Effects of PP‐based Nanopackaging on the Overall Quality and Shelf Life of Ready‐to‐eat Salami

A total of 1% nanoclay containing polypropylene (PP)‐nanocomposite and 1% nanoclay plus 5% poly‐beta‐pinene (PβP) containing PP‐active‐nanocomposite materials were produced and tested for packaging of sliced salami. The sliced salami was packaged using both nanofilms and multilayer film of PP/PA/EVOH/PE under vacuum, modified atmosphere packaging under 50% CO₂ and 50% N₂ and air and stored at 4 °C for 90 days. During storage, headspace gas composition; microbial, physical and chemical analyses; and sensory evaluation were performed. The antimicrobial effect of PβP containing nanomaterial was pronounced under vacuum, and no bacterial growth was observed for 75 days. An a* value decreased notably in all applications during storage and preserved best by the multilayered material under vacuum and high CO₂. Thiobarbituric acid reactive substances (TBARS) were 0.63 mg MDA/kg after the processing and gradually increased at all applications during increased storage. TBARS values of all vacuum applications were lower than that of modified atmosphere packaging applications. Rancid taste development was determined by sensory panelists when TBARS values were higher than 0.80 mg MDA/kg on the 90th day. There was no significant moisture loss, and no increase in hardness was determined during the whole storage time. The longest shelf life was 75 days for the sliced salami under vacuum and high CO₂ using the multilayer material. PβP containing nanomaterial provided 50 days of shelf life under vacuum, which is commercially considerable. Copyright © 2017 John Wiley & Sons, Ltd.     

Wide‐spectrum antimicrobial packaging materials incorporating nisin and chitosan in the coating

Nisin and/or chitosan were coated, in 3% concentrations, onto paper with a binder medium of vinyl acetate–ethylene co‐polymer to provide antimicrobial activity for use in food packaging. The combined use of nisin and chitosan in the coating was an attempt to give a wide antimicrobial spectrum that could inhibit the growth of several food spoilage and poisonous microorganisms. The migration of the preservative from the coatings to water was evaluated at 10°C and related to the suppressed microbial growth in the water and microbial medium. After 8 days, 8.1–8.3% of nisin and 1.0–1.2% of chitosan had migrated, and the migration of each was not affected by the presence of the other. The paper coated with nisin was more effective than the chitosan‐coated paper in inhibiting the Gram‐positive bacterium, Listeria monocytogenes, whereas the latter was more effective against Escherichia coli O157:H7. Combined inclusion of nisin and chitosan in the coating gave antimicrobial activity against both bacterial strains, and could improve the microbial stability of milk and orange juice stored at 10°C. Copyright © 2003 John Wiley & Sons, Ltd.     

Use of Sodium Lactate and Modified Atmosphere Packaging for Extending the Shelf Life of Ready‐to‐Cook Fresh Meal

In this work, the combined effects of sodium lactate and modified atmosphere packaging (MAP) in extending the shelf life of a ready‐to‐cook fresh skewer, made up of raw pork chops and semi‐dried vegetable mix (i.e. zucchini, peppers and tomatoes), were investigated. In the first experimental step, a sodium lactate solution was used to dip pork chops at three different concentrations: 20, 40 and 60% w/w. The second part of the work was focused on the use of MAP. In particular, the following MAPs were tested: MA1 (50%O₂/30%CO₂/20%N₂), MA2 (70%O₂/30%CO₂), MA3 (30%O₂/70%CO₂) and MA4 (30%O₂/30%CO₂/40%N₂). Finally, the optimal concentration of sodium lactate and the best gas composition were combined. The samples were stored at 4 °C; their microbial and sensory qualities were monitored along the entire observation period. The results indicate that the shelf life of the investigated ready‐to‐cook meal can be extended by approximately 83%, if compared with the control skewer packaged in air. The best preservation strategy is the combination of dipping of meat pieces in 40% sodium lactate solution and packaging under MA1. Copyright © 2014 John Wiley & Sons, Ltd.     

