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There is an increasing demand for the design of complex bio-composites with customized structural characteristics for use in processed food products. Phase behaviour of these mixtures determines textural properties, encouraging the pursue of a rapid technique that can accurately quantify it. The present work tests the efficacy of confocal laser scanning microscopy (CLSM) coupled with image analysis software (Imaris), for the quantification of phase behaviour in complex tertiary systems. In doing so, it develops phase separated gels of agarose and gelatin supporting inclusions of canola oil. The polysaccharide was replaced with whey protein isolate (WPI) and the topology of the tertiary dispersion with gelatin and canola oil was also examined. Reproducible phase volume estimates were obtained, including those of the lipid phase, which were a close match to the actual concentrations added to the hydrocolloid gel. The approach could offer an alternative to the rheological estimation, via theoretical blending law analysis, of phase volumes in bio-composites. Graphical Abstract

Background Due to the increasing consumer awareness and rapidly changing lifestyle, there has been an exponential increase in the demand for healthy, fresh, minimally processed and Ready-To-Eat food products, especially fresh fruits and vegetables globally. These products though convenient, nutritious, and preferred as healthy alternatives, are also a source of increasing foodborne outbreaks due to their minimal processing marked with insufficient decontamination and preservation. Scope and approach Recent literature was reviewed through search engines and scholarly journals in the areas of food processing and engineering and other related areas. The focus was on the papers published over the last 10 years. Key findings and conclusions The efficacy of cold plasma as a mild, yet effective non thermal technique in inactivating pathogenic microorganisms while maintaining the quality of fresh and minimally processed fruits and vegetables and extending their shelf life is summarized and reviewed. Cold plasma is capable of producing safe fresh fruits and vegetables. The efficiency of the technique depends on product surface properties and several processing parameters that needs be optimized to achieve desirable results. Further research is needed to fine tune and streamline cold plasma processing in order to have a widespread industrial application for safe fresh and minimally processed fruits and Ready-To-Eat vegetables. Future research would focus on expanding industrial applications of cold plasma technology through product safety as well as designing and modeling universal plasma application systems capable of processing different fruits and vegetables without requiring time consuming set up trials.

Background Food colloid stability is critical to many food properties and surfactants that can provide long-term stability against phase separation are highly desirable. The hydrophobins and the chaplins are proteins secreted by filamentous microorganisms that spontaneously self-assemble into amphipathic layers at a hydrophilic-hydrophobic interface providing surface activity. These proteins have great potential as biosurfactants or foaming agents in food products and other dispersed systems. Scope and approach This review seeks to provide a better understanding of the common structural features of the hydrophobin and chaplin proteins and their functional properties, including surface activity, which arise from these structural features. The ability of these two protein classes to assemble at the interface and stabilize dispersed systems is compared. The mechanism of protein self-assembly at the interface, role of cysteine residues in self-assembly and the formation of fibrils are also explored. Potential methods and challenges in the production of these proteins for commercial applications are reviewed, together with new promising areas of research. Key findings and conclusions The hydrophobins and chaplins display a surface activity comparable to traditional surfactants and form interfacial films with highly favourable rheological properties. Proteins from these two groups of naturally derived molecules have the potential to stabilize food or pharmaceutical dispersions against coalescence and disproportionation over a wide range of pH for lengthy periods of time (up to 45 days). While there is a significant promise for their use in the stabilization of dispersed systems, further optimization of protein production yield will be required for commercial applications.

Previous work has suggested the ability of 4-hydroxybenzoic acid (4HBA) to bind to β -casein following ultra high temperature-like processing (UHT) in model aqueous systems. The present work confirmed directly, using MALDI-TOF-MS, the presence of covalently bound 4HBA following UHT-like treatment. In subsequent molecular dynamics simulations, the 3D structure of the β -casein molecule was modified so that the meta-C of 4HBA ring and the side chain amino group of lys32 were linked covalently. Such simulations further indicated that the covalent addition of the phenolic compound had impacted the protein density and solvent accessibility. Hydrogen bond analysis between lys32 and the remainder of the protein structure revealed that the covalent complexation supported the formation of additional hydrogen bonds. These increased from potentially 9, in the single protein molecule, to 51 in the complex with 4HBA. However, the persistence of hydrogen bonds was reduced, leading overall to decreased stability and increased protein flexibility.

