Search Results (443)

The growing demand for healthier and functional foods has driven the development of fish-based products enriched with natural ingredients that enhance nutritional quality and oxidative stability. This study evaluated the effect of incorporating bacupari peel flour (0, 0.75, 1.5, and 2.25%) into Nile tilapia burgers prepared from filet and mechanically separated meat. Proximate composition, antioxidant capacity (DPPH and ABTS), physicochemical and technological parameters, texture profile, microbiological safety, fatty acid profile during refrigerated storage, and sensory acceptance were determined. The flour exhibited a high fiber content (58.6%) and strong antioxidant activity (>94% inhibition for both DPPH and ABTS assays). Its inclusion significantly increased the fiber content of the burgers (from 3.23% to 6.43%), reduced pH and cooking loss, and enhanced the antioxidant capacity of the products. Changes in color and increased hardness were observed at higher inclusion levels. All treatments complied with microbiological standards and maintained acceptable sensory properties. Although an initial increase in fatty acids was observed with flour addition, a reduction occurred after 14 days of refrigerated storage. Bacupari flour demonstrated potential as a functional ingredient for nutritional enrichment and technological improvement of fish burgers. Full article

Unpasteurized fruit juices in developing countries pose significant public health risks due to potential contamination with foodborne pathogens, particularly in rural areas where reliable energy for thermal processing is lacking. This study evaluates the natural acidity of passion fruit juice as a non-thermal strategy to inactivate Salmonella ser. Typhimurium, Escherichia coli O157:H7, and Listeria monocytogenes. Pathogens were inoculated into passion fruit juice at pH 2.9, 3.4, and 3.9, and their survival was monitored at 25 °C (room temperature) and 5 °C (refrigerated). Log-linear and Weibull models were used to predict inactivation kinetics, targeting a 5-log reduction in accordance with FDA requirements. At pH 2.9 and 5 °C, S. Typhimurium and E. coli achieved a 5-log reduction within 8 h, while L. monocytogenes required 24 h to achieve the same reduction level. The Weibull model provided a superior fit (R² > 0.94) at pH 2.9 and 3.4, accurately capturing the nonlinear inactivation dynamics. Increasing pH to 3.9 significantly slowed inactivation, underscoring the critical role of low pH. These findings suggest that the inherent acidity of passion fruit juice provides a practical, energy-independent method for controlling pathogenic bacteria in developing regions, preserving nutritional quality without thermal processing. Full article

The fresh-cut avocado processing generates significant amounts of by-products, mainly peel and seed, with the peel representing a valuable source of phenolic compounds. In this context, the growing demand for sustainable technologies encourages the use of green solvents for bioactive compound recovery. In this study, natural deep eutectic solvents (NaDES) were evaluated as environmentally friendly solvents for the extraction of phenolic compounds from Hass avocado peels through ultrasound-assisted extraction and for their potential application in fresh-cut avocado. Phenolics were extracted using acidic water, ethanol, and NaDES based on choline chloride as a fixed hydrogen bond acceptor (HBA) and hydrogen bond donors (HBDs; lactic acid, glycerol, and citric acid) with the ultrasound-assisted system. The stability of the extracts was monitored for eight weeks (four weeks in darkness followed by four weeks under light exposure). Among the tested formulations, the lactic-acid-based NaDES showed the highest extraction efficiency and the best stability of phenolic compounds during storage (≥20 mg GAE g⁻¹ dw during the storage period). The lactic-acid-based extract was then applied to fresh-cut avocado to evaluate its potential for antioxidant enrichment and browning prevention during refrigerated storage. The treatment increased phenolic content and contributed to improved color stability (during seven days of storage). Overall, lactic-acid-based NaDES represent a promising green solvent system for recovering phenolics from avocado peel and for their functional application in fresh-cut avocado within a circular valorization approach. Full article

