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Food science‐based graduates are a significant proportion of the United Kingdom (UK) food and drink industry's workforce. Aside from technical standards, there is no cohesive competency framework to support key stakeholders; employers, students, and degree providers. Clarity of desirable competencies for the range of graduate opportunities available would enable students to undertake effective career planning and personal development, and educators to refine programs to satisfy market needs. Using a previously developed language tool, a Likert style, industry‐wide online survey in UK and Republic of Ireland (ROI) was conducted involving 218 participants from a broad range of food science‐related employment areas, evaluated by a combination of descriptive and multivariate data analysis. The survey outcomes indicate types of desirable competencies in a food science graduate. The tailored competency framework, Competencies for Food Graduate Careers (CFGC), is a set of 48 elements across eight themes, outlining which are desirable for each of 14 typical initial graduate roles. To enhance the quality of “oven‐ready” graduates entering the food industry, it is recommended CFGC be used for careers education and competency development in higher education. The framework is aimed to have further applications for job specification development and also to improve awareness of careers in the food industry.

Staphylococcus aureus is the cause of a spectrum of diseases in humans and animals. The molecular basis of this pathogenicity lies in the expression of a variety of virulence factors, including proteins that mediate adherence to the host plasma and extracellular matrix proteins. In this study, we discovered that the iron-regulated surface determinant B (IsdB) protein, besides being involved in iron transport and vitronectin binding, interacts with von Willebrand Factor (vWF). IsdB-expressing bacteria bound to both soluble and immobilized vWF. The binding of recombinant IsdB to vWF was blocked by heparin and reduced at high ionic strength. Furthermore, treatment with ristocetin, an allosteric agent that promotes the exposure of the A1 domain of vWF, potentiates the binding of IsdB to vWF. Both near-iron transporter motifs NEAT1 and NEAT2 of IsdB individually bound recombinant A1 domain with KD values in the micromolar range. The binding of IsdB and adhesion of S. aureus expressing IsdB to monolayers of activated endothelial cells was significantly inhibited by a monoclonal antibody against the A1 domain and by IsdB reactive IgG from patients with staphylococcal endocarditis. This suggests the importance of IsdB in adherence of S. aureus to the endothelium colonization and as potential therapeutic target.

Two strategies were combined and applied in this study to achieve a desired structure and texture of gluten free crackers and to reduce the calorie content. The first strategy is increasing structural heterogeneity of crackers and doughs and a separated-dough method was developed. A butter dough and a water dough were prepared separately and mixed together and the influence of mixing time was investigated. In the second strategy, which is the incorporation of a structuring material, powdered cellulose and fibrillated cellulose were incorporated in formulation to replace flour and pregelatinised starch with enhanced health benefits of low calorie and high fibre. Powdered cellulose played the role of the skeleton of the gluten free crackers. A laminar structure was observed in crackers when powdered cellulose was initially added to the butter dough. The crackers exhibit high thickness, hardness and fracturability and sharp sound emission which are typically observed in wheat crackers. Pregelatinised starch can be replaced by fibrillated cellulose at a lower addition level.

The production of gluten free crackers is challenging because the formation of a gluten network is required. This study investigated the effects of psyllium seed husk powder (PSY), methylcellulose (MC), pregelatinised starch (PGS), and cold water swelling starch (CWSS) on gluten free crackers made of rice flour. The evaluations of pasting properties, dough rheological properties, textural properties, acoustic emissions, and structures were included in this study. Gluten free cracker doughs were more solid-like compared to wheat doughs based on their frequency dependence shown in the mechanical spectra. However, PGS significantly increased the fluid-like property and shapeability. The addition of MC at a high level significantly modified the pasting profile and a secondary swelling and breakdown might occur. As for the crackers, PSY and PGS crackers had comparable textural properties and sound release to wheat crackers, while CWSS crackers were slightly weaker. However, MC did not improve the textural properties compared to rice crackers because the interaction between the MC molecules was limited at the low water addition level, which limited its functionality in cracker making.

Staphylococcus aureus is a Gram-positive bacterium that can cause both superficial and deep-seated infections. Histones released by neutrophils kill bacteria by binding to the bacterial cell surface and causing membrane damage. We postulated that cell wall-anchored proteins protect S. aureus from the bactericidal effects of histones by binding to and sequestering histones away from the cell envelope. Here, we focused on S. aureus strain LAC and by using an array of biochemical assays, including surface plasmon resonance and ELISA, discovered that fibronectin-binding protein B (FnBPB) is the main histone receptor. FnBPB bound all types of histones, but histone H3 displayed the highest affinity and bactericidal activity and was therefore investigated further. H3 bound specifically to the A domain of recombinant FnBPB with a KD of 86 nm, ∼20-fold lower than that for fibrinogen. Binding apparently occurred by the same mechanism by which FnBPB binds to fibrinogen, because FnBPB variants defective in fibrinogen binding also did not bind H3. An FnBPB-deletion mutant of S. aureus LAC bound less H3 and was more susceptible to its bactericidal activity and to neutrophil extracellular traps, whereas an FnBPB-overexpressing mutant bound more H3 and was more resistant than the WT. FnBPB bound simultaneously to H3 and plasminogen, which after activation by tissue plasminogen activator cleaved the bound histone. We conclude that FnBPB provides a dual immune-evasion function that captures histones and prevents them from reaching the bacterial membrane and simultaneously binds plasminogen, thereby promoting its conversion to plasmin to destroy the bound histone.