Influence of Active Packaging on the Shelf‐life­ of Minimally Processed Fish Products in a Modified Atmosphere

The effectiveness of an innovative foam plastic tray, provided with absorbers for volatile amines and liquids, on the shelf‐life of different fish products packed under a modified atmosphere (40%CO₂:60%N₂), was evaluated in comparison with a standard tray. Fillets of sole (Solea solea), steaks of cod (Merluccius merluccius) and whole cuttlefish (Sepia fillouxi), placed in the two different kinds of trays, were kept at 3°C. Microbiological (TBC‐, Gram‐negative‐, H₂S‐producing bacteria and lactic acid bacteria) and chemical (surface pH, TMA headspace) analyses were carried out after 3, 7 and 10 days of storage. The new packaging, associated with a rigorous control of storage temperature, increased the shelf‐life up to 10 days. In fact, the innovative tray sequestrated the greater part of trimethylamine from the headspace and led to delayed microbial growth, especially of Gram‐negative and H₂S‐producing bacteria, and in addition it favoured the growth of bacterial strains such as Moraxella phenylpiruvica , which are not involved in off‐flavouring production (especially H₂S), because of their lypolitic activity. Copyright © 2001 John Wiley & Sons, Ltd.     

Effect of Pretreatment and Modified Atmosphere Packaging on Quality of dry Coleslaw mix

The aim of the study was to determine the effect of soaking in chlorinated water (100 ppm chlorine) or mild thermal treatment in water (55°C; 3 min) and modified atmosphere packaging on the quality and shelf life of dry coleslaw stored for 12 days at 4°C. Samples were packaged in low‐barrier film in modified atmosphere containing: 5/10/85, 20/25/55, 50/30/20, 70/30/0 %O₂/% CO₂/% N₂, and air atmosphere. In‐pack gas levels, sensory quality, microbial counts and cell permeability were determined. In comparison to non‐processed coleslaw, pretreatment of coleslaw, both consisting in soaking in chlorine solution and a mild thermal processing, resulted in a reduction by approx. 1 logarithmic cycle for counts of psychrophilic and lactic acid bacteria as well as mesophilic and psychrophilic yeasts, by 1 and 1.7 logarithmic cycle for coliform bacteria and by 2 up to 3 logarithmic cycles for Pseudomonas bacteria. Modified atmosphere (irrespective of its composition) used in product packaging was found to have no effect on the count of mesophilic bacteria. An elevated content of carbon dioxide in modified atmosphere (10, 25 or 30%) inhibited growth of psychrophilic bacteria and Pseudomonas bacteria up to 6 days of storage. In the case of coliform bacteria growth inhibition during storage was recorded both in the samples packaged in air atmosphere and in the atmosphere of 50/30/20 and 70/30/0 %O₂/% CO₂/% N₂. In samples packaged in the atmosphere of 70% O₂ and 30% CO₂ after 12 days the greatest cell permeability was recorded, which was connected with a deterioration of their microbiological quality. Copyright © 2015 John Wiley & Sons, Ltd.     

Quality changes of treated fresh‐cut tropical fruits in rigid modified atmosphere packaging containers

There has been increasing demand for various fresh‐cut tropical fruits. However, their short shelf‐life has limited the market increase of this product. Quality changes (firmness, colour, total soluble solids (TSS), titratable acidity (TA), sensory quality and microbial safety) of fresh‐cut mangoes, pineapples, melons and mixes of these fruits were evaluated. Chemical treatments to reduce browning, firmness loss and decay of fresh‐cut tropical fruits were investigated. The most effective agents for fresh‐cut mangoes, pineapples and melons were 0.1m ascorbic acid, 0.2m ascorbic acid and 0.2m ascorbic acid + 0.2m calcium chloride, respectively. Fresh‐cut tropical fruits were packaged in various rigid containers (PET, OPS and OPLA). Gas composition in the package headspace and time to reach steady‐state condition varied among fresh‐cut packaging systems and affected their quality and shelf‐life. The effects of package permeability of O₂ and CO₂ on quality and shelf‐life of the fresh‐cut products are discussed. Extended shelf‐life was observed in fresh‐cut mangoes, pineapples and mixes packaged in PET due to reduced O₂ and elevated CO₂ atmosphere. A modified atmosphere of 6% O₂ and 14% CO₂ achieved in PET extended the shelf‐life of fresh‐cut pineapples from 6 to 13 days. Accumulation of CO₂ may impart an off‐odour of fresh‐cut fruits. The results suggested that the shelf‐life of fresh‐cut fruits could be extended by using proper rigid containers. Suitable mixes to create optimal equilibrium modified atmosphere had a potential to extend shelf‐life of short shelf‐life fresh‐cut tropical fruits. Copyright © 2006 John Wiley & Sons, Ltd.     