The need for a rapid and direct alternative to the rheology-based blending laws in quantifying phase behaviour in biopolymer composite gels is explored in this study. In doing so, the efficacy of confocal laser scanning microscopy (CLSM) paired with image analysis software – FIJI and Imaris - in quantifying phase volume was studied. That was carried out in a model system of agarose with varying concentrations of microcrystalline cellulose (MCC) in comparison to the rheological blending laws. Structural studies performed using SEM, FTIR, differential scanning calorimetry and dynamic oscillation in-shear unveiled a continuous, weak agarose network supporting the hard, rod-shaped MCC inclusions where the composite gel strength increased with higher ‘filler’ concentration. The phase volumes of MCC, estimated with the microscopic protocol, matched the predictions obtained from computerized modelling using the Lewis-Nielsen blending laws. Results highlight the suitability of the microscopic protocol in estimating the water partition and effective phase volumes in the agarose-MCC composite gel.

The Chaplin E peptide is a surface-active agent that can adsorb to the air/water interface and form interfacial films that display distinct interfacial properties as a function of pH. The ~2 nm thick homogeneous Chaplin E film formed under acidic conditions contains ordered structures that give a high dilatational elasticity. In contrast, the heterogeneous film formed under basic conditions contained fibrils resulting in a rough ~17 nm thick film with predominantly viscoelastic properties, probably due to the reduced intermolecular interactions. These fibrils were also susceptible to breakage, fragmenting into shorter fibrils, which gave a greater elasticity. The fibrils also lead to a greater shear viscosity compared to the ordered structures aligned within the Chaplin E film at pH 3.0. A higher stability was observed for the foam formed by the Chaplin E compared to the foam formed by β-lactoglobulin, consistent with the greater rheological properties observed for the Chaplin E film at the interface. Our findings suggest that Chaplin E has potential to provide long time stability to dispersions in food, consumer goods or pharmaceutical applications, forming films with greater rheological properties and at least similar thickness to those formed by other surface-active proteins such as β-casein and β-lactoglobulin.

A novel approach for distinguishing the viscoelastic and thixotropic phenomena of predisturbed and intact networks at short and long timescales of observation was proposed using stress relaxation, creep/recovery, single shear decay, and in-shear structural recovery experiments. The method was able to illustrate the connections patterns of the internal microstructure of hydrocolloids and its alteration over time. To test the universality of the new approach, we studied seven commercial and four emerging hydrocolloids. Moreover, to find out the correlation between the proposed parameters from this approach and the fundamental rheological parameters of the selected hydrocolloids, a principal component analysis (PCA) was employed, which showed an excellent correlation between the parameters of all hydrocolloids in predisturbed and intact states at short and long timescales. This work assumed that two different patterns of linkage connection exist, but the analysis can be extended to more than two connection patterns of linkages.

Gelatinization, pasting, digestibility and estimated glycaemic index of six high amylose rice varieties differing in length/width ratio were studied. Amylose content ranged narrowly (27.8–29.1%). Resistant starch content ranged from 0.44% to 1.4%. In contrast to gelatinisation enthalpy, gelatinisation temperature (GT) ranged narrowly (76.7–77.4 °C). For all rice varieties, melting temperature of amylose‐lipid complex I and II was around 99 °C and 110 °C, respectively. The enthalpy of amylose‐lipid complex I and II ranged between 0.18–0.87 and 0.23–0.55, respectively. Expected in vitro glycaemic index (GI) of all tested varieties was similar (88.2–92.4). The results showed that the size of the rice grain (length/width) and resistant starch content had no apparent impact on the GI of high amylose rice. The dominant factors determining the digestibility and glycaemic response of the tested high amylose rice varieties seemed to be amylose content and the GT. Besides the pasting temperature, other pasting properties varied significantly but were not correlated to starch digestibility and estimated GI among the six rice varieties. Thus, RVA pasting properties, except for pasting temperature, may not be good predictors for the GI of these high amylose rice.

