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In industrial applications, the potential of basalt fibre-reinforced polymer (BFRP) composite pipes as a compelling alternative to glass and carbon fibre-reinforced composite pipes is recognized. Their high recyclability makes them a viable option for aerospace, marine, and automotive applications. In this study, a comparison is made between the mechanical properties of virgin basalt–epoxy composite pipes and graphene-modified counterparts. To conduct the experiments, pipe section specimens were prepared using a flex grinding machine. Graphene nanoplatelets (GnPs), serving as an exceptional reinforcing material, were uniformly incorporated into the basalt–epoxy composites at a specific concentration. The inclusion of these nanoplatelets resulted in significant changes in mechanical stiffness compared to the virgin basalt–epoxy composite pipes. A series of tests, including uniaxial tensile, Charpy impact, microhardness, Shore D hardness, uniaxial 3-point bending, and dynamic displacement transmissibility tests, were carried out to assess the mechanical properties of both graphene-reinforced and virgin basalt–epoxy pipes. The findings indicated that the pure basalt–epoxy composite exhibited lower ductility compared to the graphene basalt–epoxy composites after undergoing uniaxial mechanical loading. Non-destructive dynamic mechanical vibration testing was used to investigate the complex mechanical response of the materials under examination. The observed complex frequency-dependent responses reflected the mutual ductile/brittle mechanical performance of the developed composites.

This article aimed to compare various mechanical properties of epoxy/graphene and epoxy/halloysite nanocomposites. Graphene nanoplatelets (GnPs) and halloysite nanotubes (HNTs) were used as fillers at different concentrations. The studied fillers were dispersed in the epoxy resin matrices. Elastic–plastic mechanical behavior modulation was observed utilizing the fillers’ nanoparticles and carboxyl-terminated butadiene–acrylonitrile copolymer rubber-modified epoxy resin. The hypothesis of the possible preceding inter-particle gliding of the individual GnPs in the complex resin nanocomposite matrix during mechanical testings was also confirmed. Increased ductility (elongation at break increased from 0.33 mm [neat matrix] to 0.46 mm [1 wt% GnPs] [39% increase]) and plasticity of the GnP nanocomposite samples were observed. In contrast, the decreasing mechanical stiffness as reflected in the decreased Young’s modulus of elasticity (from 3.4 to 2.7 GPa [20% decrease]) was found for the epoxy/HNT nanocomposites. The obtained dynamic stiffness of the investigated nanocomposites confirmed the complexity of the mechanical response of the studied material systems as a combination of the ductile and brittle phenomena.

Two different nanosized mineral fillers (nano calcium carbonate and nanoclay) were used in the high density poly(ethylene) (HDPE) composites pilot plant production. Structural and mechanical properties of the prepared composites were examined in this study. The homogenous filler distribution was confirmed in the tested samples by scanning electron microscopy, transmission electron microscopy, and energy dispersive spectroscopy analyses. The fillers’ fortifying effect on polymer composites’ mechanical performance was confirmed as indicated by the increased elastic modulus and indentation modulus. Additionally, the possible modulation of the plastic-elastic mechanical behavior was confirmed by the type of the filler as well as its concentration used in the final composites testing articles.

This paper was focused on application of the perlite mineral as the filler for polymer nanocomposites in technical applications. A strong effect of the perlite nano-filler on high-density poly(ethylene) (HDPE) composites’ mechanical and thermal properties was found. Also found was an increase of the Young’s modulus of elasticity with the increasing filler concentration. Increased stiffness from the mechanical tensile testing was confirmed by the nondestructive vibrator testing as well. This was based on displacement transmissibility measurements by means of forced oscillation single-degree-of freedom method. Fracture toughness showed a decreasing trend with increasing perlite concentration, suggesting occurrence of the brittle fracture. Furthermore, ductile fracture processes were observed as well at higher filler concentrations by means of SEM analysis. There was also found relatively strong bonding between polymer chains and the filler particles by SEM imagining.