Fish-derived products are extensively acknowledged for their substantial role in fostering balanced diets and supporting a healthy way of life. This research is aimed at formulating, analyzing and evaluating a fish-based food product. The methodology adopted in this study adheres to contemporary food safety standards, prioritizing the utilization of minimal technological processes and natural ingredients, a focus that is gaining prominence within contemporary industrial practices. Thus, the proposal for a formulation obtained by integrating powders and extracts from plant byproducts (Citrus) represents a concrete application direction with real potential for commercialization. The product has been enriched with biocomponents derived from orange peel, namely orange extract (OE) and orange peel powder (PPO). The research focused on product development and the in situ evaluation of the effects of OE and PPO. The physicochemical composition, bioactive compound content, and antioxidant activity were evaluated, along with the microbiological status under post-opening refrigeration conditions, in order to simulate actual consumer use. In addition, the product’s color parameters and sensory attributes were analyzed. The results highlight significant potential for the development of a clean-label fish-based product, characterized by a simplified and easily implementable formulation, aligned with current production and consumption requirements. Compared to the control sample, both OE and PPO significantly influenced the analyzed parameters. Differences in physicochemical composition were observed in the experimental samples. In addition, PPO increased the antioxidant activity of the samples and the profile of bioactive compounds. Microbiological analysis, performed on day 0 and after 3 and 7 days of storage at 4 °C showed opening, confirmed the absence of Escherichia coli and Staphylococcus aureus in all samples and had an influence on the growth of fungi. The acceptability of fish-based products is often limited by odor perception, which is one of the main factors leading to consumer rejection. Sensory evaluation demonstrated that citrus-enriched samples were distinguished by the perception of particular sensory attributes. This formulation presents a practical solution to address this constraint, thereby enhancing the product’s sensory acceptability. The integration of OE and PPO yielded a more harmonized sensory profile, as evidenced by elevated hedonic scores and an intermediate placement in both principal component analysis (PCA) and external preference mapping. This research furnishes a thorough characterization of a fish-based food product, underscoring its potential as a viable option for balanced dietary regimens. Simultaneously, the findings support the product’s adherence to sustainability principles through the utilization of bioactive compounds sourced from plant byproducts, thus satisfying contemporary requirements for foods that possess an optimal nutritional profile and a diminished environmental footprint. Full article

Refrigeration and air-conditioning systems are vital to the global economy but contribute significantly to greenhouse gas emissions by using high-global-warming potential synthetic refrigerants. As regulatory frameworks like the Montreal Protocol, the Kigali Amendment, and the EU’s F-gas Regulations tighten, the industry faces a mandatory transition toward environmentally benign alternatives. This perspective paper evaluates the technological and environmental implications of replacing synthetic fluids with natural refrigerants, specifically ammonia, carbon dioxide, and hydrocarbons. A comparative assessment reveals that natural refrigerants offer superior thermodynamic efficiency, zero ozone depletion potential, and ultra-low global warming potential. While technologies like transcritical CO₂ and low-charge ammonia systems may involve higher initial capital costs, they increasingly achieve life cycle cost parity through improved energy performance and regulatory stability. The analysis further explores advanced cycle configurations, such as ejectors and expanders, which mitigate efficiency losses. The transition to natural refrigerants is presented as a technologically feasible and environmentally friendly strategy to mitigate the risk that rising cooling demands further accelerate climate change. Ultimately, natural refrigerants are expected to become the default global standard within the shortest feasible timeframe, with policy, industry, and research aligned to support and accelerate this transition. Full article

Growing concern over synthetic nitrite in processed meat has increased interest in natural curing alternatives for clean-label meat products. This research aimed to evaluate the potential of fermented radish and beetroot powders as natural sources of nitrite and bioactive compounds for preserving and improving the quality attributes of beef burgers during refrigerated storage. Burgers were formulated with different levels (3% and 6%) of fermented radish (R3 and R6) and beetroot (B3 and B6) and compared with negative (no additive) and positive (sodium nitrite) controls during 14 days of refrigerated storage, with physicochemical, color, oxidative, microbial, and sensory properties evaluated throughout storage. At day 7, radish and beetroot treatments improved color attributes, reduced lipid oxidation, and controlled microbial growth compared with the negative control. Among the natural treatments, R3 showed the best overall performance, with marked phenolic enrichment, high sensory scores, improved color properties, reduced lipid oxidation, enhanced DPPH radical scavenging activity, and more controlled microbial growth. Radish and beetroot treatments showed performance close to that of the positive control across most evaluated parameters, while showing higher cooking yield, higher phenolic content, greater DPPH radical scavenging activity, better consumer sensory acceptance, and lower diameter shrinkage than the positive control. Overall, the results support the potential of radish and beetroot fermented powders, especially R3, as promising clean-label alternatives for enhancing the quality and storage stability of raw beef burgers. Full article