Composites of Bacterial Cellulose and Small Molecule‐Decorated Gold Nanoparticles for Treating Gram‐Negative Bacteria‐Infected Wounds

Bacterial infections, especially multidrug‐resistant bacterial infections, are an increasingly serious problem in the field of wound healing. Herein, bacterial cellulose (BC) decorated by 4,6‐diamino‐2‐pyrimidinethiol (DAPT)‐modified gold nanoparticles (Au‐DAPT NPs) is presented as a dressing (BC‐Au‐DAPT nanocomposites) for treating bacterially infected wounds. BC‐Au‐DAPT nanocomposites have better efficacy (measured in terms of reduced minimum inhibition concentration) than most of the antibiotics (cefazolin/sulfamethoxazole) against Gram‐negative bacteria, while maintaining excellent physicochemical properties including water uptake capability, mechanical strain, and biocompatibility. On Escherichia coli‐ or Pseudomonas aeruginosa‐infected full‐thickness skin wounds on rats, the BC‐Au‐DAPT nanocomposites inhibit bacterial growth and promote wound repair. Thus, the BC‐Au‐DAPT nanocomposite system is a promising platform for treating superbug‐infected wounds.     

Effect of Different Packaging Methods on Quality and Shelf Life of Fresh Reindeer Meat

The impact of different packaging methods [vacuum, modified atmosphere packaging (MAP) (60% CO₂ and 40% N₂) and MAP + CO₂ emitter] on the quality of fresh reindeer meat (M. semimembranosus) stored at 4°C for 21 days was investigated. Colour and odour of the meat, drip loss, pH, microbial content, antioxidant capacity and cooking loss were measured. The MAP + CO₂ emitter resulted in prolonged microbial shelf life compared with vacuum and MAP without CO₂ emitter as lower level of total viable counts was detected after 13 and 17 days. Samples stored with CO₂ emitter also had lower drip loss. Samples stored in vacuum had significant lower L*‐value, higher a*‐value and lower intensity of freshness (odour and colour) compared with those stored in MAP and MAP with CO₂ emitter. However, MAP with a gas‐to‐product volume ratio of 1 : 1 seems to be too low in quality preserving. Increased partial pressure by adding a CO₂ emitter improved bacterial inhibition compared with vacuum and traditional MAP. Copyright © 2014 John Wiley & Sons, Ltd.     

Porous Ultrahigh Gas‐Permeable Polypropylene Film and Application in Controlling In‐pack Atmosphere for Asparagus

Porous polypropylene (PP) films with greater gas permeability and lower permeability ratios (β) than existing commercial films were developed for fresh produce packaging. PP containing high content of beta‐form crystal was biaxially stretched under controlled conditions. Resulting porous films with uniquely high oxygen transmission rate (OTR) of 2 659 000 cm³?m^?2?d^?1, water vapor transmission rate of 67 g?m^?2?d^?1, and β value of 0.76 was used as a “breathable window” attached to the less permeable commercial BOPP (biaxially oriented PP) lidding film. Various sizes/areas of the breathable windows were designed and tested on packaging asparagus of 400 g, at 5°C. Results demonstrated that in‐pack O₂ and CO₂ concentrations could be practically controlled and modified by changing areas of the breathable windows. Altered porous high OTR area directly affected total gas permeation of the package. Optimum gas composition of Ο₂ and CΟ₂ within the recommended controlled atmosphere for asparagus, stored at 5°C, was effectively created and maintained in the package containing 25 cm² breathable window (15% of total film lid's area). The shelf life of asparagus under optimum modified atmosphere was extended to 29 days, as compared with <3 days in the normal, low OTR tray sealed with BOPP lidding film. Clearly, these developed porous ultrahigh permeable PP films can be useful materials in designing high OTR package with desirable in‐pack O₂ and CO₂ concentrations. Copyright © 2013 John Wiley & Sons, Ltd.     

A Multi‐functional Biofilm Used as an Active Insert in Modified Atmosphere Packaging for Fresh Produce