Four different minerals were investigated; hollow spheres of calcium carbonate, platy mica, needle like wollastonite and glassy perlite and characterized via iGC for surface energy, Freeman powder rheology for flow characterization, cyclic uniaxial die compaction for modulus of elasticity and frequency dependent sound absorption properties. Particle surface energy and particle shape strongly affected the packing density of powder beds. In the case of higher porosity and thus lower bulk density, the powders acoustic absorption was higher in comparison with higher packing density materials. Surface energy profiles and surface energy distributions revealed clear convergence with powder rheology data, where the character of the powder flow at defined consolidation stresses was mirroring either the high cohesion powders properties connected with the high surface energy or powder free flowing characteristics, as reflected in low cohesion of the powder matrix.

This study comprehensively analyzes various powdered milk samples to elucidate their structural, surface, and mechanical properties. Through detailed examination, diverse characteristics among the samples were observed, shedding light on their behavior under different conditions. Notably, findings reveal intriguing insights into surface energy profiles, Harkins spreading coefficient, powder rheological properties, and sound absorption efficiency of the powdered milk samples. The intricate relationship between surface properties and bulk characteristics influenced the cooperative behavior of freely poured and consolidated milk powder beds, resulting in varying flowability from free-flowing to cohesive. Surface energy played a significant role in cohesiveness and dispersibility, with milk fat acting as a key mediator leading to changes in bulk dynamic-mechanical stiffness. These findings hold practical implications for formulating innovative aerosol-based dairy and cosmetic products, thereby enhancing everyday experiences., (© 2024, The Authors. Published by Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

This study aimed to optimize the preparation of multiple oil-water-oil (O/W/O) emulsions using varying amounts of Tween 20 emulsifier, different homogenization methods, and optimal preparation temperatures as carriers for encapsulated curcumin. Following the optimization process, the optimal preparation temperature was found to be 25 °C, with a homogenization speed of 10,000 RPM and an emulsifier concentration of 0.5% Tween 20. Subsequently, the effects of physicochemical and viscoelastic properties on the different types of oils used in the outer phase, as well as the impact of storage time, were monitored. The novelty of this work lies in its comprehensive analysis of the stability and encapsulation efficiency of multiple emulsions using various oils, an area that has not been extensively explored before. After identifying the optimal preparation procedure, all samples with different edible oils demonstrated excellent stability and encapsulation efficiency, showing minimal variation in results. The most stable multiple emulsion was found to be the one with coconut oil in the outer phase, exhibiting half the particle size compared to other samples and the lowest encapsulation efficiency losses over 50 days of storage. This study provides new insights into the formulation of stable multiple emulsions for the effective delivery of curcumin and similar bioactive compounds.

This review aims at the current trends in chocolate ganache production and recipe formulation. Ganache is a blend of chocolate, sugars, dairy, and other ingredients commonly used to fill pralines, pastries, etc. In spite of ganache's popularity in the food industry, a comprehensive review focused on the application of functional substances and ganache processing has not been discussed in the scientific literature. This review addresses the new ways of applying special ingredients, such as vegetable fats and seeds, flavor infusions, oleogels, hemp products, etc., which can be added to the ganache matrix to achieve desirable properties. In particular, the application of sterols and sterol esters as functional substances of oleogels seems to be a very promising method, enhancing the ganache fat profile. The elevated caloric content that is characteristic of ganache can be substantially attenuated through the application of hydrocolloids and/or fruit-based components, thereby offering the potential for caloric reduction without compromising on taste. The various alterations to ganache formulations by the application of natural substances offer a large base for the development of novel ganache variants and relevant food products.

Shikonin is a naphthoquinone pigment present in the hairy roots of the plant species from the Boraginaceae family. The compound has been well investigated for its highly efficient medicinal, antioxidant, and antimicrobial properties. Various extraction methodologies have been employed to maximise yield while minimising waste production of shikonin and its derivatives. Despite substantial research on shikonin and Boraginaceae plants, a research gap persists in the food industry and extraction technologies. This review addresses crucial aspects of shikonin deserving of further exploration. It begins by elucidating the attributes of the Boraginaceae plants and their medicinal traits in folklore. It proceeds to focus on the roots of the plant and its medicinal properties, followed by extraction procedures explored in the last fifteen years, emphasising the novel technologies that have been chosen to improve the yield extract while minimising extraction times. Furthermore, this review briefly outlines studies employing cell culture techniques to enhance in vitro shikonin production. Lastly, attention is directed towards research in the food industry, particularly on shikonin-loaded biodegradable films and the antioxidant activity of shikonin. This review concludes by summarising the future potential in food science and prominent research gaps in this field.

