Inoculation of starter culture is a viable method to improve the quality of fermented foods, but its effect on the flavor metabolite profiles and the underlying mechanisms are still unclear. This study aimed to elucidate the effects of starters (Lactiplantibacillus plantarum (LP) and Staphylococcus simulans (SS) individually or in combination (LS)) on the flavor metabolite profiles of fermented sausages via metabolomics and genomics. L. plantarum markedly modified the composition of bacterial communities and made Lactobacillus spp. dominant in sausages (98.29% and 85.03% in LP and LS groups, respectively). Additionally, inoculation with a single starter, L. plantarum, and a mixed starter yielded similar non-volatile flavor metabolites, which were mainly characterized at the amino acid and peptide levels (relative intensities of 349.65 and 348.62 for the LP and LS groups, respectively). Meanwhile, the mixed starter group had the most volatile flavor metabolites (relative intensity of 34728.67), some of which were contributed by L. plantarum, such as ethyl acetate (relative intensities of 583.33 and 588.33 for the LP and LS groups, respectively) and benzaldehyde (relative intensities of 786.67 and 909.00 for the LP and LS groups, respectively), and several of which were generated by S. simulans, such as ethyl propionate (relative intensities of 214.67 and 136.67 for the SS and LS groups, respectively) and benzyl alcohol (relative intensities of 720.00 and 656.00 for the SS and LS groups, respectively). Furthermore, L. plantarum was found to possess more genes encoding peptidases (48) and carbohydrate-active enzymes (124), while S. simulans had more genes related to lipid hydrolysis (12). In conclusion, differences in the properties and combinations of indigenous strains play a crucial role in the generation of flavor metabolites in sausages.

Interfacial modification of proteins refers to modifying interfacial proteins during the post-emulsification stage to enhance the thickness and rigidness of interfacial protein films and consequently improve the physicochemical properties of emulsions. Moreover, interfacial modification of proteins can avoid some of the adverse effects of pre-modified proteins before emulsification on emulsion properties. However, in-depth research and a systematic summary of the existing research on interfacial modification of proteins are still lacking up to now. Therefore, this article reviews several widely used methods to modify interfacial proteins, such as enzymatic cross-linking, polysaccharide modification, polyphenol modification and oxidative modification, with special reference to their principles and effects on improving emulsion properties. Besides, future development directions are discussed, with the aim to provide a theoretical basis and technical support for further improving the physicochemical properties of emulsions.

In this study, the effects of gelatin (0%, 2%, 4%, 6% and 8% (relative to meat mass)) on the 3D printing forming stability of chicken meat paste were investigated by rheological tests, gel strength measurement, nuclear magnetic resonance, and scanning electron microscopy. The results showed that chicken meat paste had shear thinning behavior irrespective of whether or not gelatin was added, which was suitable for 3D printing. Gelatin addition enhanced the viscosity and gel strength of chicken meat gel systems, thus effectively improving the 3D printing forming stability of chicken meat paste. However, excessive addition of gelatin affected the extrusion process of chicken meat paste and reduced the shape accuracy of printed samples. Addition of 4% gelatin resulted in good accuracy and forming stability, and the collapse rate of the printed shape was 2.46%. The cooking quality of the 3D printed sample with 4% gelatin was evaluated. It was found that 3D printing could increase its cooking loss, but improve its texture properties.

Surface-enhanced Raman spectroscopy (SERS) biosensors have attracted considerable attention for sensitive bacterial detection. In this study, we established a SERS biosensor for highly sensitive detection of Salmonella typhimurium (S. typhimurium) via the use of porous organic framework-immobilized gold nanoparticles (COF@AuNPs) composites as nanocarriers combined with gold and silver core-shell nanoflowers-enhanced (Au@AgNFs) substrates to increase the number and intensity of Raman hotspots synergistically. The proposed COF@AuNPs effectively immobilized the Au NPs in the homogeneous pores of the COF, which prevented the aggregation of the Au NPs and provided many binding sites and a stable microenvironment for aptamer loading. This SERS sensor has a linear range of 10² - 10⁸ CFU/mL and a detection limit of 8.6 CFU/mL. The SERS aptasensor rapidly and accurately detected bacteria in real chicken samples, allowing early diagnosis of S. typhimurium. This SERS aptasensor provides new strategies for sensitive bacterial detection and may reveal new methods for monitoring other biomolecules.