Dynamic rheological and mechanical properties of seven commercial (xanthan [XG], guar [GG], high methoxylated pectin [HMP], κ-carrageenan [κ-Car], agar [AG], alginate [ALG], and carboxymethylcellulose [CMC]) and four emerging hydrocolloids (basil seed gum [BSG], sage seed gum [SSG], Balangu-Shirazi seed gum [BSSG], and cress seed gum [CSG]) were investigated and the classification of the hydrocolloids were carried out based on them. AG belonged to the first class with 0.81 membership function (MF), κ-Car and HMP grouped in the second class with 0.68 and 0.71 MFs, respectively, XG, BSG, and SSG were depended to the third class with 0.61-0.70 MFs, finally, CMC, GG, BSSG, ALG, and CSG related to the fourth class, as the most populated class, with MF > 0.61. The first class contained the highest amount of hardness parameter (43.40 ± 2.76 g), the second class included the highest pseudoplasticity parameter (shear-thinning ratio = -0.54 ± 0.03) and relaxation time (66.25 ± 2.61 s) and the fourth cluster comprised the highest frequency dependency of viscous modulus (exponent of power-law model for viscous modulus vs. frequency = 0.30 ± 0.05). In addition, the results of this study showed that there was a distinct relationship between nonlinear harmonics in the stress wave and fundamental characteristics of hydrogel networks. The investigation of the rheo-mechanical properties of biopolymers in large deformation under shear and normal forces can have an important role in the prediction of the behavior of the material in real processes and application conditions, especially in the food industry. Due to the inconvenience of large deformation mechanical tests, such as Weissenberg effect, the complication of the results analyzing and sampling difficulty of semi-dilute samples; herein, we determined the correlation between large deformation (LAOS and texture analysis) and small deformation (SAOS) tests properties. The studied rheo-mechanical parameters showed high correlation with the four mentioned network parameters (more than 65% similarity index). Using these results, other scientists could rationally design the experiments and avoid experiments with similar parameters.

Honey is a biologically active material functioning antibacterial, anti-inflammation and immune responses that enhance wellbeing. This research aims to record and rationalise the structural properties of honey as part of a convenient delivery system in the presence of gelatin that provides the structuring matrix. In doing so, we employ dynamic oscillation in-shear, micro and modulated DSC, WAXD, FTIR and ESEM. A wide range of solids was employed from 10% (w/w) gelatin to mixtures with up to 75% (w/w) honey. Increasing addition of co-solute created thermally stable gelatin networks, which at high levels of total solids undergo a glass transition. This allows deconvolution of the total heat flow into the reversing and non-reversing thermograms. In addition, mechanical spectra can be treated by the combined free volume/reaction rate theory to predict the molecular dynamics of the gelatin-honey system. Molecular interactions between the two components and the relative contribution of honey to the crystalline or amorphous part of the binary preparation are elucidated guiding future applications for orally and topically treated ailments.

Optimal protein performance in techno-functional and bio-functional foods is largely determined by thermal processing, leading to physical or chemical interactions with other constituents found in the commercial formulation. There is a need to understand at a fundamental level the kinetics of molecular transport of bioactive compounds, including vitamins, essential fatty acids, antioxidants and caffeine, from protein-based excipients in nutraceutical-type products. Physical interactions in these systems are further manipulated by crosslinking the protein network for controlled delivery in relation to the physicochemical environment of the release medium. Altering the processing conditions from ambient and pasteurisation temperatures to UHT treatment brings into play the denaturation of the milk protein, added to beverages that affects its association with phenolic compounds. These are found naturally in oat or wheat insoluble fibre, which is increasingly incorporated in formulations of added value foods, for example liquid breakfast. Potential formation of chemical interactions between hydroxycinnamic or hydroxybenzoic acids from insoluble dietary fibre and milk proteins following UHT processing and prolonged storage at ambient temperature may involve unexpected physiological and nutritional effects. We aim to review the significant results in this new and evolving field of dairy protein–ligand interactions in an effort to assist with planning further experiments for the design of convenient and nutritious foods.