Staphylococcus lugdunensis is a species of coagulase-negative staphylococcus (CoNS) that causes serious infections in humans akin to those of S. aureus. It was often misidentified as S. aureus, but this has been rectified by recent routine use of matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) in diagnostic laboratories. It encodes a diverse array of virulence factors for adhesion, cytotoxicity, and innate immune evasion, but these are less diverse than those encoded by S. aureus. It expresses an iron-regulated surface determinant (Isd) system combined with a novel energy-coupling factor (ECF) mechanism for extracting heme from hemoproteins. Small cytolytic S. lugdunensis synergistic hemolysins (SLUSH), peptides related to phenol-soluble modulins of S. aureus, act synergistically with β-toxin to lyse erythrocytes. S. lugdunensis expresses a novel peptide antibiotic, lugdunin, that can influence the nasal and skin microbiota. Endovascular infections are initiated by bacterial adherence to fibrinogen promoted by a homologue of Staphylococcus aureus clumping factor A and to von Willebrand factor on damaged endothelium by an uncharacterized mechanism. S. lugdunensis survives within mature phagolysosomes of macrophages without growing and is released only following apoptosis. This differs fundamentally from S. aureus, which actively grows and expresses bicomponent leukotoxins that cause membrane damage and could contribute to survival in the infected host. S. lugdunensis is being investigated as a probiotic to eradicate S. aureus from the nares of carriers. However, this is contraindicated by its innate virulence. Studies to obtain a deeper understanding of S. lugdunensis colonization, virulence, and microbiome interactions are therefore warranted.

The bacterium Listeria monocytogenes is a serious concern to food processing facilities because of its persistence. When liquid cultures of L. monocytogenes were prepared in defined media, it was noted that planktonic cells rapidly dropped out of suspension. Zeta potential and hydrophobicity assays found that the cells were more negatively charged (−22, −18, −10 mV in defined media D10, MCDB 202 and brain heart infusion [BHI] media, respectively) and were also more hydrophobic. A SEM analysis detected a capsular-like structure on the surface of cells grown in D10 media. A crude extract of the extracellular polymeric substance (EPS) was found to contain cell-associated proteins. The proteins were removed with pronase treatment. The remaining non-proteinaceous component was not stained by Coomassie blue dye and a further chemical analysis of the EPS did not detect significant amounts of sugars, DNA, polyglutamic acid or any other specific amino acid. When the purified EPS was subjected to attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, the spectra obtained did not match the profile of any of the 12 reference compounds used. An x-ray diffraction (XRD) analysis showed that the EPS was amorphous and a nuclear magnetic resonance (NMR) analysis detected the presence of glycerol. An elemental energy dispersive x-ray (EDX) analysis showed traces of phosphorous as a major component. In conclusion, it is proposed that the non-proteinaceous component may be phospholipid in nature, possibly derived from the cell wall lipoteichoic acid.

Plant breeders are focused on creating new varieties of wheat with enhanced yield potential without affecting the quality of wheat for food. In this study, four cultivated varieties of wheat, Triticium asetivum and two wild relatives of wheat; Triticum timopheevii and Triticum urartu were studied. The impact of starch and protein content on structural, thermal and water sorption properties of four main wheat cultivars in comparison to the wild relatives has been studied. Wild relatives of wheat required higher temperatures to initiate starch gelatinisation and amylose/lipid complex formation as compared to the four main wheat cultivars. The carbohydrate region in FTIR indicates structural differences (ordered and unordered starch) in the different varieties of wheat flour. The differentiation between wild relatives and main varieties is at the species level. Both wild relatives showed a noticeable difference in moisture sorption behaviour as compared with the 4 main cultivars, especially in terms of monolayer (M0) and the strength of water binding to the primary sites (C) values.

