4 CFU/mL for the colorimetric mode and 2.7 CFU/mL for the SERS mode. The method exhibited excellent specificity and demonstrated satisfactory accuracy in complex matrices including Penaeus vannamei, beef, and peanuts, highlighting its strong potential for practical application in rapid food safety detection.