Temperature induced interactions between β-casein and ferulic acid were investigated under ultra-high temperature (UHT) conditions (140 °C) utilising a variety of spectroscopic methods. Fluorescence measurements indicate that structural alterations to the protein have occurred; the resulting red shift in tryptophan peak fluorescence with increasing concentrations of ferulic acid indicates that the single tryptophan residue has become more exposed to the polar environment. This evidence is further supported by Fourier transform infrared (FTIR) and circular dichroism (CD) measurements showing an increase in irregular and intermediary structural components upon addition of ferulic acid, as well as UV-vis measurements that record an increase in absorption. High performance liquid chromatography (HPLC) work strongly argues that the ferulic acid is bound covalently to the protein post heat treatment. This outcome is in agreement with molecular docking simulations and quantum mechanics calculations that indicate the formation of a covalent bond between ferulic acid and glutamine54 residue of β-casein to create a new adduct.

The purpose of this research is to investigate swellable genipin-crosslinked gelatin matrices for the controlled delivery of water soluble vitamins (ascorbic acid). The following methods were utilized to describe the physicochemical properties of the system: micro differential scanning calorimetry and small deformation dynamic oscillation in shear. Hydrogel microstructural properties were reported in terms of the average molecular weight between crosslinks and network mesh size. Degree of crosslinking in gels with concentration of genipin crosslinker from 0 to 2.8% (w/w) was measured using ninhydrin assay and UV-vis spectroscopy. Swelling of the gel matrix in aqueous solvent was followed and colorimetric methods were used to measure the diffusion kinetics of ascorbic acid from the gel to the surrounding aqueous phase. Results after treatment of swelling data with improved Fickian theory found matrix swelling was limited by the relaxation of polymer chains. Significance of results lies in the derivation of apparent diffusion coefficients for the transport of water molecules and bioactive compound at 85% and 98% crosslinking that relates the kinetics of bioactive compound release to mesh size of the polymeric network. Thus, there is strong evidence that modulation of the extent of crosslinking impacts on hydrogel morphological characteristics and structural properties, with resulting control of bioactive compound release. Outcomes may be implemented in targeted delivery of bioactive compounds, including vitamins, within the human body, for improved bioavailability.

Delivery of techno- and bio-functionality in all-natural processed foods is an area of steadily increasing fundamental and technological interest. One of the main aspects in this field is based on the diffusion of natural bioactive compounds that have been incorporated in high-solid biopolymers matrices. Organoleptic considerations dictate that the delivery vehicles are characterised by a highly amorphous fraction in the biopolymer network. Molecular diffusion in the amorphous state is a complex process associated with the effect of the glass transition temperature (Tg) on the mobility of low molecular-weight bioactives. This work will review the molecular dynamics of high-solid biopolymer systems, and model food preparations in the presence of co-solute, in relation to the diffusion kinetics of natural bioactive compounds. Literature indicates that the metastable properties of condensed biopolymer networks traversing the rubber-to-glass transition region affect significantly the diffusion kinetics of bioactive compounds. These have been modelled using concepts from the classical and improved diffusion theory to unveil a relationship between apparent diffusion coefficient of bioactives and free volume characteristics of the condensed biopolymer network. Further work is required in added value foods, sourcing inspiration from the “sophisticated pharmaceutical research”, to develop food systems that control transport phenomena for targeted release from a specific dosage form.