[EN] Fruits are essential components of a healthy diet contributing to the prevention of different diseases. Nevertheless, their consumption is limited among the population for reasons of convenience, among others. High-quality products are obtained by freeze-drying; however, dehydrated fruit presents a physical stability problem associated with the glass transition of its amorphous matrix. A common technique to prevent the rubbery state is the incorporation of biopolymers that contribute to increasing the glass transition temperature or that may exert a steric role. Nevertheless, the chemical composition and physical properties of these biopolymers may affect the quality of the dehydrated product which could compromise its use for specific applications. This work studies the impact of gum Arabic, bamboo fibre, maltodextrin, pea fibre, starch substituted with octenyl succinic groups and native corn starch added to an orange puree, on powder flowability and rehydration behaviour of the freeze-dried fruit powder. As regards the flowability, according to the angle of repose values (37-42 degrees), all powder formulations were considered in the range of 'acceptable' powders. However, both samples containing maltodextrin showed significantly the lowest angle of repose value (37-38 degrees), and therefore a better flowability. Samples containing gum Arabic, bamboo fibre and maltodextrin showed the lower wetting time (175-570 s), which is desired for rehydration, compared to those formulated with OSA (914-1887 s). Moreover, sample with gum Arabic showed the lowest viscosity after rehydration (0.199 Pas), desired to be consumed as a juice. According to the obtained results, if to get an orange puree powder with a good flowability is desired, the use of maltodextrin may be recommended. However, if rehydration is preferred, the use of gum Arabic is more recommended., The authors thank the Ministerio de Economia, Industria y Competitividad of Spain for the financial support given through the Project AGL 2017-89251-R (AEI/FEDER-UE) and the Ministerio de Universidades for the FPU grant (FPU14/02633) awarded to Ms. Andrea Silva.

© 2020 Elsevier Ltd This study investigated starch reduction and replacement by purified cellulose (FC0) and fibrillated cellulose (FC60) which included a comprehensive investigation on dough properties, proofing behaviours, cooking performance, and bread qualities. Replacing flour with FC0 and FC60 was found to strength the doughs without, however, altering the extension of the structural network according to the weak gel model. The relaxation time calculated by the generalised Maxwell model was found to be shorter than the deformation rate during proofing which suggests that the doughs behave like fluids during proofing. The relaxation time was less influenced by the additions of FC0 and FC60. Although the initial stage of proofing was less influenced, the later stage was significantly affected by the additions of FC0 and FC60 which increased dough rigidity and restrained the volume growth. The pasting properties were significantly influenced by the competition for water and volume between FC0/FC60 and flour. The bread qualities were characterised in terms of loaf volume and crumb properties. Loaves containing FC0 and FC60 had smaller specific volume and harder crumb. However, the addition of FC0 and FC60 is beneficial to the generation of a finer crumb structure. Fibrillation process is detrimental to maximise the addition of fibres. However, a small amount of fibrillated cellulose is beneficial to workability and crumb structure.

© 2020 Elsevier Ltd Fibrillated cellulose (FC) and its mixture with psyllium seed husk powder (PSY) were investigated to broaden the applications of these two materials by a novel combination. Purified cellulose was processed by a colloid mill and relatively stable suspensions were obtained. An FC suspension shows localised concentrations appearing as flocculates, which can be promoted by heating or centrifugation. The structures of unheated mixtures of FC and PSY appear to be binary phase dispersions while, after heat treatment, FC fibres were incorporated into PSY gels and form composites. Fibrillation on the FC surface does not influence the structure and rheological property of the composite mixtures while fibre disintegration contributes to a denser structure and higher moduli. Fluorescent images show the attachment of PSY heteroxylan aggregates on cellulose and fibrillated cellulose fibres. The interaction is weak and time-dependent because G’ during cooling was higher than that during heating, and declined back to the same value as the start of heating during an isothermal test at 20 °C. PSY was fractionated according to temperature and only F60 (fraction at 60 °C) clearly associates with the unfibrillated cellulose fibres, possibly via long arabinan sidechains (similar to hairy pectin) or/and backbone (via interaction with helical domains or/and conformational compatibility). The interaction was promoted by fibrillation, potentially trapping PSY heteroxylan aggregates within the cellulose dispersion. With further fibrillation, smaller FC fibres were generated and form interpenetrating particles with whole PSY or PSY fractions. Highly fibrillated cellulose has a higher surface area and smaller fibrils, which significantly increased the interaction resulting in a clumped structure.