Background: Microbial contamination of fresh beef remains a major challenge in the meat industry, driving the need for effective natural preservation strategies that can extend shelf life while meeting consumer demand. Methods: Chitosan-based edible coatings enriched with free and nanoencapsulated Ocimum basilicum L. essential oil at concentrations of 0.25%, 0.5% and 1% were evaluated for their efficacy on fresh beef during 20 days of refrigerated storage. Microbiological parameters, including total bacterial count, lactic acid bacteria, psychrotrophic bacteria, and Pseudomonas spp., as well as physicochemical indicators such as pH and thiobarbituric acid reactive substances, were monitored at regular intervals throughout storage. Results: All active coatings significantly retarded microbial growth and lipid oxidation compared to the uncoated control (p < 0.05), with effects being concentration-dependent. Nanoencapsulation was achieved with an efficiency of 74%, and all formulations consistently showed better results compared to free essential oil coatings at equivalent concentrations. Application of a chitosan coating with 1% nanoencapsulated essential oil reduced total viable count by 1.5 log CFU/g and lactic acid bacteria by 0.7 log CFU/g, with the most pronounced effect observed for Pseudomonas spp. (1.9 log CFU/g reduction). In the same sample, MDA content remained below the threshold level until the end of storage. Additionally, sensory analysis indicated that the use of nanoparticles significantly improved the overall acceptability of the coated beef. Conclusions: These findings confirm that chitosan–basil nanoparticle coatings represent a promising natural alternative to conventional preservatives for improving microbiological safety and extending the shelf life of fresh beef. Full article

Achieving stable dispersion and sustained antibacterial activity of natural bioactive compounds in bio-based packaging remains challenging. In this study, chitosan (CS) films incorporating a β-cyclodextrin–curcumin inclusion complex (Cur/β-CD) were developed to improve film properties and the refrigerated preservation of sea bass. The CS/Cur/β-CD films were prepared by one-step solution casting without intermediate isolation or purification. The inclusion conditions were optimized, and the resulting films were evaluated in terms of tensile strength (TS), elongation at break (EAB), and water vapor permeability (WVP). Among the tested formulations, the film prepared at a Cur:β-CD ratio of 1:1, 40 °C, and 1 h (1:1 40 °C 1 h) showed the best overall performance in TS, EAB, and WVP. It was therefore selected for subsequent structural characterization, antibacterial evaluation, and preservation testing. The 1:1 40 °C 1 h film exhibited a 156% increase in tensile strength and a 28.5% decrease in water vapor permeability compared with the neat CS film. The composite film exhibited measurable diffusion-based antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). During the 8 d refrigerated storage period, the film suppressed total viable counts (TVC), slowed the increase in pH, and retarded total volatile basic nitrogen (TVB-N) accumulation, thereby maintaining acceptable microbiological quality throughout the observation period. Compared with the unwrapped, PE, and CS-film control groups, the treated samples showed better preservation performance over the tested storage period. Overall, the incorporation of Cur/β-CD provides a simple strategy for improving the mechanical strength, moisture barrier properties, antibacterial activity, and preservation performance of CS films during refrigerated storage, highlighting their potential for active packaging of chilled aquatic products. Full article

The growing demand for healthier meat products has led to efforts to reduce synthetic additives, such as nitrites, in processed meats. This study evaluated the effect of enriched safflower oil with oleoresin from Capsicum annuum var. Anaheim (ESO) as a functional ingredient in the reformulation of Frankfurt-style pork sausages with reduced nitrite content. Five formulations were evaluated: a negative control without additives (F1 (0% ESO, 0% nitrite), a positive control containing only sodium nitrite F2 (0% ESO, 0.15% nitrite = 93.8 mg/kg), and three experimental treatments contained ESO and nitrite: F3 (0.5% ESO, 0.075% nitrite = 46.9 mg/kg), F4 (1% ESO, 0.05% nitrite = 31.3 mg/kg), and F5 (1.5% ESO, 0% nitrite), stored under refrigeration (4 °C) for five weeks. Physicochemical (pH, color, texture profile, proximate composition, residual chlorides and nitrites), oxidative (TBARS), and microbiological (total viable count) analyses were conducted over 5 weeks of storage. Results showed that formulation F4 provided the best balance between oxidative stability microbial control and nitrite residual content, maintaining TBARS levels below the 1.0 mg MDA/kg rancidity threshold (0.33 ± 0.01 mg MDA/kg), TVC within the 6.0 log CFU/g limit for processed meats (3.89 log CFU/g) and 1.15 mg/kg of nitrite residual at the end of the storage period. These findings suggest a synergistic effect between ESO and nitrites. Since addition of ESO was consistent with improved cured color development, likely due to the combined effect of reduced nitrite levels and the natural pigments from Anaheim chili. These findings demonstrate that ESO is a promising natural additive to partially replace nitrites, contributing to the development of healthier and safer processed meat alternatives. Full article