A fundamental study was carried out to evaluate patterns of vitamin B6 release from genipin crosslinked gelatin in aqueous media at ambient temperature. Up to ninety percent crosslinking was achieved, with FTIR and WAXD data arguing for partial replacement of the triple helix with a covalent pattern of bonding between protein and crosslinker. Formation of a “composite network” yielded increasing compressive stress-at-failure values followed by a decrease as a function of genipin addition, with the yield strain decreasing continuously. Electron microscopy images showed a reduction in the size of the hydrogel pores with a higher degree of crosslinking. Experimental evidence was supported by the Flory-Rehner theory that predicted a lower swelling ratio and reduced molecular weight between adjacent crosslinks with genipin addition. Furthermore, Peppas-Sahlin equation was used to rationalise the interplay between network morphology and diffusion of bioactive compound over prolonged timeframes of release testing.

There is a growing need for clean and green labeling of food products among consumers globally. Therefore, development of green modified starches, to boost functionality, palatability and health benefits while reducing the negative processing impacts on the environment and reinforcing consumer safety is in high demand. Starch modification started in mid-1500s due to the inherent limitations of native starch restricting its commercial applications, with chemical modification being most common. However, with the recent push for "chemical-free" labeling, methods of physical and enzymatic modification have gained immense popularity. These methods have been successfully used in numerous studies to alter the composition, structure, functionality and digestibility of starch and in this review, studies reported on green modification of cassava starch, one of the most common utilized starches, within the last ten years have been critically reviewed. Recent research has introduced starch as an abundant, natural substrate for producing resistant starches through biophysical technologies that act as dietary fiber in the human body. It is evident that different techniques and processing parameters result in varying degrees of modification impacting the techno-functionality and digestibility of the resultant starch. This can be exploited by researchers and industrialists in order to customize starch functionality in accordance with application.

Crosslinking of hydroxypropyl methyl cellulose (HPMC) and acrylic acid (AAc) was carried out at various compositions to develop a high-solid matrix with variable glass transition properties. The matrix was synthesized by the copolymerisation of two monomers, AAc and N,N′-methylenebisacrylamide (MBA) and their grafting onto HMPC. Potassium persulfate (K2S2O8) was used to initiate the free radical polymerization reaction and tetramethylethylenediamine (TEMED) to accelerate radical polymerisation. Structural properties of the network were investigated with Fourier transform infrared spectroscopy (FTIR), Xray diffraction (XRD), modulated differential scanning calorimetry (MDSC), small-deformation dynamic oscillation in-shear, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The results show the formation of a cohesive macromolecular entity that is highly amorphous. There is a considerable manipulation of the rheological and calorimetric glass transition temperatures as a function of the amount of added acrylic acid, which is followed upon heating by an extensive rubbery plateau. Complementary TGA work demonstrates that the initial composition of all the HPMC-AAc networks is maintained up to 200 °C, an outcome that bodes well for applications of targeted bioactive compound delivery.

Manuka honey and newly developed honeys (arjuna, guggul, jiaogulan and olive) were examined for their physicochemical, biochemical properties and effects on oxidative stress and cholesterol homeostasis in fatty acid-induced HepG2 cells. The honeys exhibited standard moisture content (&lt, 20%), electrical conductivity (&lt, 0.8 mS/cm), acidic pH, and monosaccharides (&gt, 60%), except olive honey (&lt, 60% total monosaccharides). They all expressed non-Newtonian behavior and 05 typical regions of the FTIR spectra as those of natural ones. Guggul and arjuna, manuka honeys showed the highest phenolic contents, correlating with their significant antioxidant activities. Arjuna, guggul and manuka honeys demonstrated the agreement of total cholesterol reduction and the transcriptional levels of AMPK, SREBP2, HCMGR, LDLR, LXR&alpha, Jiaogulan honey showed the least antioxidant content and activity, but it was the most cytotoxic. Both jiaogulan and olive honeys modulated the tested gene in the pattern that should lead to a lower TC content, but this reduction did not occur after 24 h. All 2% concentrations of tested honeys elicited a clearer effect on NQO1 gene expression. In conclusion, the new honeys complied with international norms for natural honeys and we provide partial evidence for the protective effects of manuka, arjuna and guggul honeys amongst the tested ones on key biomarkers of oxidative stress and cholesterol homeostasis, pending further studies to better understand their modes of action.