Staphylococcus aureus is an important bacterial pathogen that can cause a wide spectrum of diseases in humans and other animals. S. aureus expresses a variety of virulence factors that promote infection with this pathogen. These include cell-surface proteins that mediate adherence of the bacterial cells to host extracellular matrix components, such as fibronectin and fibrinogen. Here, using immunoblotting, ELISA, and surface plasmon resonance analysis, we report that the iron-regulated surface determinant B (IsdB) protein, besides being involved in heme transport, plays a novel role as a receptor for the plasma and extracellular matrix protein vitronectin (Vn). Vn-binding activity was expressed by staphylococcal strains grown under iron starvation conditions when Isd proteins are expressed. Recombinant IsdB bound Vn dose dependently and specifically. Both near-iron transporter motifs NEAT(1) and NEAT(2) of IsdB individually bound Vn in a saturable manner, with K(D) values in the range of 16–18 nm. Binding of Vn to IsdB was specifically blocked by heparin and reduced at high ionic strength. Furthermore, IsdB-expressing bacterial cells bound significantly higher amounts of Vn from human plasma than did an isdB mutant. Adherence to and invasion of epithelial and endothelial cells by IsdB-expressing S. aureus cells was promoted by Vn, and an α(v)β(3) integrin-blocking mAb or cilengitide inhibited adherence and invasion by staphylococci, suggesting that Vn acts as a bridge between IsdB and host α(v)β(3) integrin.

Contribution of methylcellulose (MC), psyllium seed husk powder (PSY), and water addition level to gluten free bread quality and correlations between dough rheological properties and bread qualities were investigated by response surface design and principal component analysis. The generalised Maxwell model was applied to estimate the relaxation frequency of gluten free doughs. The addition of PSY has a complex influence on pasting viscosity at high temperature and an additional peak was observed. MC significantly influenced dough extensibility and work of adhesion, which are good predictors of bread volume and textural properties. Other rheological responses are less significantly correlated to specific volume, but they are sensitive to formulation variations, reflect dough structures and stability, related to proving behaviours, and correlated to loaf concavity. An inappropriate combination of water and hydrocolloids might lead to problems such as low stability of doughs, overexpansion, and weak crumb structure at high water addition levels, or, in contrast, high rigidity of dough, a trap of excessive air during mixing, and restrained gas cell expansion with high hydrocolloid addition and low water addition.

© 2020 Institute of Food Technologists® It is fundamental that students are able to identity where they have developed specific professional competencies during their study. This ensures students can not only articulate their competencies well in job applications and assessments but also draw on their experiences for use in the workplace. The aim of study was to ascertain if desirability of an element or competency as indicated by employers, was reflected in an equivalent level of program content, appropriately perceived by the student. A case study approach mapped elements of the previously developed Competencies for Food Graduate Careers framework against food sciences curricula at University of Nottingham. The mapping process facilitated evaluation of appropriate levels of inclusion of each element in degree programs, by recording types of content and experiences provided, in collaboration with teaching staff. Perspectives of the student experience were captured using an online survey. In addition, guidance from a prior industry survey provided context of the level of desirability for each element across the range of graduate roles in the United Kingdom. The results showed some areas of mismatch, where curricular content did not align with employer expectations or student perceptions. This has informed review of this curriculum, to best reflect “competency development” to meet the needs of the food industry. Recommendations were made to address gaps through enhancement of content, delivery, communication, or assessment. Additionally, the exercise has suggested a more informed development of curricula categorization and coding for future similar mapping activities.

Within a few weeks the world has changed, at the time this text is written (May 2020) more than 3.5 million people have been confirmed cases of COVID-19 and estimations propose up to a hundred times the number of actually infected. A third of the global population is on lockdown and a large part of our global economic activity has stopped. Food and access to food has played a visual role in portraying the impact of the outbreak on our society, with images of empty supermarket shelves appearing in mainstream media. In some countries closed schools resulted in many children not having access to free meals and mobilised a number of charities. While parts of the world are now exiting lockdown and measures start relaxing the near future remains uncertain with more waves of the pandemic expected. Given that there is currently no evidence to show that transmission of COVID-19 could occur through food or food packaging there has been limited discussion on the issue, implications and potential future scenarios within the wider food science community., peer-reviewed

The lipolytic activity in oil body creams as affected by recovery and washing protocols was investigated. The effect of thermal treatment on the hydrolytic activity and physical stability of fresh and aged (up to 30 days) oil body emulsions was studied. The use of alkaline pH solutions (9.5) to soak and grind rapeseeds were more effective reducing the contamination of oil body material from seed proteins/enzymes, compared with neutral pHs. Soaking and grinding seeds with a NaHCO3 solution (0.1 M, pH 9.5) yielded oil bodies with a similar composition to those prepared in urea (9 M); however, the physical stability over storage was compromised due to the presence of hydrolytic enzymes. Heating a dispersion of oil bodies for 6 mins at 95 °C did not alter the physical properties of oil bodies and significantly reduced lipolytic activity (>90% enzyme inactivation), resulting in a stable emulsion.