We developed a multi‐functional agar‐based biofilm for fresh produce packaging by modulating its CO₂ absorption and water vapour absorption functions. The film was prepared from solutions containing agar as a matrix and a water vapour absorbent, glycerol as a plasticizer, and sodium carbonate (SC) and/or sodium glycinate (SG) as a CO₂ absorbent. The optical, mechanical, and CO₂ and water vapour absorption properties of SC, SG, and SC/SG films were investigated. Multi‐functional films tended to show poor mechanical properties, with a hard texture and an opaque and yellowish colour. The three films had different CO₂ absorption capacities and coefficients, with SC film showing the highest absorption, followed by SC/SG and SG films. The water absorption coefficients were much higher than those of CO₂, with the opposite dependence on the absorbent compound. The multi‐functional benefits of the developed film were shown by using the film for modified atmosphere packaging (MAP) of shiitake mushrooms as an insert label. A tailored MAP design for shiitake mushrooms was produced based on mass transfer mathematical models. The package attached with SC film label was capable of generating the desired internal atmosphere and thus showed the best quality preservation in terms of colour, firmness, flavour score, and bacterial growth after 5‐day storage. A tailored MAP system with our multi‐functional film can provide an optimal modified atmosphere for CO₂‐sensitive fresh commodities, preserve their quality, and extend their shelf life. Copyright © 2015 John Wiley & Sons, Ltd.     

High‐Temperature Corrosion of NiTi‐Shape‐Memory Alloys

Semi‐finished products and components made of NiTi‐shape‐memory alloys (NiTi‐SMA) are often subjected to heat treatment after their fabrication. During this heat treatment, oxide layers begin to form which contain a high amount of titanium. In this investigation special attention was drawn to the selective oxidation of Ti because a TiO_X‐layer can represent a Ni‐barrier and may therefore be of special use for medical applications. A comparison of the following three samples was carried out: A sample oxidised at room temperature, another that was heat‐treated in ambient air (600 °C/1min) and a third sample that was subjected to a heat treatment (600 °C/1min) in an atmosphere that oxidises titanium but reduces NiO in order to achieve a selective oxidation of the titanium. The analysis of the oxide layers was carried out by means of x‐ray photoelectron spectroscopy (XPS). It was shown that the ratio of titanium to nickel in the oxide layer can be substantially increased when performing the annealing treatments in a partial reducing atmosphere. Furthermore, a thermo‐gravimetric investigation of the material was carried out at 600 °C in dry air in order to estimate the growth of the oxide layers.     

Electrophoretic Deposited Stable Chitosan@MoS2 Coating with Rapid In Situ Bacteria‐Killing Ability under Dual‐Light Irradiation

Developing in situ disinfection methods in vivo to avoid drug‐resistant bacteria and tissue toxicity is an urgent need. Here, the photodynamic and photothermal properties of the chitosan‐assisted MoS₂ (CS@MoS₂) hybrid coating are simultaneously inspired to endow metallic Ti implants with excellent surface self‐antibacterial capabilities. This coating, irradiated by only 660 nm visible light (VL) for 10 min, exhibits an antibacterial efficacy of 91.58% and 92.52% against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), respectively. The corresponding value is 64.67% and 57.44%, respectively, after irradiation by a single 808 nm near infrared light for the same amount of time. However, the combined irradiation using both lights can significantly enhance the efficiency up to 99.84% and 99.65% against E. coli and S. aureus, respectively, which can be ascribed to the synergistic effects of photodynamic and photothermal actions. The former produces single oxygen species under 660 nm VL while the latter induces a rise in temperature of implants, which can inhibit the growth of both E. coli and S. aureus. The introduction of CS can also promote the biocompatibility of implants, which provides a facile, rapid, and safe in situ bacteria‐killing method in vivo without needing a second surgery.     

Exploiting Propolis as an Antimicrobial Edible Coating to Control Post‐harvest Anthracnose of Bell Pepper

The application of ethanolic extracted propolis (EEP) as a food coating for bell pepper was evaluated by assessing its ability to inhibit mycelial growth of Colletotrichum capsici and maintain the post‐harvest quality of bell pepper. Propolis was extracted with ethanol, and its efficacy in the inhibition of mycelial growth of C. capsici, the causal agent of anthracnose in bell pepper, was assessed in vitro and in vivo. Mycelial growth inhibition was positively related to the EEP concentration with inhibition values reported for 0.25%, 0.50% and 0.75% EEP dilutions as 66.1%, 84.3% and 89%, respectively. Meanwhile, for in vivo studies, 1%, 5% and 10% EEP dilutions were used, which were all found to completely inhibit anthracnose development in artificially inoculated bell peppers stored at 10°C and 90% relative humidity for 28 days. The application of EEP as a coating significantly reduced the incidence of disease and contributed towards moisture retention of the fruit. These factors play a major role in the maintenance of quality of fruits and extended shelf life. Copyright © 2014 John Wiley & Sons, Ltd.     

