Quantifying carbon footprint of salmon fillet processed in Vietnam: impact of transportation and improvement opportunities.

The carbon footprint of a product represents the amount of greenhouse gas (GHG) emissions released during its production, transportation, and consumption and is calculated as carbon dioxide equivalent (CO2-eq). It should be integrated into different existing and future seafood awareness campaigns to create more holistic yardsticks by which consumers, retail businesses, and producers can assess the environmental impacts of seafood. This study used the life cycle assessment (LCA) method for the first time to quantify the carbon footprint of salmon fillet products processed in Vietnam for export. The carbon footprint of 1-kg salmon fillet at the factory gate ranges between 7.20 and 15.05 kg CO2-eq, depending on transportation modes of head-on-gutted (HOG) salmon from Norway to Vietnam. Transportatiton by airfreight doubled carbon footprint of salmon fillet products processed in Vietnam compared to sea freight. Feed and electricity were identified as the two most respective contributing factors during the stage of cultivation, processing fresh salmon in Norway, and the stage of salmon fillet processing in Vietnam. They accounted for about 95% and 50% of the total carbon footprint in these stages of the production chain, respectively. To reduce the carbon footprint of the salmon fillet products processed in Vietnam, the company should (i) make a careful production plan to use sea freight transportation instead of airfreight and (ii) use more electricity from renewable energy sources. Furthermore, the carbon footprint of these products can be reduced by improving the cultivation process via changing feed ingredients and enhancing the feed conversion ratio (FCR).

Curcumin-mediated photodynamic treatment extends the shelf life of salmon (Salmo salar) sashimi during chilled storage: Comparisons of preservation effects with five natural preservatives.

The impact of curcumin-mediated photodynamic treatment (PDT) on the microbiological, physicochemical and sensory qualities of salmon sashimi has not been explored. Herein, this study aimed to evaluate the effects of PDT on the shelf-life quality of ready-to-eat salmon fillets during chilled storage (4 °C) in comparison with five widely investigated natural extracts, including cinnamic aldehyde, rosmarinic acid, chlorogenic acid, dihydromyricetin and nisin. From a microbial perspective, PDT exhibited outstanding bacterial inhibition, the results of total viable counts, total coliform bacteria, psychrotrophic bacteria, Pseudomonas spp., Enterobacteriaceae family, and H2S-producing bacteria were notably inactivated (p < 0.05) to meet the acceptable limits by PDT in comparison with those of the control group and natural origin groups, which could extend the shelf-life of salmon fillets from<6 days to 10 days. In the alteration of physicochemical indicators, PDT and natural extracts were able to maintain the pH value and retard lipid oxidation in salmon fillets, while apparently slowing the accumulation (p < 0.05) of total volatile basic nitrogen and biogenic amines, especially the allergen histamine, which contrary to with the variation trend of spoilage microbiota. In parallel, PDT worked effectively (p < 0.05) on the breakdown of adenosine triphosphate and adenosine diphosphate to maintain salmon fillet freshness. Additionally, the physical indicators of texture profile and color did not have obvious changes (p < 0.05) after treated by PDT during the shelf life. Besides, the sensory scores of salmon samples were also significantly improved. In general, PDT not only has a positive effect on organoleptic indicators but is also a potential antimicrobial strategy for improving the quality of salmon sashimi.

Electrospun chitosan-based nanofibers loading tea tree oil for fresh salmon fillet shelf-life extension.

Bioactive packaging can improve the shelf-life of food products and enhance consumer health. It can also alleviate environmental stress on the planet by reducing food waste. Here, the electrospinning of tea tree oil-loaded 2-hydroxypropyltrimethyl ammonium chloride chitosan nanofibers was investigated. The fabricated nanofiber films were characterized by scanning electron microscopy, thermal gravimetric analysis, Fourier transform infrared spectroscopy, and contact angle meter analysis. The prepared nanofibers have a well-defined diameter of about 200 nm and a smooth shape. They have good antibacterial properties against Staphylococcus aureus and Escherichia coli in vitro. Tea tree oil-loaded chitosan-based nanofibers were found to be effective in delaying spoilage and extending the shelf life of salmon by sensory evaluation, texture analysis, color, total viable counts, thiobarbituric acid, and total volatile basic nitrogen during storage in the freshness experiments, thus indicating their health benefits in bioactive packaging.

Fabrication and characterization of hybrid eco-friendly high methoxyl pectin/gelatin/TiO2/curcumin (PGTC) nanocomposite biofilms for salmon fillet packaging.

Hybrid eco-friendly nanocomposite films were fabricated by blending high-methoxyl pectin, gelatin, TiO2, and curcumin through the solution casting method. Various concentrations (0-5 wt%) of TiO2 nanoparticles (TNPs) and curcumin as an organic filler were added to the blend solutions. A high TNP concentration affected the surface morphology, roughness, and compactness of the films. Additionally, 3D mapping revealed the nanoparticle distribution in the film layers. Moisture content, water solubility, and light transmittance reduced dramatically with increasing TNP content, in accordance with the water vapor and oxygen permeabilities. X-ray diffraction revealed that the films were semicrystalline nanocomposites, and the thermal properties of the films increased when 5 wt% of TNPs was incorporated into the blend solution. Fourier-transform infrared and Raman analyses revealed interactions among biopolymers, nanoparticles, and organic fillers through hydrogen bonding. The shelf life of fresh salmon fillets was prolonged to six days for all groups, revealed by total viable counts and psychrotrophic bacteria counts, and the pH of the salmon fillets could be extended until the sixth day for all groups. Biodegradation assays demonstrated a significant weight loss in the nanocomposite films. Therefore, a nanocomposite film with 5 wt% TNPs could potentially be cytotoxic to NIH 3T3 cells.

On-site Direct Detection of Astaxanthin from Salmon Fillet Using Raman Spectroscopy.

A new technology employing Raman spectroscopy is attracting attention as a powerful biochemical technique for the detection of beneficial and functional food nutrients, such as carotenoids and unsaturated fatty acids. This technique allows for the dynamic characterization of food nutrient substances for the rapid determination of food quality. In this study, we attempt to detect and measure astaxanthin from salmon fillets using this technology. The Raman spectra showed specific bands corresponding to the astaxanthin present in salmon and the value of astaxanthin (Raman band, 1518 cm-1) relative to those of protein/lipid (Raman band, 1446 cm-1) in the spectra increased in a dose-dependent manner. A standard curve was constructed by the standard addition method using astaxanthin as the reference standard for its quantification by Raman spectroscopy. The calculation formula was established using the Raman bands typically observed for astaxanthin (i.e., 1518 cm-1). In addition, we examined salmon fillets of different species (Atlantic salmon, coho salmon, and sockeye salmon) and five fillets obtained from the locations (from the head to tail) of an entire Atlantic salmon. Moreover, the sockeye salmon fillet exhibited the highest astaxanthin concentration (14.2 mg/kg), while coho salmon exhibited an intermediate concentration of 7.0 mg/kg. The Raman-based astaxanthin concentration in the five locations of Atlantic salmon was more strongly detected from the fillet closer to the tail. From the results, a rapid, convenient Raman spectroscopic method was developed for the detection of astaxanthin in salmon fillets.