Staphylococcus epidermidis is a major cause of hospital-acquired infections, especially those related to implanted medical devices. Understanding how S. epidermidis causes disease and devising ways to combat these infections have been hindered by an inability to genetically manipulate clinically significant hospital-adapted strains. Here, we provide the first comprehensive analyses of the barriers to the uptake of foreign DNA in S. epidermidis and demonstrate that these are distinct from those described for S. aureus. Using these insights, we demonstrate an efficient approach for the genetic manipulation of S. epidermidis to enable the study of clinical isolates for the first time., Staphylococcus epidermidis is a significant opportunistic pathogen of humans. Molecular studies in this species have been hampered by the presence of restriction-modification (RM) systems that limit introduction of foreign DNA. Here, we establish the complete genomes and methylomes for seven clinically significant, genetically diverse S. epidermidis isolates and perform the first systematic genomic analyses of the type I RM systems within both S. epidermidis and Staphylococcus aureus. Our analyses revealed marked differences in the gene arrangement, chromosomal location, and movement of type I RM systems between the two species. Unlike S. aureus, S. epidermidis type I RM systems demonstrate extensive diversity even within a single genetic lineage. This is contrary to current assumptions and has important implications for approaching the genetic manipulation of S. epidermidis. Using Escherichia coli plasmid artificial modification (PAM) to express S. epidermidis hsdMS, we readily overcame restriction barriers in S. epidermidis and achieved electroporation efficiencies equivalent to those of modification-deficient mutants. With these functional experiments, we demonstrated how genomic data can be used to predict both the functionality of type I RM systems and the potential for a strain to be electroporation proficient. We outline an efficient approach for the genetic manipulation of S. epidermidis strains from diverse genetic backgrounds, including those that have hitherto been intractable. Additionally, we identified S. epidermidis BPH0736, a naturally restriction-defective, clinically significant, multidrug-resistant ST2 isolate, as an ideal candidate for molecular studies.

The potential of blackcurrant pomace as a raw material for the extraction of dietary fibre was evaluated using two pomaces one sourced from the UK and one from Poland. A fractionation protocol was designed to isolate and subsequently quantify the soluble and insoluble dietary fibre fractions. Blackcurrant pomace and isolated pectins, hemicelluloses and celluloses were assessed by means of sugar compositional analysis, spectroscopy, size exclusion chromatography and dilute solution viscometry. The blackcurrant pomaces presented considerable amounts of dietary fibre with soluble fibre ranging from 25-30% w/w and insoluble dietary fibre accounting for about 47% w/w for both pomaces. Blackcurrant pomaces differed in the amount of extracted pectins with an almost two times higher pectin yield obtained from blackcurrant pomace sourced from Poland. The hemicellulosic polysaccharide content was 15% w/w whereas the amount of cellulosic fraction varied from 14-17% w/w. Pectins isolated from both blackcurrant pomaces were LM pectins with a degree of esterification in the range of 11-38%. The work has identified that dietary fibres obtained from blackcurrant pomace had desirable ratio of insoluble to soluble fibre and are a potential new source of dietary fibre.

Oat bran protein flour (OBPF), containing protein, starch, and lipid as major constituents, was ball milled and subsequently evaluated on structural conformation, thermal properties, particle size distributions, and rheological properties. Prior to ball milling, characterisation of OBPF were conducted by means of Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) showing the existence of aggregated protein and starch-lipid complexes as predominant constituents of OBPF. Ball milling altered structural conformations of both protein and starch. Moreover, increase of ball milling time gradually decreased the transition enthalpy changes of amylose-lipid complexes upon heating which can be related to disruption of amylose-lipid complexes helical structure. Ball milling at higher speed resulted to smaller average particle size distributions of OBPF. Dynamic mechanical spectra of concentrated dispersions containing ball milled OBPF exhibited lower storage (G′) and loss (G″) moduli compared to control sample due to reduced particles volume packing. Moduli-frequency sweep data satisfactory fitted the Power Law’s model.

The aim of this work was to analyse the effect of bacterial cellulose fibrils (BCF) on the gelatinization profile and pasting properties of starches from different sources (wheat, maize and waxy maize) and amylose contents. Blends of 8% starch with different BCF levels (0, 0.5, 2, 6 and 10% based on the dry weight of starch) were prepared and tested by Rapid Visco-Analysis (RVA), Differential Scanning Calorimetry (DSC) and both Optical and Polarized Light Microscopy. Results showed that BCF produce a significant modification of pasting properties. The pasting temperature was reduced but viscosities (peak, final, trough, breakdown and final) increased. The reduction in pasting temperature at the highest BCF addition was 200C higher for maize and wheat starches but only 20C higher for waxy maize starch. In contrast to the pasting temperature, the gelatinisation temperature by DSC for all three starches slightly varied upon BCF addition, but the gelatinisation enthalpy was reduced to a greater extent than values reported for the addition of other hydrocolloids to starch blends. Optical and polarized light microscopy showed the presence of domains rich in starch and highly aggregated BCF in all three starches evaluated. The increase in viscosity and decrease in pasting temperature are discussed in terms of changes in starch concentrations in the starch rich domain. These results open interesting perspectives in the use of bacterial cellulose and plant cell walls to design novel bio-composites to structure foods.