Low‐density Polyethylene Films Loaded by Titanium Dioxide and Zinc Oxide Nanoparticles as a New Active Packaging System against Escherichia coli O157:H7 in Fresh Calf Minced Meat

Antibacterial packaging is introduced as a new method to prevent microbial food spoilage. Antibacterial effects of TiO₂, ZnO and mixed TiO₂–ZnO nanoparticle‐coated low‐density polyethylene (LDPE) films on Escherichia coli PTCC1330 were investigated. Bactericidal efficiency of 0.5%, 1% and 2% TiO₂ and ZnO nanoparticles and also 1% mixed TiO₂–ZnO nanoparticles with ratios of 25/75, 50/50 and 75/25 were tested under ultraviolet (UV) and fluorescent lights at two states: films alone and fresh calf minced meat packed. Maximum colony‐forming unit (CFU) reduction of 99.8% and 99.7% were obtained using 1% and 2% ZnO nanoparticle‐coated LDPE film under fluorescent light for films alone as well as 99.8% and 99.6% for fresh calf minced meat packed. 90.3% and 51.8% CFU reduction were recorded for 1% TiO₂ nanoparticle‐coated LDPE films in the presence of UV light at direct contact with bacteria and fresh calf minced meat packed, respectively. Maximum CFU reductions of 96% and 64.1% were obtained using 50/50 ratio of TiO₂/ZnO nanoparticles at the presence of UV light for film alone and fresh calf minced meat packed, respectively. ZnO nanoparticle‐coated LDPE films were identified as the best case to improve shelf life and prevent E. coli growth in fresh calf minced meat.     

Effect of packaging materials and storage conditions on bacterial growth,off‐odour,pH and colour in chicken breast fillets

A comparison was made of the effect of different packaging materials on bacterial growth, off‐odour, pH and colour of chicken breast fillets stored at 4°C. For one of the packaging materials, the effects of temperature (4°C and 8°C) and initial oxygen present (0%, 2% and 4%) on bacterial growth, off‐odour, pH and colour in chicken breast fillets were also evaluated. Chicken breast fillets stored in the packaging material with the highest oxygen transmission rate (OTR) measured at actual storage conditions had the highest bacterial growth and the highest degree of off‐odour. Chicken breast fillets stored in packaging material mainly consisting of expanded PET had similar bacterial growth and off‐odour as in the barrier display film (BDF) packages, despite a smaller headspace volume and lower initial concentration of CO₂. No differences in discoloration and pH of the chicken breast fillets, due to storage temperature and amount of initial oxygen present, were found when one of the packaging materials was studied. In the early phase of the storage period, Pseudomonas spp. constituted the majority of the total viable counts, while after about 12 days, lactic acid bacteria dominated. At the end of the storage period, both Pseudomonas spp. and Enterobacteriaceae were present in high numbers. Significant differences in counts of Brochothrix thermosphacta were only obtained with initial presence of oxygen. The storage temperature had greater impact on microbial growth and off‐odour than the initial presence of oxygen in the packages. Copyright © 2004 John Wiley & Sons, Ltd.     

Air‐Processed,Stable Organic Solar Cells with High Power Conversion Efficiency of 7.41%

High efficiency, excellent stability, and air processability are all important factors to consider in endeavoring to push forward the real‐world application of organic solar cells. Herein, an air‐processed inverted photovoltaic device built upon a low‐bandgap, air‐stable, phenanthridinone‐based ter‐polymer (C₁₅₀H₂₁₈N₆O₆S₄)_n (PDPPPTD) and [6,6]‐phenyl‐C₆₁‐butyric acid methyl ester (PC₆₁BM) without involving any additive engineering processes yields a high efficiency of 6.34%. The PDPPPTD/PC₆₁BM devices also exhibit superior thermal stability and photo‐stability as well as long‐term stability in ambient atmosphere without any device encapsulation, which show less performance decay as compared to most of the reported organic solar cells. In view of their great potential, solvent additive engineering via adding p‐anisaldehyde (AA) is attempted, leading to a further improved efficiency of 7.41%, one of the highest efficiencies for all air‐processed and stable organic photovoltaic devices. Moreover, the device stability under different ambient conditions is also further improved with the AA additive engineering. Various characterizations are conducted to probe the structural, morphology, and chemical information in order to correlate the structure with photovoltaic performance. This work paves a way for developing a new generation of air‐processable organic solar cells for possible commercial application.     