In the context of growing interest in plant-based food products for their potential health benefits and sustainability, this study investigates the effect of mono- and diglycerides of fatty acids application on physico-chemical properties of various plant-based cream products, compared to lecithin application in rice cream. Rheological and textural parameters, colour profile, and colloidal stability were analysed. The application of mono- and diglycerides modified the creams' viscoelastic behaviour, showing a decrease in viscoelasticity across the samples; although in oat-coconut cream resulted in a higher viscoelasticity, indicating the formation of a gel-like structure. Rice cream with lecithin emulsifier showed lower viscoelastic properties characterised by higher phase angle ( tan δ ). All samples behaved as pseudoplastic materials (with a flow behaviour index n < 1). For coconut and almond creams, the consistency coefficient increased and flow behaviour index decreased after emulsifier application. Interestingly, the emulsifier addition did not significantly affect the cream's colour profile, characterised by yellow hue angle ( h* ) as a dominant spectral component. The colloidal stability, indicated by a stability index ( SI ), was determined as well.

Cannabis sativa L., a plant historically utilized for textile fibers, oil, and animal feed, is progressively being recognized as a potential food source. This review elucidates the nutritional and functional attributes of hemp and cannabidiol (CBD) within the context of food science. Hemp is characterized by the presence of approximately 545 secondary metabolites, among which around 144 are bioactive cannabinoids of primary importance. The study looks in detail at the nutritional components of cannabis and the potential health benefits of CBD, encompassing anti-inflammatory, anxiolytic, and antipsychotic effects. The review deals with the legislation and potential applications of hemp in the food industry and with the future directions of cannabis applications as well. The paper emphasizes the need for more scientific investigation to validate the safety and efficacy of hemp components in food products, as current research suggests that CBD may have great benefits for a wide range of consumers.

Specialty coffees from various geographical origins were processed using different extraction methods. Four extraction techniques were employed: cold brew (CB), espresso (ES), French press (FR), and aeropress (AE). The potential health benefits of coffee brews were linked to their antioxidant activity, as determined by the DPPH assay, and total polyphenol content (TPC) measured through the Folin-Ciocalteu reducing-capacity assay. The Columbia (C) espresso coffee type (omni-roasting) exhibited the highest antioxidant activity (86.31 ± 0.70) μmol/100 mL, with a TPC value of (44.41 ± 0.35) mg GAE/g. Quantitative analyses of caffeine and chlorogenic acid were conducted using high-performance liquid chromatography (HPLC). The evaluation of coffee aroma profiles involved the application of headspace solid-phase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS) and was complemented by sensory analysis following the Specialty Coffee Association (SCA) standard protocol. The predominant volatile compounds found in all samples included furans, phenols, pyrazines, and terpenes. The EY espresso type (medium dark roasting) had the highest levels of most coffee volatiles. The C cold brew type (omni-roasting) was rated as the preferred coffee in terms of its sensory characteristics and flavour. In summary, ES and CB were found to be more effective extraction methods for the parameters assessed.

Corn silk (CS) extracts are reported to contain flavonoids (appx. 59.65 mg quercetin/g), polysaccharides (appx. 58.75 w.%), steroids (appx. 38.3 × 10 -3 to 368.9 × 10 -3 mg/mL), polyphenols (appx. 77.89 mg/GAE/g) and other functional biological substances. This study investigated the antioxidant activity of corn silk extracts related to their functional compounds. The radical scavenging effect of corn silk extracts was evaluated by the spin-trapping electron paramagnetic resonance (EPR) technique, 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzo-thiazoline-6-sulfonate) (ABTS •+ ) free radical measurement, ferric ion-reducing antioxidant power, and copper ion reductive capacity. It was found that the maturity stage of CS plant materials and the applied extraction procedure of their bioactive compounds have a profound effect on the radical scavenging capacity. Differences in the antioxidant activity of the studied corn silk samples based on their maturity were also confirmed. The strongest DPPH radical scavenging effect was observed for the corn silk mature stage (CS-M)stage (CS-MS) (65.20 ± 0.90)%, followed by the silky stage (CS-S) (59.33 ± 0.61)% and the milky stage (CS-M) (59.20 ± 0.92)%, respectively. In general, the final maturity stage (CS-MS) provided the most potent antioxidant effect, followed by the earliest maturity stage (CS-S) and the second maturity stage (CS-M).