Suspensions of gel particles which are pourable or spoonable at room temperature can be created by shearing a gelling biopolymer through its gelation (thermal or ion mediated) rather than allowing quiescent cooling – thus the term ‘fluid gel’ may be used to describe the resulting material. As agar gelation is thermoreversible this type of fluid gel is able to be heated again to melt agar gel particles to varying degrees then re-form a network quiescently upon cooling, whose strength depends on the temperature of re-heating, determining the amount of agar solubilised and subsequently able to partake in re-gelation. Using this principle, for the first time fluid gels have been applied to a high viscosity 3D printing process wherein the printing temperature (at the nozzle) is controllable. This allows the use of ambient temperature feedstocks and by altering the nozzle temperature, the internal nature (presence or absence of gel particles) and gel strength of printed droplets differs. If the nozzle prints at different temperatures for each layer a structure with modulated texture could be created.

The impact of different cellulosic microstructures formed by highly entangled fibre networks 8 were studied for food applications as dietary fibre. This paper reports the impact of microstructure on the rheological and sensory behaviour of the aqueous suspensions of particulate and fibrillated forms of softwood cellulosic fibres, and were compared with citrus fibre. An aqueous suspension of cellulosic fibres shows stable viscoelastic gel-like behaviour as a function of frequency. The particulate form of cellulosic fibres showed lowest shear viscosity as compared to the entangled network system at comparable concentrations. To provide further insight into the relationship between the structure of cellulosic fibre systems and perception of salt taste in aqueous suspensions of softwood cellulosic fibres (fibrillated and particulate form) and citrus fibres with matched shear viscosities were studied. A hypothesis to explain why softwood cellulosic fibre (CTE) with entangled network structure prolongs the taste perception is presented.

Hybrid meat analogues, whereby a proportion of meat has been partially replaced by more sustainable protein sources, have been proposed to provide a means for more sustainable diets in the future. Consumer testing was conducted to determine consumer acceptability of different formulations of Hybrid beef burgers and pork sausages in comparison with both meat and meat‐free commercial products. Acceptability data were generated using the 9‐point hedonic scale. Check‐all‐that‐apply (CATA) questioning was used to determine the sensory attributes perceived in each product as well as information on the attributes of consumers’ ideal products. It was identified that Hybrid products were generally well liked among consumers and no significant differences in consumer acceptability (p > .05) were identified between Hybrid and full meat products, whereas meat‐free products were found to be less accepted. However, Hybrid sausages received higher acceptability scores (6.00–6.51) than Hybrid burgers (5.84–5.92) suggesting that format may have a large impact on consumer acceptability of Hybrid products. Correspondence Analysis (CA) indicated that Hybrid products were grouped with meat products in their sensory attributes. Penalty analysis found that a “meaty flavor” was the largest factor driving consumer acceptability in both burgers and sausages. Cluster analysis of consumer acceptability data identified key differences in overall acceptability between different consumer groups (consumers who only eat meat products and consumers who eat both meat and meat‐free products). The Hybrid concept was found to bridge the acceptability gap between meat and meat‐free products; however, further product reformulation is required to optimize consumer acceptability.

The major targets for antibiotics in staphylococci are (i) the cell envelope, (ii) the ribosome and (iii) nucleic acids. Several novel targets emerged from recent targeted drug discovery programmes including the ClpP protease and FtsZ from the cell division machinery. Resistance can either develop by horizontal transfer of resistance determinants encoded by mobile genetic elements viz plasmids, transposons and the staphylococcal cassette chromosome or by mutations in chromosomal genes. Horizontally acquired resistance can occur by one of the following mechanisms: (i) enzymatic drug modification and inactivation, (ii) enzymatic modification of the drug binding site, (iii) drug efflux, (iv) bypass mechanisms involving acquisition of a novel drug-resistant target, (v) displacement of the drug to protect the target. Acquisition of resistance by mutation can result from (i) alteration of the drug target that prevents the inhibitor from binding, (ii) derepression of chromosomally encoded multidrug resistance efflux pumps and (iii) multiple stepwise mutations that alter the structure and composition of the cell wall and/or membrane to reduce drug access to its target. This review focuses on development of resistance to currently used antibiotics and examines future prospects for new antibiotics and informed use of drug combinations.