Antimicrobial Activity of Cinnamaldehyde and Eugenol and Their Activity after Incorporation into Cellulose‐based Packaging Films

Cinnamaldehyde and eugenol were investigated for their antimicrobial activity against 10 pathogenic and spoilage bacteria and three strains of yeast, using an agar‐well diffusion assay. The minimum inhibitory concentrations (MICs) of these compounds were determined using an agar dilution method. Finally, cinnamaldehyde‐incorporated and eugenol‐incorporated methyl cellulose films were prepared to obtain active antimicrobial packaging materials. These antimicrobial cellulose‐based packaging films were investigated for antimicrobial activity against target microorganisms using both an agar‐disc diffusion technique and a vapour diffusion technique. At a concentration of 50 µl/ml, cinnamaldehyde and eugenol revealed antimicrobial activity against all test strains. They showed zones of inhibition, ranging from 8.7 to 30.1 mm in diameter. Eugenol and cinnamaldehyde possessed ‘moderate?strong inhibitory’ and ‘strong?highly strong inhibitory’ characteristics, respectively. With MICs of 0.78?50 µl/ml, cinnamaldehyde and eugenol also inhibited the growth of all test microorganisms. Among the test microorganisms, Aeromonas hydrophila and Enterococcus faecalis were the most sensitive to cinnamaldehyde and eugenol. Cinnamaldehyde showed lower MICs against all test strains than those of eugenol. In an agar‐disc diffusion assay, cellulose‐based film containing cinnamaldehyde or eugenol totally failed to exhibit a clear inhibitory zone. However, it showed positive activity against all selected test strains in terms of size and enumeration of microbial colonies in a vapour diffusion assay. This study shows the potential use of cinnamaldehyde and eugenol for application in antimicrobial packaging film or coating. Copyright © 2011 John Wiley & Sons, Ltd.     

A Chain‐Elongated Oligophenylenevinylene Electrolyte Increases Microbial Membrane Stability

A novel conjugated oligoelectrolyte (COE) material, named S6 , is designed to have a lipid‐bilayer stabilizing topology afforded by an extended oligophenylenevinylene backbone. S6 intercalates biological membranes acting as a hydrophobic support for glycerophospholipid acyl chains. Indeed, Escherichia coli treated with S6 exhibits a twofold improvement in butanol tolerance, a relevant feature to achieve within the general context of modifying microorganisms used in biofuel production. Filamentous growth, a morphological stress response to butanol toxicity in E. coli, is observed in untreated cells after incubation with 0.9% butanol (v/v), but is mitigated by S6 treatment. Real‐time fluorescence imaging using giant unilamellar vesicles reveals the extent to which S6 counters membrane instability. Moreover, S6 also reduces butanol‐induced lipopolysaccharide release from the outer membrane to further maintain cell integrity. These findings highlight a deliberate effort in the molecular design of a chain‐elongated COE to stabilize microbial membranes against environmental challenges.     

Effect of modified atmosphere packaging and superchilled storage on the shelf‐life of farmed ready‐to‐cook spotted wolf‐fish (Anarhichas minor)

Modified atmosphere packaging (MAP) combined with superchilling (?1°C) was evaluated as a mild preservation method for farmed spotted wolf‐fish (Anarhichas minor). Portions were packaged in air and in CO2:N2 (60%:40%) atmosphere with a gas:product ratio of approximately 1, at superchilled (?1.0°C ± 0.2°C) or chilled (+4.0°C ± 0.2°C) temperatures. A reduced bacterial growth (p < 0.001), measured as aerobic plate counts (APC) and psychrotrophic bacteria, was observed in modified atmosphere (MA) packaged wolf‐fish at both ?1°C and +4°C, compared to portions in air. MA‐packaged wolf‐fish had improved odour and flavour scores (p < 0.05), but also a higher drip loss than fish stored in air. A shelf‐life of 15 days was obtained at ?1°C for MA‐packaged fish compared to 8–10 days in air, and at 4°C the shelf‐life was 13 days in MA and 6–8 days in air. Copyright © 2006 John Wiley & Sons, Ltd.     

Ethanol vapour sensing properties of screen printed WO<Subscript>3</Subscript> thick films

This paper presents ethanol vapour sensing properties of WO₃ thick films. In this work, the WO₃ thick films were prepared by standard screen-printing method. These films were characterized by X-ray diffraction (XRD) measurements and scanning electron microscopy (SEM). The ethanol vapour sensing properties of these thick films were investigated at different operating temperatures and ethanol vapour concentrations. The WO₃ thick films exhibit excellent ethanol vapour sensing properties with a maximum sensitivity of ∼1424.6% at 400°C in air atmosphere with fast response and recovery time.