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Bacterial cellulose (BC) was used as a reinforcing agent, citric acid (CA) as a cross-linking agent, and CMC@AgNPs as antibacterial nanomaterials, in which CMC@AgNPs were reduced from AgNO

Cell cultured meat (CCM) production is an innovative technology that does not depend on livestock farming practices to produce meat. The construction of structured CCM requires a three-dimensional (3D) scaffold to mimic the extracellular matrix to provide mechanical support for the cells. Furthermore, the 3D scaffolds should be edible and have good biocompatibility and tissue-like texture. Here, we demonstrated a 3D edible chitosan‑sodium alginate-collagen/gelatin (CS-SA-Col/Gel) scaffold that can support the adhesion and proliferation of porcine skeletal muscle satellite cells, culminating in the construction of a structured CCM model. The 3D edible scaffolds were prepared by freeze-drying using electrostatic interactions between chitosan and sodium alginate. Initially, the physicochemical properties and structural characteristics of different scaffolds were explored, and the biocompatibility of the scaffolds was evaluated using the C2C12 cell model. The results showed that the 2-CS-SA-Col

In this study, the CS-DAS aerogels were prepared using chitosan (CS) crosslinked by dialdehyde starch (DAS), with the best absorption and mechanical properties at the weight ratio of CS to DAS being 7:3. The copper nanoparticles (CuNPs) were first prepared by green reduction method, then encapsulated by liposomes (Lip-CuNPs) for controlling their sudden release. The antibacterial aerogels (CD/Lip-CuNPs) were developed by incorporating the Lip-CuNPs into the aerogel (7:3). The porous network structure of aerogels realized the further gradual release of CuNPs. The CD/Lip-CuNPs aerogels had good antimicrobial properties, which could preserve fresh pork for 14 d at 4 °C without spoilage. Moreover, the CuNPs migrated from the aerogels into fresh pork was at a safe level of 3.38 mg/kg after 14 d at 4 °C. The obtained antibacterial CD/Lip-CuNPs aerogels had the potential for extending the shelf life of fresh meat.

Nano-bacterial cellulose (BC), as a reinforcing agent, was used to prepare the agar-based edible films. Effects of BC content (0, 3, 5, 8 and 10%, wt% based on the agar) on the rheological properties of film-forming solution (FFS), and on structure, morphology, crystallinity, and thermal properties of films were investigated. Results of rheological and FTIR analyses revealed that interactions between BC and agar were formed through hydrogen bonds. The crystallinity and the thermal stability of films were improved by addition of BC analyzed by XRD and TGA, respectively. Compared with high BC concentrations (8–10%), a good dispersion of BC at low concentrations (3–5%) in the films was observed by SEM. Moreover, BC addition (10%) significantly decreased moisture content (MC), water solubility (WS) and water vapor permeability (WVP) by 60.4%, 13.3% and 25.7%, respectively. The tensile strength (TS) of films increased from 22.10 to 44.51 MPa after addition of BC (0–10%), whereas the elongation at break (EAB) initially increased with increasing BC concentrations (0–5%), and then decreased with further addition of BC (8–10%). Consequently, agar-based edible films reinforced by moderate nano-BC have the potential as a packaging film for food products.

The objective of this study was to investigate the ability of thermally degraded gelatin to bind aroma compounds such as nonanal, 2-heptanone, 1-octen-3-ol, hexyl acetate and 2-pentyl furan. Binding ability was strongly affected by changes in thermal-degradation products, the structure and surface hydrophobicity of proteins during heating (1–4 h), through analyzing the results of GC-MS, SDS-PAGE, LC-MS/MS, free amino acid, circular dichroism spectra, Fourier transform infrared (FT-IR) spectroscopy, zeta potential, and surface hydrophobicity. Binding ability of gelatin to aroma compounds increased from 12-14% to 29–35% after heating for 4 h. During the first 1 h of heating, there was no significant increase in surface hydrophobicity due to the effects of degradation and unfolding of protein and protein aggregation, thus the increase in zeta potential and free proline caused by gelatin degradation was likely responsible for the increase in binding ability through electrostatic interactions and hydrogen bonding, respectively. After heating for 2–3 h, unfolding and degradation of gelatin played a leading role in exposure of more hydrophobic amino acids on the protein surface, suggesting an enhancement of binding ability due to hydrophobic interaction. Moreover, effects of zeta potential, exposure of more proline on the interface, and increase in free proline caused by protein degradation could also enhance the affinity of gelatin to flavor compounds. After heating for 4 h, exposure of more hydrophobic amino acids and free proline continued to increase flavor-binding ability, although zeta potential decreased. The results provided insight into improving flavor profile of meat matrix.