Curcuma is a world-renowned herb known for its immense health benefits. In this study, physicochemical analyses were performed on the curcumin standard sample and curcumin multiple emulsions. The emulsions were analysed for thermal and structural stability for 21 days. Confocal laser microscopy (CLSM) was performed in order to observe the emulsion encapsulation. Modulated differential scanning calorimetry (MDSC) and HPLC methods revealed a variety of curcuminoids (curcumin, demethoxycurcumin, bisdemethoxycurcumin, and cyclocurcumin) in the investigated curcumin standard. In addition, the MDSC method was found to be suitable and comparable to HPLC for determining the curcuminoid substances. The analysis of the curcumin release revealed a value of 0.18 w.% after 14 days as the equilibrium value. Furthermore, an increase in the sizes of the emulsions was observed at the end of the 21-day study. The emulsion stability index (ESI) was used to measure the stability of multiple emulsions. The ESI reached 55.8% between 7 and 21 days later. Nano droplets of the oil phase loaded with dispersed curcumin particles captured inside the water-based carboxymethylcellulose micelles were clearly observed by CLSM.

One of the biggest challenges faced by the meat industry is maintaining the freshness of meat while extending its shelf life. Advanced packaging systems and food preservation techniques are highly beneficial in this regard. However, the energy crisis and environmental pollution demand an economically feasible and environmentally sustainable preservation method. Emulsion coatings (ECs) are highly trending in the food packaging industry. Efficiently developed coatings can preserve food, increase nutritional composition, and control antioxidants' release simultaneously. However, their construction has many challenges, especially for meat. Therefore, the following review focuses on the essential aspects of developing ECs for meat. The study begins by classifying emulsions based on composition and particle size, followed by a discussion on the physical properties, such as ingredient separation, rheology, and thermal characteristics. Furthermore, it discusses the lipid and protein oxidation and antimicrobial characteristics of ECs, which are necessary for other aspects to be relevant. Lastly, the review presents the limitations of the literature while discussing the future trends. ECs fabricated with antimicrobial/antioxidant properties present promising results in increasing the shelf life of meat while preserving its sensory aspects. In general, ECs are highly sustainable and effective packaging systems for meat industries.

The aim of this study was to assess the functional properties of butters, spreadable fats, and shortenings, collected from the Czech market, in correlation with their nutritional values declared by the producers. Various methods were applied to determine relevant parameters of the products. Using penetration tests, samples were characterized by specific textural attributes according to their composition and processing type, particularly for the presence of milk/vegetable fats. Using differential scanning calorimetry (DSC), thermal peaks corresponding to medium- and high-melting triacylglycerol fractions were detected in the ranges 15-16 °C and 31.5-34.5 °C, respectively. Rheological analysis revealed that the viscoelasticity of samples was related to frequency behavior of the fat structure, characterized by the dominance of elastic modulus (G') over viscous modulus (G″) up to the frequency of 10 Hz. This indicated good emulsion stability of the products in the region of linear viscoelasticity. For spreadable fats, the structure was resistant to phase separation in the whole frequency range under study (0.1-100 Hz). The results showed that the applied techniques can be successfully used to characterize the processing and compositional quality of butters and vegetable fats.

Polymeric materials play a vital role in our daily life, but the growing concern for the environment demands economical and natural biopolymers that can be cross-linked to create technologically innovative lightweight materials. Their cellular matrix with extreme flexibility makes them highly acceptable for application prospects in material science, engineering, and biomedical applications. Furthermore, their biocompatibility, mechanical properties, and structural diversity provide a gateway to research them to form technologically important materials. In the light of the same, the review covers cellulose derivatives. The first section of the study covers the general properties and applications of cellulose and its derivatives. Then, the biopolymers are characterised based on their dielectric properties, crystallinity, rheology, and mechanical properties. An in-depth analysis of the diffuse process of swelling and dissolution followed by a brief discussion on diffusion and diffusion of crosslinking has been done. The review also covers a section on swelling and swelling kinetics of carboxymethyl cellulose (CMC) and hydroxyethyl cellulose (HEC). The examination of all the aforementioned parameters gives an insight into the future aspects of the biopolymers. Lastly, the study briefly covers some preferred choices of cross-linking agents and their effect on the biopolymers., (Copyright © 2022 Elsevier B.V. All rights reserved.)