The luteolin (Lut) binding with myofibrillar protein (MP) can enhance the functionality of proteins, having the potential to ameliorate obesity in the form of dietary intervention. Our previous research unveiled the in vitro cell viability and antioxidant properties of the MP-derived and Lut-containing multicomponent peptides (MDLPs). This study aimed to further investigate the effect of MDLPs intervention and downstream effects on lipid metabolism using integrated physiological and multi-omics approaches. The results demonstrated that MDLPs significantly ameliorated steatosis and systemic oxidative stress in HepG2 cells induced by a high-fat (HF) reagent. Combining metabolomic and transcriptomic analysis indicated that PPAR, FoxO, and amino acids metabolism signaling pathways played pivotal roles in response to the MDLPs intervention, primarily through upregulating PPARα, PPARγ, FOXO1, and PLIN4. The abundance of potential disease biomarkers (4-hydroxynonenal and hydroxylinoleic acid) were enhanced. The outcomes of this research provide the theoretical basis for the formulation of novel meat products with anti-obesity activity.

Lactic acid bacteria and coagulase-negative staphylococci play an important role in the production of fermented sausages, such as inhibiting the growth of undesirable bacteria and antioxidant. In this study, the effects of inoculation with different starter cultures (Lactiplantibacillus plantarum HN108 and Staphylococcus simulans NJ209) on the free amino acids (FAAs), biogenic amines (BAs) and volatile compounds of fermented sausages were investigated using an amino acid analyzer, ultra performance liquid chromatography and gas chromatography-ion mobility spectrometry, respectively. The pH and carbonyl content of the inoculated group was significantly lower than those in the control group (P < 0.05). L. plantarum HN108 significantly reduced the content of FAAs and BAs in fermented sausage production (P < 0.05), while S. simulans NJ209 promoted the formation of FAAs (especially bitter amino acids) and exhibited slight BAs-reducing activity. In addition, L. plantarum HN108 promoted the formation of volatile compounds such as ketones, alcohols and alkenes in sausages. In conclusion, L. plantarum HN108 could contribute to reducing the content of putrescine and tyramine and forming the desirable flavor compounds in fermented sausages. Thus, L. plantarum HN108 is expected to be a starter culture that can improve the safety and flavor of fermented sausages.

The sensory perception of food is a dynamic process, which is closely related to the release of flavor substances during oral processing. It’s not only affected by the food material, but also subjected to the individual oral environment. To explore the oral processing characteristics of soft-boiled chicken, the sensory properties, texture, particle size, viscosity, characteristic values of electronic nose and tongue of different chicken samples were investigated. The correlation analysis showed that the physical characteristics especially the cohesiveness, springiness, resilience of the sample determined oral processing behavior. The addition of chicken skin played a role in lubrication during oral processing. The particle size of the bolus was heightened at the early stage, and the fluidity was enhanced in the end, which reduced the chewing time to the swallowing point and raised the aromatic compounds signal of electronic nose. But the effect of chicken skin on chicken thigh with relatively high fat content, was opposite in electronic nose, which had a certain masking effect on the perception of umami and sweet taste. In conclusion, fat played a critical role in chicken oral processing and chicken thigh had obvious advantages in comprehensive evaluation of soft-boiled chicken, which was more popular among people.

Chilled chicken has become the mainstream of chicken consumption. In order to explore the effect of post-mortem aging on water-soluble flavor precursors of chicken, pH, adenosine triphosphate (ATP) degradation, flavor nucleosides, free amino acids and water-soluble low molecular weight peptides were determined using Qingyuan partridge yellow-feathered broilers as material during 0–4 °C post-mortem aging in 48 h. The results showed that the pH value fell to the limit pH 5.64 (4 h) in chicken breast and 6.21 (3 h) in thigh. Regardless of chicken breast or thigh, ATP dropped rapidly within 3 h. It was found that the K-value in chicken thigh was the lowest at 2 h indicating the freshness was the best. Considering the equivalent umami concentration (EUC), the value at 3 h and 4 h was relatively high, but the corresponding electronic tongue umami value was not high, which further showed that the water-soluble low molecular taste peptide played an important role on the post-mortem aging process. Combined with cluster analysis and partial least squares discriminant analysis (PLS-DA), it was preliminarily inferred that the optimal time for chilled chicken during 0–4 °C post-mortem aging was 2 h, which could provide a theoretical basis for the further processing of fresh chicken.