Interactions between the dimeric form of β-lactoglobulin and vanillic acid were investigated at pH 7.2, using a variety of spectroscopic techniques and molecular dynamics (MD) simulations. FTIR and CD studies showed alterations in the secondary structure of the protein upon its interaction with the ligand. Fluorescence measurements indicated that the dimeric complex with the phenolic acid produced a large dissociation constant (K

High-solid chitosan matrices were prepared to investigate the effect of their swelling on structural relaxation and glass transition. Degree of crosslinking in genipin-crosslinked chitosan networks was measured with a ninhydrin assay and a suitable crosslinker concentration was determined for gels used in swelling and thermomechanical analysis. Fourier transform infrared spectroscopy and wide angle X-ray diffraction examined the intermolecular interactions, crystallinity and amorphicity of the biopolymer networks. Swelling characteristics following immersion in water included approximate equilibrium values of the average molecular weight between crosslinks and network mesh size, e.g. 902 g mol−1 and 110 nm for the preparation with an initial solids content of 60% (w/w) after 80 min of swelling, which were quantified with the modified Flory-Rehner theory. Thermal glass transition temperature was observed in the condensed crosslinked networks (≥ 70% w/w total solids) during differential scanning calorimetry experiments. Time-temperature superposition of rheological measurements, obtained with dynamic oscillation in-shear, generated a master curve describing the viscoelastic behaviour of the system, moving through the rubbery, glass transition region and glassy state. Combined analysis using the modified Arrhenius and William-Landel-Ferry theories determined mechanical glass transition temperatures in the range of −68 to −8 °C for the crosslinked biopolymer at intermediate-solid concentrations (40 to 60% w/w solids). An understanding of the effect of swelling on molecular network characteristics was achieved, which is crucial for greater control in the design of systems for the targeted delivery of bioactive compounds.

The impacts of sonication on functional properties of lupin protein isolates derived from lupin flour was investigated. The lupin protein isolates of pH 5 and 9 were then treated with low-frequency ultrasound throughout an energy density range of 457–2746 J/mL. The physicochemical and functional properties including particle size, solubility, zeta potential, rheological, thermal properties and molecular weight of the samples were measured. Ultrasound treatment was effective in reducing the particle size of the lupin protein isolates for the pH 5 sample to less than 10 μm, and less than 1 μm for the pH 9 suspension. Ultrasound also increased the solubility of lupin protein across the pH profile. Zeta potential wasn't affected to any significant extent, as it remained unchanged at −5 for the pH 5 protein isolate, and −27 mV for the pH 9 protein sample after ultrasound treatment. Following sonication, the viscosity of the pH 5 lupin protein increased, where the highest viscosity measurement of 1000 mPa s being achieved for the sample sonicated at an energy density of 1830 J/mL; in contrast, viscosity decreased with higher energy densities for the pH 9 sample. The storage modulus behaviour demonstrated the efficacy of ultrasound for improving the gelling properties of the lupin protein samples at pH 5, with 4000Pa being measured upon sonication at an energy density of 2746 J/mL; on contrast, the pH 9 sample possessed poor gelling properties despite ultrasound treatment. Finally, the DSC curves indicated an inverse correlation between the energy density of ultrasound treatment and enthalpy.

There is a substantial volume of research articles in the field of protein-ligand interactions, with a large proportion using inappropriate methodology for the fluorescence spectroscopy analysis of binding interactions. The most common issues being overlooked are the inner filter effect and the use of unsuitable equations to calculate binding strength and stoichiometry, leading to the propagation of questionable methodology and reported results throughout multiple fields. In this communication, we carefully explain these issues and approaches to overcome them, including accounting for the inner filter effect, the use of appropriate equations to obtain dissociation constant (Kd) values (as opposed to the commonly misused Stern-Volmer equation), and carefully dealing with binding stoichiometry using the Job plot (often misjudged using the Hill coefficient instead). We hope that the work will bring attention to critical and often common issues in fluorescence spectroscopy, as well as improving the approaches used in the binding analysis of protein-ligand systems. Thus, it should provide a good example of how to go about this type of research, as well as being of interest to the broad readership of the journal.