The paper investigates the effect of the degree of HIPS surface yellowness on its properties: colorimetric, surface, rheological, and mechanical. In order to prepare three naturally degraded samples, about 1 kg of white HIPS flakes, semi-yellow HIPS flakes, and yellow HIPS flakes, segregation based on colorimetric analysis was applied. Then, these samples were subjected to ATR-FTIR analysis, sessile drop contact angle measurements, and MFI analysis. These analyses were repeated for standardized specimens made of the segregated HIPS flakes. The average absorbances were determined for 50 HIPS samples of each type in the form flakes. Finally, mechanical tests were carried out on the standardized specimens. As follows from the research, yellowing of the HIPS surface affects the final color of the standardized specimens, which is confirmed by optical colorimetry. Moreover, material degradation demonstrated by yellowing of its surface and confirmed by a decrease in ATR-FTIR spectra absorbance, is associated with changes in mechanical and rheological properties, as well as in surface characteristics. The novelty of this study lies in the investigation of naturally degraded HIPS samples under laboratory conditions (the HIPS materials were not subjected to artificial aging using laboratory equipment), obtained from waste post-consumer cooling devices used in consumers’ homes, representing natural wear and tear of the material. The tests provide insight into both the visual and mechanical properties of components manufactured from recycled HIPS originating from degraded refrigeration equipment. They also constitute a valuable source of information for processors and manufacturers. Full article

Carbon dioxide (CO₂) hydrate slurries have emerged as promising candidates for cold thermal energy storage (CTES) and refrigeration systems due to their high latent heat, controllable flow behavior, and environmentally friendly nature. These slurries are formed by dispersing solid CO₂ hydrate particles in a liquid phase, forming a multiphase system with tunable thermophysical and rheological properties. The performance of these slurries is dependent on nucleation kinetics, particle sizes and their distribution, solid content, and thermal transport characteristics under flow conditions. This review paper gives an assessment of CO₂ hydrate slurries from a thermofluid’ perspective by focusing on key aspects such as hydrate nucleation mechanisms, viscosity behavior, shear response, thermal conductivity, convective heat transfer, and slurry stability. Particular attention is given to the role of surfactants and nanoparticle additives that enhance hydrate formation and improve slurry performance. The addition of nanofluids is discussed both in terms of their effect on thermal properties as well as in flow stability. Full article

The growing demand for sustainable food preservation drives interest in edible nanoemulsions encapsulating bioactive compounds. This study developed casein–lecithin-based nanoemulsions combining carvacrol (CV)—a compound with potent antimicrobial and moderate antioxidant activity—with vitamin E (VitE)—a powerful antioxidant—as multifunctional food coatings. Three formulations were prepared via homogenization: NE-CV (2% CV), NE-VitE (2% VitE), and NE-CV/VitE (1% each). Physicochemical characterization revealed monomodal size distributions (22.7–57.7 nm), with successful encapsulation confirmed by FTIR. NE-CV/VitE exhibited intermediate particle size (34.4 nm) and zeta potential (−19.8 mV). Antioxidant activity followed NE-VitE > NE-CV/VitE > NE-CV, with the co-encapsulated system preserving VitE’s radical scavenging (EC₅₀ 10.76 µL/mL, DPPH). Remarkably, NE-CV/VitE demonstrated enhanced antibacterial activity against E. coli, requiring half the CV concentration (0.07 mg/mL) versus NE-CV alone (0.15 mg/mL), while maintaining CV dose-dependent activity against S. aureus (0.30 mg/mL). Nanoencapsulation significantly reduced CV cytotoxicity in human lymphocytes at concentrations up to 50 μg/mL (48.8% cytostasis vs. 58.9% for free CV), with no genotoxic effects observed within this range, while preserving full bioactivity. In fresh minced pork over 6-day refrigerated storage, NE-CV/VitE coating maintained pH stability (5.65–5.75), preserved red color (a* values 6.24 vs. 4.99 uncoated), reduced lipid oxidation (TBARS 0.74 vs. 0.82 mg MDA/kg), and achieved a 99% reduction (2-log) in total viable counts versus uncoated controls. The CV/VitE co-encapsulated nanoemulsion represents an integrated, safe, and effective multifunctional preservation technology with synergistic antimicrobial enhancement and uncompromised antioxidant protection, offering a natural alternative for comprehensive food quality preservation. Full article