High levels of polyphenols can interact with myofibrillar proteins (MPs), causing damage to a MP emulsion gel. In this study, β-cyclodextrins were used to reduce covalent and non-covalent interaction between epigallocatechin-3-gallate (EGCG) and MPs under oxidative stress. The loss of both thiol and free amine groups and the unfolding of MPs caused by EGCG (80 μM/g protein) were significantly prevented by β-cyclodextrins, and the structural stability and solubility were improved. MP emulsion gel treated with EGCG (80 μM/g protein) had the highest cooking loss (68.64%) and gel strength (0.51 N). Addition of β-cyclodextrins significantly reduced cooking loss (26.24-58.20%) and improved gel strength (0.31-0.41 N) of MP emulsion gel jeopardized by EGCG under oxidative stress. Damage to the emulsifying properties of MPs caused by EGCG was significantly prevented by addition of β-cyclodextrins. β-cyclodextrins reduced interaction between EGCG and MPs in the order Methyl-β-cyclodextrin > (2-Hydroxypropyl)-β-cyclodextrin > β-cyclodextrin. In absence of EGCG, addition of β-cyclodextrins partly protected MPs from oxidative attack and improved its solubility. It is concluded that β-cyclodextrins does not markedly reduce the antioxidant ability of EGCG according to carbonyl analysis, and can effectively increase EGCG loading to potentially provide more durable antioxidant effect for meat products during processing, transportation and storage.

The effects of rosmarinic acid (RA) (12, 60 and 300 μM/g protein) on the textural properties and stability of oxidized myofibrillar protein (MP) emulsion gels were investigated. A low dose (12 µM/g) of RA significantly prevented the loss of thiol and e-NH2 groups and the unfolding of the oxidized MP. However, a high dose of RA (300 µM/g) covalently and non-covalently interacted with the MPs, which induced a significant loss of thiol and e-NH2 groups and aggregation of the MPs, causing decreased solubility, resulting in a poor three-dimensional emulsion gel network, and hence, higher cooking loss and lower gel strength. Moreover, the emulsifying properties of the MP emulsion gel were jeopardized by 300 µM/g RA. A high concentration of NaCl (0.6 M) enhanced the interaction between RA and MPs, increasing deterioration of the internal structure and leading to extremely unstable emulsifying properties of the MP emulsion gel.

Films with antioxidant activity were prepared by combining chitosan (CH) and epigallocatechin-3-gallate (EGCG) with nano-bacterial cellulose (BC) as a reinforcement agent. Results showed that BC addition improved the qualities of films jeopardized by EGCG. Fourier Transform Infrared (FTIR) spectroscopy analysis confirmed that there were intermolecular interactions among BC, CH and EGCG though hydrogen bonding. Consequently, BC addition increased the crystallinity and thermal stability of CH-BC5/10-EGCG15/30 films analyzed by X-ray diffraction (XRD) and thermogravimetric (TGA) analysis. BC addition also significantly decreased water solubility (WS), from 26.54% to 20.80%, increased tensile strength (TS), from 18.71 to 44.17MPa, and increased elongation at break (EAB), from 2.72% to 7.34%. Moreover, BC and EGCG had high affinity for each other, as BC addition lowered the release of EGCG from CH films with a higher ABTS radical scavenging ability. Therefore, BC can be used as a sustained release carrier of EGCG in antioxidant active films.