The Staphylococcus aureus fibrinogen binding MSCRAMM (Microbial Surface Components Recognizing Adhesive Matrix Molecules), ClfA (clumping factor A) is an important virulence factor in staphylococcal infections and a component of several vaccines currently under clinical evaluation. The mouse monoclonal antibody aurexis (also called 12-9), and the humanized version tefibazumab are therapeutic monoclonal antibodies targeting ClfA that in combination with conventional antibiotics were effective in animal models but showed less impressive efficacy in a limited Phase II clinical trial. We here report the crystal structure and a biochemical characterization of the ClfA/tefibazumab (Fab) complex. The epitope for tefibazumab is located to the “top” of the N3 subdomain of ClfA and partially overlaps with a previously unidentified second binding site for fibrinogen. A high-affinity binding of ClfA to fibrinogen involves both an interaction at the N3 site and the previously identified docking of the C-terminal segment of the fibrinogen γ-chain in the N2N3 trench. Although tefibazumab binds ClfA with high affinity we observe a modest IC50 value for the inhibition of fibrinogen binding to the MSCRAMM. This observation, paired with a common natural occurring variant of ClfA that is not effectively recognized by the mAb, may partly explain the modest effect tefibazumab showed in the initial clinic trail. This information will provide guidance for the design of the next generation of therapeutic anti-staphylococcal mAbs targeting ClfA., Highlights • The crystal structure of the monoclonal antibody tefibazumab in complex with ClfA (Clumping factor A) of S. aureus • Biochemical studies reveal a second binding site for fibrinogen in ClfA partially overlapping the tefibazumab epitope. • An explanation for tefibazumab modest effect in a clinical trial compared to the monoclonal's efficacy in animal models The S. aureus fibrinogen binding surface protein ClfA (Clumping factor A) is an important virulence factor and a target in several staphylococcal experimental vaccines and immunotherapeutic. One monoclonal antibody to ClfA called aurexis showed great promise in animal models for the treatment of staphylococcal infections. However, in a limited phase II clinical trial the efficacy was less impressive. We have solved the structure of the Fab fragment of tefibazumab (the humanized version of aurexis) in complex with the fibrinogen binding region of ClfA. The tefibazumab epitope partially overlaps with a previously unknown second fibrinogen binding site on ClfA. Biochemical analysis show that although tefibazumab binds to ClfA with high affinity the IC50 concentration for fibrinogen binding is modest. Furthermore, analysis of sequence variations in ClfA shows that some clinically important strains are poorly recognized by tefibazumab. These observations may partially explain the modest efficacy observed for tefibazumab in the clinical trial but provide a structural base for the design of more potent inhibitors., Graphical Abstract Image 4

Staphylococcus epidermidis is a ubiquitous commensal of human skin. The widespread use of indwelling medical devices in modern medicine provides an opportunity for it to cause infections. Disease causing isolates can come from many different genetic backgrounds. Multiply antibiotic resistant strains have spread globally. S. epidermidis has a smaller repertoire of cell wall anchored (CWA) surface proteins than Staphylococcus aureus. Nevertheless, these CWA proteins promote adhesion to components of the extracellular matrix including collagen, fibrinogen, and fibronectin and contribute to the formation of biofilm. The A domain of the accumulation associated protein Aap can promote adhesion to unconditioned biomaterial but must be removed proteolytically to allow accumulation to proceed by homophilic Zn2+-dependent interactions. Mature biofilm contains amyloid structures formed by Aap and the small basic protein (Sbp). The latter contributes to the integrity of both protein and polysaccharide biofilm matrices. Several other CWA proteins can also promote S. epidermidis biofilm formation.

Staphylococcus epidermidis is a significant opportunistic pathogen of humans. Molecular studies in this species have been hampered by the presence of restriction-modification (RM) systems that limit introduction of foreign DNA. Here we establish the complete genomes and methylomes for seven clinically significant, genetically diverse S. epidermidis isolates and perform the first systematic genomic analyses of the type I RM systems within both S. epidermidis and Staphylococcus aureus. Our analyses revealed marked differences in the gene arrangement, chromosomal location and movement of type I RM systems between the two species. Unlike S. aureus, S. epidermidis type I RM systems demonstrate extensive diversity even within a single genetic lineage. This is contrary to current assumptions and has important implications for approaching the genetic manipulation of S. epidermidis. Using Escherichia coli plasmid artificial modification (PAM) to express S. epidermidis hsdMS, we readily overcame restriction barriers in S. epidermidis, and achieved transformation efficiencies equivalent to those of modification deficient mutants. With these functional experiments we demonstrate how genomic data can be used to predict both the functionality of type I RM systems and the potential for a strain to be transformation proficient. We outline an efficient approach for the genetic manipulation of S. epidermidis from diverse genetic backgrounds, including those that have hitherto been intractable. Additionally, we identified S. epidermidis BPH0736, a naturally restriction defective, clinically significant, multidrug-resistant ST2 isolate as an ideal candidate for molecular studies.ImportanceStaphylococcus epidermidis is a major cause of hospital-acquired infections, especially those related to implanted medical devices. Understanding how S. epidermidis causes disease and devising ways to combat these infections has been hindered by an inability to genetically manipulate “hospital-adapted” strains that cause clinical disease. Here we provide the first comprehensive analyses of the mechanisms whereby S. epidermidis resists the uptake of foreign DNA and demonstrate that these are distinct from those described for S. aureus. Until now it had been assumed that these are the same. Using these insights, we demonstrate an efficient approach for the genetic manipulation of S. epidermidis to enable the study of clinically relevant isolates for the first time.