Protein-based hydrogels composed of gelatin, whey and glycerol were functionalized with red cabbage extract (RCE) to develop natural colorimetric pH sensors for intelligent food packaging. Structural analysis by X-ray diffraction (XRD) and scanning electron microscopy (SEM) revealed amorphous, hierarchically organized networks where RCE molecules interact with protein chains. The resulting microstructure, consisting of compact surface domains and a porous internal network, may regulate the diffusion of volatile amines into the hydrogel matrix, enabling gradual and stable pH-dependent color transitions. The resulting biocomposite hydrogel exhibited a stable and time-resolved optical response to meat spoilage, correlating structural relaxation with colorimetric sensitivity. Color difference values (ΔE₀₀) calculated based on recorded images indicated strong chromatic changes in the presence of spoilage-related volatiles. Under refrigeration, ΔE₀₀ remained below five, suggesting negligible color shifts. At room temperature, ΔE₀₀ exceeded 20 after 48 h, confirming significant anthocyanin transformation linked to increased alkalinity (pH 7.2–7.5). A positive correlation between ΔE₀₀ and pH was observed, highlighting the hydrogel’s high sensitivity to environmental changes. These findings confirm the potential of RCE-loaded hydrogels as eco-friendly, visual freshness indicators suitable for intelligent packaging applications. The hydrogel films demonstrated a distinct color transition within the pH range of 5.75–7.5, corresponding to the freshness variation interval of chicken meat. Full article

Foodborne pathogens cause hundreds of millions of illnesses annually, underscoring the urgent need for advanced antimicrobial food packaging materials. The objective of this study was to develop a crosslinked cyclodextrin metal–organic framework, loaded with gold nanoparticles (CL-AuNPs@CD-MOF) and integrated into a PLA-Zein composite film with humidity-responsive antimicrobial release, as a sustainable and high-performance packaging solution to address the critical limitations of conventional materials in controlling microbial contamination during food storage. Therefore, gold nanoparticles (AuNPs) were synthesized via a green approach using CD-MOFs as stabilizers and p-coumaric acid as a natural reducing agent, then crosslinked with diphenyl carbonate (DPC) to produce CL-AuNPs@CD-MOF. Crosslinking conditions were optimized to a CD-MOF:DPC ratio of 1:1, 1080 min reaction time, and 80 °C, preserving the cubic morphology and crystalline structure while transforming burst release into sustained antimicrobial activity against E. coli and S. aureus over 7 days. Then, the incorporation of CL-AuNPs@CD-MOF into PLA-Zein films yielded a composite packaging material with favorable mechanical and barrier properties, including a water vapor transmission rate of 539.44 g/m²·24 h and an oxygen permeability of 235.90 cm³/m²·24 h·0.1 MPa. Progressive elimination of E. coli, S. aureus, and L. monocytogenes over 7 days was confirmed, with antimicrobial efficacy originating exclusively from the CL-AuNPs@CD-MOF component. Application on Agaricus bisporus over 12 days of refrigerated storage demonstrated superior preservation performance: mushrooms inoculated with L. monocytogenes and packaged with CL-AuNPs@CD-MOF/PLA-Zein exhibited a weight loss of only 6.20 ± 2.06%, compared to 17.74 ± 3.15% for PLA-Zein and 41.50 ± 3.01% for PE controls. Color stability was equally improved, with lightness values of 71.46 ± 1.47 retained under CL-AuNPs@CD-MOF/PLA-Zein packaging, versus 58.37 ± 0.86 for PLA-Zein and 23.34 ± 2.34 for PE. Mushrooms inoculated with E. coli and S. aureus followed consistent trends. These results establish CL-AuNPs@CD-MOF/PLA-Zein as a promising multifunctional antimicrobial packaging platform for sustainable food preservation. Full article

This article presents a performance assessment of an electrical power and cooling system powered by a parabolic dish collector and using refrigerants with low global warming potential. The study was conducted using energy and mass balances for each component and system. The simulation includes various parameters, such as solar radiation, the focal temperature of the solar collector, the ambient temperature, the power cycle pressure ratio, and the chiller’s evaporation temperature. The results show that the efficiency of the organic Rankine cycle with the refrigerant R1233zd(E) is similar to that of the refrigerants R123 and R245fa and is up to 11 and 50 times lower than with R290 and R744, respectively. The solar absorption chiller using the refrigerant R717 can achieve cooling with a supply temperature up to 5 °C lower than that of R718. The dynamic simulation results show that the energy efficiency of the proposed solar-powered generator–chiller is 14% higher than that of a standard solar-powered absorption chiller. Furthermore, the same solar-powered generator–chiller reduces the primary energy required by a conventional system by 60% (PESr = 0.60). The presented results may be useful for the design of sustainable generator–chillers for rural areas or for autonomous housing in tropical climates. Full article