This article deals with the characterization of the thermal-induced aging of soft polyurethane (PU) foams. There are studied thermal and mechanical properties by means of thermal analysis, tensile, compression and dynamic mechanical vibration testing. It was found in this study, that the increasing relative humidity of the surrounding atmosphere leads to the initiation of the degradation processes. This is reflected in the observed decreased mechanical stiffness. It is attributed to the plasticization of the PU foams wall material. It is in agreement with the observed increase of the permanent deformation accompanied simultaneously with the decrease of Young's modulus of elasticity. The latter phenomenon is studied by the novel non-destructive forced oscillations vibration-damping testing, which is confirmed by observed lower mechanical stiffness thus indicating the loss of the elasticity induced by samples conditioning. In parallel, observed decreasing of the matrix hardness is confirming the loss of elastic mechanical performance as well. The effect of conditioning leads to the significant loss of the PU foam's thermal stability.

There was studied dough made from refined white and brown wheat flours of different granulometry by means of mechanical, thermal analysis and rheological testing. Observed results were confronted with textural properties of breads. Obtained data confirmed that fine refined white flour dough had high ability to elongate and accumulate stress, in contrary, brown fine flour dough exhibited weaker ability to accumulate stress. Observed increase of the complex viscosity associated with the gelatinization was the fastest in coarse dough, where it gained also the highest peak viscosity. The highest water content liberated was found from fine brown flour bread. This triggered lower water availability for hydration of starch granules in the bread during baking process, thus promoting higher moisture loss affecting thus the overall expansion and porosity of the bread matrix. The latter effect was ascribed to the presence of bran particles in brown flour., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A broader and quantitative understanding of cell adhesion to two-dimensional carbon-based materials is needed to expand the applications of graphene and graphene oxide (GO) in tissue engineering, prosthetics, biosensing, detection of circulating cancer cells, and (photo)thermal therapy. We therefore studied the detachment kinetics of human cancer cells HeLa adhered on graphene, GO, and glass substrates using stagnation point flow on an impinging jet apparatus. HeLa cells detached easily from graphene at a force of 9.4 nN but adhered very strongly to GO. The presence of hydrophilic functional groups thus apparently enhanced the HeLa cells' adherence to the GO surface. On graphene, smaller HeLa cells adhered more strongly and detached later than cells with larger projected areas, but the opposite behavior was observed on GO. These findings reveal GO to be a suitable platform for detecting cells or establishing contacts, e.g. between graphene-based circuits/electrodes and tissues. Our experiments also show that the impinging jet method is a powerful tool for studying cellular detachment mechanisms and adhesion strength, and could therefore be very useful for investigating interactions between cells and graphene-based materials.

Results of inverse gas chromatography adsorption/desorption experiments using selected probes on skimmed milk, whey and demineralised whey powder materials are presented. The dispersive component of surface energy was found to be dominant, indicating a low polarity character. Surface energy profiles of demineralised whey and skimmed milk showed a characteristic steep exponential decrease from approximately 170 mJ/m(2) to 60 mJ/m(2) and 140 mJ/m(2) to 45 mJ/m(2), respectively, whereas whey powder exhibited a constant (non-exponential) surface energy at approximately 45 mJ/m(2). The dispersive surface energy of demineralised whey and skimmed milk powder showed a broad distribution ranging from 40 mJ/m(2) to 120 mJ/m(2) and 175 mJ/m(2), respectively. In contrast, the dispersive surface energy distribution for whey was very narrow, ranging from only 42.8 mJ/m(2) to 45 mJ/m(2). The determined yield locus and Mohr's circles indicated that demineralised whey exhibited free flowing powder characteristics, whereas skimmed milk and whey exhibited cohesive powder flow behaviour., (Copyright © 2014 Elsevier Ltd. All rights reserved.)