Vitamin entrapment in matrices made of natural polymers and its controlled release has application to a variety of added value foods and nutraceuticals. This communication utilises data from published literature on the molecular transport of vitamin B6 from condensed matrices of genipin-crosslinked gelatin, bovine serum albumin and whey protein isolate to develop a mechanistic model that accounts for moving boundary conditions. In doing so, it utilises the apparent diffusion coefficient of the micronutrient, the molecular weight of the uncrosslinked polymer chain and the average molecular weight between neighbouring crosslinks. The derived mathematical expression for swellable matrices in an aqueous environment can follow the progression of diffusivity with degree of crosslinking in the polymeric excipients. Model fitting provides a minimisation parameter, which is interpreted in terms of the extent of coupling between solute diffusion and matrix structural relaxation. Parallel predictions of polymer network mesh and critical molecular weight between crosslinks indicate that values of normalised size well above one are required for anomalous (non-Fickian) release due to obstructed diffusion.

Changes in the structural properties of hydrogels made with gelatin and bovine serum albumin mixtures were recorded following exposure to high pressure at 300 MPa for 15 min at 10 and 80 °C. Dynamic oscillation, SEM, FTIR and blending law modelling were utilised to rationalise results. Pressurization at the low temperature end yielded continuous gelatin networks supporting discontinuous BSA inclusions, whereas an inverted dispersion was formed at the high temperature end with the continuous BSA network suspending the discontinuous gelatin inclusions. Lewis and Nielsen equations followed the mechanical properties of the composites thus arguing that solvent partition between the two phases was always in favour of the polymer forming the continuous network. As far as we are aware, this is the first attempt to elucidate the solvent partition in pressurised hydrogel composites using blending law theory. Outcomes were contrasted with earlier work where binary mixtures were subjected only to thermal treatment.

In this study, we proposed an objective classification of seven commercial hydrocolloids and four novel hydrocolloids. Total of 74 rheological parameters was generated by steady (flow behavior, hysteresis loop, single shear decay, in-shear structural recovery experiments), dynamic (strain sweep and frequency sweep tests), and transient (creep/recovery and stress relaxation) shear measurements. Subsequently, the parameters were classified into seven categories with more than 60% similarity indexes in each group using agglomerative hierarchical clustering based on those properties related to the number of linkage, strength of linkage, distance of linkage, rupture and flow, rate of destruction, the extent of destruction, and the state of destructured samples in the absence of flow field. Fuzzy c-means classifier used to extract patterns for each class. Our results correspond to four different classes; κ-carrageenan and agar gum were categorized in the first class, high methoxyl pectin, xanthan, sage seed gum and basil seed gum in the second class, alginate gum and Balangu-Shirazi seed gum in the third class, and guar gum, cress seed gum and carboxymethyl cellulose in the fourth class. Using this classification technique, complete rheological patterns can be extracted for each class. This classification provides a map for other researchers to rationally design the best test type which could describe adequately different properties of materials and avoid experiments with a similar type of parameters. The main reason for the frequent use of hydrocolloids in various industries is their ability to modify the rheology. A lot of works have been done to study the rheological behavior of many hydrocolloids in model and food systems. As there is still demand for new sources of hydrocolloids with more specific functionality in foods, probing the similarities among commercial and emerging hydrocolloids could help us to rationally design structural features in different formulations, besides gives insight into the structure-function relationship between them. This object could be attained by clustering, a part of the pattern recognition theory. Contrary to the traditional clustering methods, in which the membership of a product is exclusive for only a class, in constraint clustering by fuzzy logic methods, a partial membership can be shared by two or more classes. In this way, using the fuzzy logic clustering method, we clustered a number of commercial and novel hydrocolloids based on the steady, transient, and dynamic shear rheological properties and found a specific pattern among them. PRACTICAL APPLICATIONS: The main reason for the frequent use of hydrocolloids in various industries is their ability to modify the rheology. A lot of works have been done to study the rheological behavior of many hydrocolloids in model and food systems. As there is still demand for new sources of hydrocolloids with more specific functionality in foods, probing the similarities among commercial and emerging hydrocolloids could help us to rationally design structural features in different formulations, besides gives insight into the structure-function relationship between them. This object could be attained by clustering, a part of the pattern recognition theory. Contrary to the traditional clustering methods, in which the membership of a product is exclusive for only a class, in constraint clustering by fuzzy logic methods, a partial membership can be shared by two or more classes. In this way, using the fuzzy logic clustering method, we clustered a number of commercial and novel hydrocolloids based on the steady, transient, and dynamic shear rheological properties and found a specific pattern among them.

