Quality and Nutritional Minerals in Chicken Breast Muscle Treated with Low and High Pulsed Electric Fields

The present research investigated the effects of pulsed electric fields (PEF), low PEF (LPEF, 2.5 kV, 200 Hz and 20 μs) and high PEF (HPEF, 10 kV, 200 Hz and 20 μs), on the quality of chicken breast at 1 and 4 days post-treatment and on the concentrations of minerals (phosphorus, iron, zinc and potassium) in raw and cooked samples. HPEF increased (P < 0.001) the temperature of the chicken breasts. The shear force of chicken breasts was not affected by treatment and post-treatment storage time and their interaction (P > 0.05). The concentrations of P, K, and Zn were decreased by cooking (P < 0.001) only. The concentration of Fe was not affected by treatment, storage time, or cooking. Both LPEF and HPEF treatments did not have negative effects on the quality of chicken breast, indicating that PEF processing of chicken breast does not have a negative impact on the quality.     

Viability of Salmonella enterica subsp. enterica during the preparation and cold storage of Egyptian soft cheeses and ice-cream

Changes occurring in the viability of Salmonella enterica subsp. enterica during the preparation and cold storage of Domiati cheese, Kariesh cheese and ice-cream were examined. A significant decrease in numbers was observed after whey drainage during the manufacture of Domiati cheese, but Salmonella remained viable for 13 weeks in cheeses prepared from milks with between 60 and 100 g/L NaCl; the viability declined in Domiati cheese made from highly salted milk during the later stages of storage. The method of coagulation used in the preparation of Kariesh cheese affected the survival time of the pathogen, and it varied from 2 to 3 weeks in cheeses made with a slow-acid coagulation method to 4–5 weeks for an acid-rennet coagulation method. This difference was attributed to the higher salt-in-moisture levels and lower pH values of Kariesh cheese prepared by the slow-acid coagulation method. A slight decrease in the numbers of Salmonella resulted from ageing ice-cream mix for 24 h at 0°C, but a greater reduction was evident after one day of frozen storage at −20°C. The pathogen survived further frozen storage for four months without any substantial change in numbers.     

Ozone treatment ameliorates oil sands process water toxicity to the mammalian immune system

We evaluated whether ozonation ameliorated the effects of the organic fraction of oil sands process water (OSPW) on immune functions of mice. Ozonation of OSPW eliminated the capacity of its organic fraction to affect various mouse bone marrow-derived macrophage (BMDM) functions in vitro. These included the production of nitric oxide and the expression of inducible nitric oxide synthase, the production of reactive oxygen intermediates and the expression of NADPH oxidase subunits, phagocytosis, and the expression of pro-inflammatory cytokine genes. Ozone treatment also eliminated the ability of OSPW organic fraction to down-regulate the expression of various pro-inflammatory cytokine and chemokine genes in the liver of mice, one week after oral exposure. We conclude that ozone treatment may be a valuable process for the remediation of large volumes of OSPW.     

Oxidation kinetics of two pesticides in natural waters by ozonation and ozone combined with hydrogen peroxide

The oxidation of bromoxynil and trifluralin was investigated using ozone (O₃) and O₃ combined with hydrogen peroxide (H₂O₂) in natural waters using batch reactors. The results indicated that these pesticides could not be completely degraded during ozonation, achieving degradation levels lower than 50%. An enhancement of the level of degradation was observed using O₃/H₂O₂ process. A biphasic behaviour of O₃ was also observed. Depending on the experimental conditions, the rate constant for O₃ decomposition was estimated to be between 7.4 × 10⁻⁴ s⁻¹ to 5.8 × 10⁻² s⁻¹, and 3.2 × 10⁻³ s⁻¹ to 4.2 × 10⁻² s⁻¹ for bromoxynil and trifluralin samples, respectively. Acute toxicity analysis performed using Microtox^® showed a decrease in the toxic effects of the samples on the luminescent bacteria during the first few minutes of treatment, followed by an increase of the toxic effects at the end of the reaction for both pesticides. The quantification of oxidation by-products generated during treatment was also addressed. The total molar balances of the degradation by-products versus the initial pesticide concentrations ranged from 60 to 103% under different experimental conditions.     

Synthesis and characterization of high molecular weight hydrophobically modified polyacrylamide nanolatexes using novel nonionic polymerizable surfactants

In this article, nine hydrophobically modified polyacrylamides (HM-PAM) nanolatexes, were synthesized by copolymerizing the acrylamide monomer and novel polymerizable surfactants (surfmers). The reaction was carried out by inverse microemulsion copolymerization technique. The copolymerization was initiated by redox initiators composed of potassium peroxodisulphate and sodium bisulfite. The emulsion was stabilized using mixed tween 85 and span 80 as nonionic emulsifiers. The prepared HM-PAMs were classified into three groups according to the surfmers used in the copolymerization. The chemical structures of the prepared HM-PAMs were confirmed by FT-IR, ¹H NMR and ¹³C NMR. The thermal properties were estimated with the thermal gravimetric analysis (TGA). The size and morphology of the prepared latexes were investigated by the dynamic light scattering (DLS) and the High Resolution Transmission Electron Microscope (HRTEM). Finally, the molecular weights of the prepared copolymers were determined by the GPC and the viscosity average molecular weight method. They were situated between 1.58 × 10⁶ and 0.89 × 10⁶.     