The objective of this study was to explore the oxidative modification induced by AAPH (2,2'-azobis (2-amidinopropane) dihydrochloride) on the microbial transglutaminase (MTGase) cross-linking reaction and gelling properties of silver carp myofibril protein (SCMP). Compared to AAPH treatment, MTGase addition resulted further changes of protein properties as evidenced by the decreasing free amino and thiol group content, the decreased secondary and tertiary structure, and the increasing storage modulus (G') and gel strength (P 0.05). The proper oxidation induced by AAPH (5 mM) promoted the glutamine-lysine and disulfide cross-linking due to MTGase (10 U/g). Therefore, the quality of the SCMP gel was improved with a good water-holding capacity (WHC), gel strength and G'. This results could lay a theoretical foundation for the development of silver carp surimi products with good quality. Chemical compounds: (2,2'-azobis(2-amidinopropane)dihydrochloride (PubChem CID:76344); O-Phthalaldehyde (PubChem CID:4807); 5,5'-Dithiobis(2-Nitrobenzoic Acid) (PubChem CID:6254); 8-Anilino-1-naphthalenesulfonic acid (PubChem CID:1369); Acrylamide (PubChem CID: 6579); β-Mercaptoethanol (PubChem CID: 1567); Sodium dodecyl sulfate (PubChem CID:3423265).

The effects of nonenzymatic glycation on the binding capacity of beef myofibrillar proteins (MP) to aldehyde flavour compounds were investigated. The binding capacity was significantly increased due to the partial unfolding and flexible secondary structure of the glycated MP. Unfolding played a dominant role in binding due to the prevention of protein aggregation by steric hindrance originating from glycation with glucose (Glu), while glycation with glucosamine (GluA) induced substantial aggregation due to cross-linking. Therefore, the MP glycated with Glu had a higher binding capacity for aldehyde flavour compounds compared to MP glycated with GluA. In a competitive binding system, the MP glycated with Glu had a higher binding capacity for long-chain aldehyde flavour compounds. However, the MP glycated with GluA had a higher binding capacity for short-chain aldehyde flavour compounds, which were more likely to interact with the binding sites shielded in the protein aggregate. Nonenzymatic glycation represents a potential method to enhance the flavour intensity of meat products with high-protein levels.

Bacteriocins are heat-stable, antimicrobial peptides produced by many organisms, including lactic acid bacteria (LAB). In this study, Lactobacillus casei (L. casei) was isolated from a traditional Chinese fermented vegetable ( Jiangshui Cai ). Among the isolates, L. casei was found to be inhibit the growth both Gram-positive and Gram-negative indicator strains. A tomato-based medium was optimized for the growth of L. casei , taking care to exclude constituents that might compromise bacteriocin purification. Purified bacteriocin from L. casei (Purified through Sephadex G-25, HiPrepQXL 16/10 column of AKTA, RPC column of AKTA and reverse phase HPLC) LiN333 showed antimicrobial activity after treatment at a wide range of temperatures (60, 80, 100, 121 °C) and pH levels (pH 3, 4, 5, 6, 7, 8, 9). LiN333 displayed antimicrobial ability against Gram positive and Gram negative pathogenic and antibiotic resistant bacteria, including Listeria . MALDI-TOF-MS determined that the molecular weight of LiN333 was 4890 Da. Scanning electron microscopy (SEM) was used to observed the mechanism of action of LiN333. The minimum inhibitory concentration against E. coli and S. aureus was 15 μg/ml. LiN333 shows potential application as a food preservative based on its mechanism of action and its stability across a range of pH values and temperatures.

Antioxidant properties and flavor characteristic profile of pomegranate wine during winemaking were investigated. The total phenol content and radical scavenging activity exhibited a slightly decrease in the end edge. Punicalagins and gallic acid were revealed to be the most abundant phenolic compounds, followed by ellagic acid and vanillic acid. These constituents were mainly responsible for the effective antioxidant capacity of pomegranate wine. The major changes of flavor qualities occurred in the initial stage, particularly 0-4day of fermentation. Fermentation significantly reduced the relative content of aldehydes, ketones, heterocyclic and aromatic compounds, but promoted the generation of esters and alcohols. This is the first time of using E-nose and E-tongue to monitor odour and taste changes in the brewing process of pomegranate wine. The study may provide a promising instruction for improving functional features and quality control of the pomegranate wine.