Functionalized halloysite nanotubes were prepared by surface activation of halloysite (Hal) with sodium hydroxide and deposition of zinc oxide nanoparticles (ZnONP). The surface charge of Hal was changed from 0.18 ± 0.6 mV to −35.2 ± 2.8 mV after alkali treatment. The functionalized Hal (AT-Hal/ZnONP) was incorporated into alginate biopolymer as a reinforcing filler with different concentration of AT-Hal/ZnONP (1, 3, 5, and 7 wt% of alginate). Alginate films with AT-Hal/ZnONP exhibited a significant increase in the mechanical, water vapor barrier, and UV light barrier properties. The thermal stability of composite films has not changed after AT-Hal/ZnONP incorporation. The AT-Hal/ZnONP incorporated alginate films demonstrated strong antibacterial activity against food-borne pathogenic bacteria, Escherichia coli and Listeria monocytogenes. The nanocomposite film with 7 wt% of AT-Hal/ZnONP exhibited complete sterilization of E. coli and L. monocytogenes after 3 and 9 h of treatment, respectively.

The present study examines the influence of ultra high temperature (UHT) treatment and storage conditions (22 and 40 °C) on the phenolic acid and avenanthramide composition of oat samples during 12-week shelf life. The evolution of free fatty acid and volatile compounds is also investigated due to their impact on storage quality. Ferulic acid is found as the most abundant phenolic acid in oat samples followed by p-coumaric acid. Chromatographic analysis also detects the presence of major avenanthramides (A, B and C), free fatty acids (palmitic, oleic and linoleic acids), and volatiles (hexanal and 2-pentyl furan) in our materials. Following UHT treatment, total phenolic content (TPC), phenolic acids, avenanthramides and free fatty acids were reduced. However, prolonged storage of the UHT-treated preparations at ambient temperature has a positive effect on the content of TPC, phenolic acids, avenanthramides, free fatty acids and volatile compounds. In contrast, extended storage at a higher temperature (40 °C) leads to a decrease in the TPC and phenolic acid content, with the levels of avenanthramides and volatiles increasing with time. Overall, UHT treatment and storage conditions have a considerable effect on the composition of bioactive compounds in oat samples of industrial interest.

We obtained extracts from beet greens using conventional and ultrasound treatments. The work focused on betacyanins, betaxanthins and polyphenols from the extracts following the two distinct extraction protocols. These were used as the bioactive compounds in alginate capsules in order to follow patterns of controlled delivery in simulated gastrointestinal fluids. FTIR was performed to show the nature of interactions between excipient and bioactives. Swelling behaviour and mechanical characterization of the polysaccharide network showed that it remains firm in the harsh gastric conditions but exhibits soft consistency in the simulated environment of the small intestine. There is a direct relationship between mechanical characteristics, hence swelling of the beads, and release rates of bioactives within the in-vitro environment. Peppas-Sahlin equation was applied successfully to demonstrate that the relaxation contribution dominates with increasing time of observation, an outcome that confirms the role of swelling of the alginate capsules in bioactive compound release.