The microbial surface components recognizing adhesive matrix molecules (MSCRAMMs) are a family of proteins that are defined by the presence of two adjacent IgG-like folded subdomains. These promote binding to ligands by mechanisms that involve major conformational changes exemplified by the binding to fibrinogen by the ‘dock-lock-latch’ mechanism or to collagen by the ‘collagen hug’. Clumping factors A and B are two such MSCRAMMs that have several important roles in the pathogenesis of Staphylococcus aureus infections. MSCRAMM architecture, ligand binding, and roles in infection and colonization are examined with a focus on recent developments with clumping factors.

Cheddar cheese predicted to develop into different quality classes has been evaluated by time domain Nuclear Magnetic Resonance, Thermogravimetric analysis and quantitative sensory analysis. The water and fat proton signals in the transverse relaxation decay curves have been deconvoluted. Proton transverse relaxation values for both the water and fat fractions decrease and the relative %age of the proton peak area, predominantly from the fat increases over a 450-day ripening period. The thermodynamic free water percentage increases during maturation. Water and fat attributes can distinguish between Cheddar cheese batches after 56 days. Cheese batches which have lower transverse relaxation values for the water and fat proton fractions and a higher relative %age of the proton peak area predominantly from fat at 56 days, mature after 270 days to be more yellow, rubbery and smooth, have a less sour and lingering aftertaste and are also harder to form into a cheese ball.

Binder jetting is a form of additive manufacturing (AM) in which a powder component is deposited in layers sequentially with an ‘ink’. The ink acts to selectively bind certain areas of a given layer of powder (physically or chemically) so that on completion of the printing process, a cohesive 3D structure may be removed from a surrounding bulk of unbound powder. Agglomeration processes are well known amongst food scientists and integral to many commercially available products on different length scales, from rehydratable powdered drinks or soups to cereal-based clusters; thus, this method of AM is well suited for use with edible feedstocks. This chapter will cover considerations for both powder and ink development, interactions during and after printing as well as the current status and outlook for the widespread use of this particular AM technology for the food industry.

Staphylococcus aureus is a major cause of corneal infections that can cause reduced vision, even blindness. Secreted toxins cause tissue damage and inflammation resulting in scars that lead to vision loss. Identifying tissue damaging proteins is a prerequisite to limiting these harmful reactions. The present study characterized a previously unrecognized S. aureus toxin. This secreted toxin was purified from strain Newman &Delta, hla&Delta, hlg, the N-terminal sequence determined, the gene cloned, and the purified recombinant protein was tested in the rabbit cornea. The virulence of a toxin deletion mutant was compared to its parent and the mutant after gene restoration (rescue strain). The toxin (23 kDa) had an N-terminal sequence matching the Newman superantigen-like protein SSL1. An SSL1 homodimer (46 kDa) had proteolytic activity as demonstrated by zymography and cleavage of a synthetic substrate, collagens, and cytokines (IL-17A, IFN-&gamma, and IL-8), the protease was susceptible to serine protease inhibitors. As compared to the parent and rescue strains, the ssl1 mutant had significantly reduced virulence, but not reduced bacterial growth, in vivo. The ocular isolates tested had the ssl1 gene, with allele type 2 being the predominant type. SSL1 is a protease with corneal virulence and activity on host defense and structural proteins.

The aim of this study was 1) to investigate the influence of polymeric additives such as carboxyl methyl cellulose (CMC) and locust bean gum (LBG) added before and after homogenisation on the moisture uptake of microfibrillar cellulose (MFC) in the dry and semi-wet state; and 2) to further understand the thermally induced structural transitions of low moisture MFC in the presence of the polymeric additives. A higher moisture content in the highly dense MFC network maintains the fibrillated network structure, which is lost during the drying process resulting in MFC aggregates. The addition of polymeric additives results in the regaining of the structure upon redispersion of the dry material with CMC being more effective than LBG). Results also indicated that CMC has a high level of compatibility with MFC, whereas LBG appears to have limited distribution in the MFC dense microfibrillar network and probably exists as a separate phase when added after homogenisation, however co-processing of LBG and cellulose significantly changed this behaviour. The presence of low-temperature transitions in MFC/additives/water mixtures indicates the involvement of these semi-flexible polymeric additives in the formation of liquid crystals when added to MFC in low moisture environments (2% and 20% w/w). An insight is offered into the theory of surface interactions between MFC and polymeric additives, which prevents the agglomeration of microfibrils present in the highly fibrillated suspension upon drying.