Biocomposite films were manufactured by combining protein extracted from buckwheat distiller’s dried grains with bacterial cellulose (BC). The film microstructures showed that BC is compatible with protein matrix and endows the film with high rigidity. Differential scanning calorimetry (DSC) showed that BC can promote thermal stability of the composite films. BC promoted the transition from a Newtonian to a non-Newtonian fluid and the shear thinning behavior of protein-BC solution. Fourier Transform Infrared (FTIR) spectroscopy showed the main functional groups’ absorption peaks shifted to lower wavenumbers. Results of both FTIR and viscosity analysis proved the formation of intermolecular interactions through hydrogen bonds. These bonds affected film characteristics such as moisture content (MC), water solubility (WS), and water vapor permeability (WVP), which decreased with addition of BC. The WVP (6.68 ± 0.78 − 5.95 ± 0.54 × 10−10 g m/Pa s m2) of the films were lower than other protein films. Tensile strength (TS) values of films containing 1.8% and 2.0% BC (14.98 ± 0.97 and 15.03 ± 2.04 MPa) were significantly higher than that of pure protein films (4.26 ± 0.66 MPa). Combination of proteins extracted from a waste product and BC led to composite films with low water vapor permeability and excellent mechanical properties.

In this study, 1500 W, 40 kHz ultrasound was used to treat chicken muscle during 5 days of ageing after slaughter. Ultrasound treatment-induced typical apoptosis was applied to chicken muscle after slaughter. Our Western blot results showed that the key factors of the death receptor pathway in apoptosis fas, fas-L, and caspase-8 were activated during storage of the meat. Treatment with ultrasound significantly stimulated the activity of caspase-9, cytochrome c and tbid, and increased the ratio of bax/bcl-2 as shown by western blotting analysis. Transmission electron microscopy images showed ultrastructural damage to the mitochondria and nucleus that was morphologically characteristic of apoptosis during post-mortem ageing. All the treatments reduced the band intensity of desmin and caspase-3 during 5 days of meat ageing. The hematoxylin-eosin staining of muscle tissue structure showed that ultrasound treatment increased the gap between muscle fibre bundles. Ultrasonic treatment significantly reduced the shear force of chicken breast, which could improve the tenderness of the meat. The findings of this investigation revealed that ultrasound affected meat ageing via apoptosis and possibly activated myofibril degradation. We speculate that the morphological and biochemical changes relating to apoptosis have the potential to contribute to the tenderization of meat.

Impact of malondialdehyde (MDA) and (−)-Epigallocatechin-3-gallate (EGCG) on gelling properties of myofibrillar proteins (MPs) was investigated. Addition of 6 mM MDA enhanced molecular interactions of proteins, thus the strength and elastic modulus (G′) of gel were improved. EGCG addition aggravated gel quality deterioration due to further modification of MPs induced by EGCG. Addition of 12 mM MDA jeopardized gel quality according to the increasing of strength and G′, but the decreasing of water-holding capacity (WHC), and the collapse of microstructure. Nevertheless, EGCG reacted with MDA forming EGCG-MDA adducts, hence improved gel quality, which was supported by the decreasing of strength, but the increasing of WHC, and the repaired microstructure of gel at 12 mM MDA. Addition of 24 mM MDA severely jeopardized gel quality, which became even worse due to EGCG addition. This work is helpful to understand the impact of MDA and polyphenols on the gel-forming capacity of MPs.

Resveratrol supplementation has been reported to improve markers of vascular function, but poor bioavailability of the parent compound is thought to limits its use. In this study, we compared the effects of a resveratrol-arginine conjugate (ResArg) to trans-resveratrol (trans-Res), the standard form used in supplements, on measures of microvascular function 1 h and 2 h after intake. Postmenopausal women were assigned to consume 90 mg of resveratrol as either ResArg or t-Res, in a double-blind, randomized, crossover design, at least one week apart. Microvascular function was assessed by peripheral arterial tonometry, and calculated as the reactive hyperemia index (RHI) and the Framingham RHI (fRHI); at 1 h, platelet reactivity, plasma resveratrol and nitrate/nitrite levels were also measured. A significant increase in fRHI was observed 1 h after intake of ResArg compared to trans-Res. Significant reductions in platelet reactivity were noted 1 h after ResArg intake, but not for trans-Res. Plasma resveratrol levels were increased 30 and 60 min after the consumption of both ResArg and t-Res. The results suggest a more rapid and pronounced response from ResArg than trans-Res on certain markers of vascular function.

Different effects of lamb and pork consumption on thyroid hormone levels and energy metabolism of rats were investigated. Three diets, a lamb meat diet (LD), a pork meat diet (PD) and control casein diet (CD) were isocaloric (15.5 kJ/g dry matters). Rats in the PD group had higher serum selenium concentrations ( P P P P P P P P P P P P