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The aim of this study was to determine the optimal conditions for a gliding arc plasma device using a response surface methodology and considering a low total mesophilic aerobic bacteria (TMAB) count, peroxide value (PV), colour different (ΔE), and appropriate sensory properties of stored Pacific white shrimp (PWS; Litopenaeus vannamei). A Box-Behnken design was used with three independent variables: argon gas (50–100%), treatment time (2–10 min), and distance of sample (3–7 cm). Argon gas and treatment time significantly influenced TMAB, PV, ΔE, and the sensory properties of the PWS, while sample distance had less effect. The study also revealed that the use of a high concentration (100%) of argon gas in the plasma caused a decrease in TMAB (1.2 CFU/g) compared to low concentrations (50%) of argon gas (5.41 CFU/mL). The use of a high concentration of argon gas resulted in a decrease in PV and an enhancement in ΔE and in the sensory properties of the shrimp. The results show that the use of 94.15% argon gas for 7.10 min with a sample distance of 6.54 cm provides optional gliding arc plasma conditions of 76.3% desirability. Using these numbers while maintaining PV, ΔE, and sensory properties in stored PWS caused an identical reduction of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Proteus mirabilis under in vitro and in vivo conditions. Scanning electron microscopy (SEM) analysis demonstrated that optimized plasma can destroy the cells of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Proteus mirabilis bacteria.

Response surface methodology was applied to produce synbiotic yogurt containing Lactobacillus acidophilus and flaxseed with a high probiotic count and superior physicochemical and textural properties and desirable sensory attributes. The experiments were planned using the central composite design (CCD) with two independent variables: flaxseed concentration (0–4% w/w), and storage time (1–28 days). To assess yogurt, physicochemical, textural and sensory attributes were determined and optimised. The flaxseed concentration and storage time significantly affected the viability of the L. acidophilus and the texture and sensory attributes of yogurt. This study also demonstrated that the addition of flaxseed into the probiotic yogurt caused an increase in L. acidophilus growth (up to 8.82 CFU/mL) compared to the control sample (6.87 CFU/mL) and an enhancement in the yogurt's viscosity, hardness, cohesiveness, gumminess and water holding capacity (WHC) while a decrease in yogurt's syneresis and adhesiveness occurred. At the same time, high levels of flaxseed resulted in a reduction in the yogurt's desirable sensory attributes. In general, the results of the current study indicated the addition of 4% flaxseed into probiotic yogurt could result in a functional food product with 76.8% desirability that maintains suitable properties for approximately 13 days during refrigerated storage.

In this study, flaxseed was used as a functional ingredient in yogurt formulations. The goal of this study was to produce prebiotic yogurt supplemented with flaxseed and investigation of its texture and sensory properties. Yogurt samples containing 0–4 flaxseed was produced and stored at refrigerator (4–5°C) for 28 days. Textural properties were determined by texture analysis, and sensory characteristics were assessed by 26 trained panelists. Addition of flaxseed to yogurt samples increased the hardness, gumminess, chewiness, cohesiveness, and springiness values in produced yogurt samples. However, adhesiveness level was reduced in a sample enriched with flaxseed. By increasing flaxseed concentration, the color of samples was significantly different than the control sample; L* value was diminished and a* and b* value increased. Sensory scores including taste and mouthfeel, appearance, and overall acceptance showed reduction trend in samples containing a high level of flaxseed. In general, results showed that the addition of 2.63 flaxseed into yogurt samples lead to produce functional food with satisfactory texture, sensory characteristics that sustained these properties until 17.17 days after cold storage. © 2019 The Authors. Food Science & Nutrition published by Wiley Periodicals, Inc.

International audience; One-dimensional coordination polymers constructed with the 4d metallo-ligand [Mo(NCS)6]3– associated with NiII and CoII complexes are reported. The first series consists of anionic NCS-bridged [Mo-MII]− coordination polymers associated with a discrete paramagnetic complex or a diamagnetic CoIII complex acting as cations. The latter takes advantage of the coordination preference of the S-ligand for the soft 3d ions and has led to hetero-trimetallic [MoIIINiIICoIII] and mixed valence [MoIIICoIICoIII] compounds. A second series concerns neutral chains in which trinuclear [Mo M2II] units are bridged by an additional NCS anion. The soft character of the S atom was also the key to a rare example of a compound involving both high-spin and low-spin CoII centers associated with [Mo(NCS)6]. A [Mo–Ni] derivative obtained with [Mo(NCSe)6]3– has been considered in order to evaluate the effect of Se versus S on the exchange interaction. The spin distribution for selenocyanate metallo-ligand has been assessed by density functional theory calculations. The crystal structures for all compounds have been characterized, and their magnetic behaviors have been investigated. These ferrimagnetic systems are characterized by antiferromagnetic Mo-MII interactions in the range of −40 to −90 cm–1 (based on H = −JSaSb formalism) operative both with CoII and with NiII, thus demonstrating the potential of the MoIII–NCS combination for molecular systems in which exchange interactions play an important role.