High-pressure processing of fish and shellfish products: Safety,quality, and research prospects

Seafood products have been one of the main drivers behind the popularity of high-pressure processing (HPP) in the food industry owing to a high demand for fresh ready-to-eat seafood products and food safety. This review provides an overview of the advanced knowledge available on the use of HPP for production of wholesome and highly nutritive clean label fish and shellfish products. Out of 653 explored items, 65 articles published during 2016–2021 were used. Analysis of the literature showed that most of the earlier work evaluated the HPP effect on physicochemical and sensorial properties, and limited information is available on nutritional aspects. HPP has several applications in the seafood industry. Application of HPP (400–600 MPa) eliminates common seafood pathogens, such as Vibrio and Listeria spp., and slows the growth of spoilage microorganisms. Use of cold water as a pressure medium induces minimal changes in sensory and nutritional properties and helps in the development of clean label seafood products. This technology (200–350 MPa) is also useful to shuck oysters, lobsters, crabs, mussels, clams, and scallops to increase recovery of the edible meat. High-pressure helps to preserve organoleptic and functional properties for an extended time during refrigerated storage. Overall, HPP helps seafood manufacturers to maintain a balance between safety, quality, processing efficiency, and regulatory compliance. Further research is required to understand the mechanisms of pressure-induced modifications and clean label strategies to minimize these modifications.     

Structure-reactivity of naphthenic acids in the ozonation process

Large volumes of oil sands process-affected water (OSPW) are produced in northern Alberta by the surface mining oil sands industry. Naphthenic acids (NAs) are a complex mixture of persistent organic acids that are believed to contribute to the toxicity of OSPW. In situ microbial biodegradation strategies are slow and not effective at eliminating chronic aquatic toxicity, thus there is a need to examine alternative remediation techniques. NAs with multiple rings and alkyl branching are most recalcitrant to microbial biodegradation, but here we hypothesized that these same structural features may lead to preferential degradation in the ozonation process. Total NA degradation increased with increasing pH for commercial NA solutions, suggesting a hydroxyl radical mechanism and that naturally alkaline OSPW would unlikely require pH adjustment prior to treatment. For commercial NAs and OSPW, NAs with more rings and more carbon (and more H atoms) were depleted most rapidly in the process. Relative rate measurements with binary mixtures of model NA compounds not only confirmed this structure reactivity but also indicated that alkyl branching patterns were an additional factor determining NA reactivity. The results demonstrate that ozonation is complementary to microbial biodegradation, and the process remains a promising water reclamation strategy for the oil sands industry.     

Synthesis and evaluation of some new demulsifiers based on bisphenols for treating water-in-crude oil emulsions

The present paper endeavors to synthesize nine types of demulsifiers based on bisphenols (bisphenol A (BA), bisphenol AC (BAC) and bisphenol CH (BCH)) having different ethylene oxide units (n = 27, 34, 45) namely; E (x + y) (where E represents BA, BCH or BAC and (x + y) which represents the ethylene oxide units (27, 34, 45)). The chemical structures of the prepared demulsifier were elucidated using FT-IR and ¹H NMR spectra. Effect of the chemical structure (hydrophobic and ethoxylated degree of hydrophilic parts) and the mechanism of demulsification process was investigated. The data were discussed on the light of the chemical structure of the demulsifiers and the factors, effecting the demulsification process. The efficiency of these demulsifiers was tested on water-in-oil emulsions (w/o) at different concentrations (100, 200 and 300 ppm), 7.4% asphaltene content and 30%, 50% and 70% water content. From the obtained data the best demulsifier was E(34)BA which shows 100% demulsification after 58 min at 30% water content and 300 ppm of the demulsifier.     

Torsional effect on steel–concrete composite sections subjected to negative moment

This article summarizes the results of 13 push-out specimens under the effect of different loading combinations including shear, torsion and negative bending moment. The objective of the project is to record the reductions in the capacity of the stud shear connector and the change in the behaviour of the composite section when torsion is applied. An equation is presented to calculate the produced axial force in the stud shear connector for sections subject to any loading combination. Modifications are performed to the well-known exponential formula representing the load-slip relation of the studs. Finite element application is conducted to simulate the behaviour of the composite section and the stud shear connector as well. The simulation shows a very good agreement with the experimental results.     

水溶性非淀粉多糖的提取纯化技术进展

近几年来,植物水溶性非淀粉多糖(NSPS)在食品和医药产品中的应用取得了很大的发展,已经成为能深入研究的有趣课题。水溶性NSPS具有独特的流变特性,能够与水形成粘度由低到高的溶液,可用于饮料、烘焙、冷冻等各种食品中,以改善质地,稳定食品混合物。水溶性NSP在制药工业中也被广泛用作药物输送的封装基质,以及作为具有预防作用的生物活性材料,如抗癌和抗糖尿病。水溶性NSP在促进肠道微生物群生长和支持短链脂肪酸生产方面的益生元作用是迄今为止最有价值的科学发现。由于其使用需求不断增加,为了获得更高的得率,降低成本,缩短提取时间,扩大提取工艺规模,探索并应用了先进新颖的提取技术,包括采用超声波和微波提取水溶性NSP,克服了传统提取方法的一些局限性。为了减少损失和降低脱蛋白对提取水溶性NSP生物活性的负面影响,人们探索了绿色脱蛋白技术,如使用冻融技术替代常用的化学方法。绿色的水溶性NSP脱蛋白纯化方法将使提取的物质更安全地用于食品和医药产品中。