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The aim of the study was to investigate the properties of sodium caseinate dispersions and oil-in-water emulsions obtained from cows' milk of either A1/A1, A1/A2, or A2/A2 β-casein phenotype. Protein structural characterisation was examined using Fourier Transform Infrared and Nuclear Magnetic Resonance spectroscopies, with physicochemical and interfacial properties assessed by analysing adsorbed protein content, hydrophobicity, solubility, and emulsion stability of the samples. Results showed variations in the secondary structure of all samples dependent of the presence of A1 or A2 β-caseins. The main differences included greater amounts of α-helix and β-sheet in A1/A1 and A1/A2 sodium caseinate dispersions that influenced their lower solubility, while random coils/polyproline II helixes were found only in A2/A2 sodium caseinate dispersion. In contrast, upon adsorption on the interface of A2/A2 sodium caseinate emulsion, the protein adopted ordered conformational motifs. This conformational shift supposedly arose from structural differences between the two β-casein proteoforms, which most likely enhanced the emulsion properties of A2/A2 sodium caseinate compared to either A1/A1 or A1/A2 sodium caseinates. The A2 β-casein in both, A1/A2 and A2/A2 sodium caseinates, appears to be able to more rapidly reach the oil droplet surface and was more efficient as emulsifying agent. The current results demonstrated that the conformational rearrangement of proteins upon adsorption to emulsion interfaces was dependent not only on hydrophobicity and on solubility, but also on the conformational flexibility of A1/A1, A1/A2, and A2/A2 β-casein phenotypes. These findings can assist in predicting the behaviour of sodium caseinates during relevant industrial processing.

Background Complex polymorphisms in the polypeptide chain of bovine β-casein are responsible for the genetic variants that give rise to different bioactive peptides during in vitro and ex vivo digestion, or food fermentation. One specific group of bioactive peptides, known as β-casomorphins, are opioid-agonists for μ-receptors and have been suggested to assume an active role in the development of various non-communicable diseases, including diabetes mellitus, cardiovascular diseases, neurological disorders, pulmonary inflammation, to name a few. Their potential bioactivity and role in human health is dependent on their release from the latent form within the primary structure of β-casein, which can occur during the manufacture of dairy products or during gastric and intestinal digestion. Consequently, β-casomorphins can be either completely hydrolysed or absorbed in the gut or be transferred into the blood stream and internal organs in their intact form. Their biological function as opioid agonists is expressed in the gut, thus upon epithelial translocation they may affect various physiological states, such as causing gastrointestinal issues, bloating, and lactose intolerance. Scope and approach This review evaluated the possible disadvantages and potential beneficial effects of β-casomorphins on human health, within the scope of in vitro and ex vivo studies. Applying a systematic approach, a literature search was performed across four electronic databases (Scopus, Web of Science, PubMed, and Cochrane) to identify suitable studies. Key findings and conclusions The data mined from in vitro and ex vivo trials on the health impact of β-casomorphins is both inconclusive and limited to completely support the possible adverse or potential beneficial health effects of β-casomorphins. These peptides are usually further cleaved in the gut, which prevents their migration across the gut-blood-brain barrier. Nevertheless, in some individuals that are immunocompromised, their condition increases permeability of the gut barrier often referred to as a "leaky gut" condition. Thus, the absorption of β-casomorphins appears possible. This may indicate that the presence of β-casomorphins can affect gastrointestinal functions only. However, since the overall concern with β-casomorphins appears debatable and not well defined, more experimental trials are required to investigate the metabolic pathways of these identified peptides, their release during digestion, and subsequent fate after the digestion process. Consequently, repeatability of the findings under a number of other laboratory conditions is required before the data can be fully substantiated. Due to the rapidly evolving nature of the issue and emerging studies in this field, further exploration into the bioactivity of β-casomorphins is warranted.

Background A number of randomised in vivo trials have to date investigated the health impacts of the genetic variants A1 and A2 of bovine β-casein. The primary difference between these two genetic variants is the mutation leading to an amino acid exchange at a position 67 in the peptide chain. This systematic review evaluated the effects of bovine milk, β-casein and pure β-casomorphin7, in the form of orally administered nutritional ingredients, on possible incidence and risk for chronic digestive discomfort and development of incurable conditions and diseases in human and animal randomised controlled trials. Scope and approach Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist, searches were performed for publications across 7 electronic databases (Scopus, Embase, Web of Science, Medline, EBSCO, PubMed, and Cochrane) up to and until July 2020, to identify randomised controlled trials. The subsequent search results were screened for relevance firstly by title, then abstract, and the chosen ones by full text, with additional screening of included articles reference lists. Key findings and conclusions In total 2006 peer-reviewed journal articles were identified and after applying exclusion criteria, 19 studies were deemed suitable for inclusion. Human-based and animal-based results from the clinical in vivo studies demonstrated that consumption of A2 β-casein milk can lead to improved tolerance of milk via decline in the ubiquity of gut related discomfort. However, the exact mechanism for these effects or specific individuals that may benefit from A2 β-casein milk as opposed to A1 β-casein milk is still poorly understood. Notably, consumption of A2 β-casein milk had very low to completely no effect on the other health statuses investigated, particularly non-communicable diseases, such as cardiovascular diseases, neurological disorders, and diabetes. Based on current data, there is not sufficient evidence to merit public health authority recommendations related to the consumption and health associations of A1 β-casein milk or A2 β-casein milk. Interestingly, regardless of the scientific evidence between A2 β-casein milk and health, this milk continues to gain prominence on the market, thus further functional research is required to understand the mechanisms of action of these identified peptides and gene variants and any implications A1 or A2 β-casein milk may have on human health and techno-functional properties of milks.

Changes in the pH of skim milk and skim milk ultrafiltration permeate on heating from 25 to 140 °C were examined. Results showed that the decrease in pH with increase in temperature up to 140 °C was not linear. Hydrogen ion release due to changes in the milk mineral balance were responsible for the reduction in pH with increase in temperature. The presence of milk proteins offered little buffering against the drop in pH. The precipitation of calcium phosphate resulted in sediment in milk permeate heated above ∼70 °C, but this did not occur in skim milk, with the pH remaining lower in milk permeate after heat treatment when measured at 25 °C. This study has shown that in-line pH measurements of milk at ultra-high temperatures is feasible, and could prove useful at laboratory and pilot-scale for studying interactions within, and stability of, more complex formulations with added minerals.

Calcium chelating agents, such as sodium hexametaphosphate (SHMP), can be added to milk protein solutions to aid in rehydration; however, this leads to a concomitant increase in solution viscosity due to micelle swelling/dissociation. Crosslinking casein proteins using transglutaminase (TGase) can help retain casein micelle structure and maintain low viscosity. This study aimed to determine the water sorption and hydration properties of milk protein concentrate (MPC) powders, as influenced by the crosslinking of milk proteins and the addition of SHMP. Crosslinked casein protein (TG-MPC) powders without SHMP addition had improved wettability, water sorption and water diffusion compared to the non-crosslinked control (C-MPC) powder. All powders containing SHMP were found to have increased water sorption compared to control powders without SHMP addition. Powder dissolution data showed that increasing SHMP content increased powder rehydration particle size, compared to powders without SHMP addition, indicating increased particle swelling due to increased water absorption.

peer-reviewed This work aimed to model the effect of heat treatment on viscosity of milk protein concentrate (MPC) using kinetic data. MPC obtained after ultrafiltration was subjected to different time-temperature heat treatment combinations. Heat treatment at high temperature and short time (i.e., 100 or 120 °C×30 s) led to a significant increase in viscosity in MPC systems. Second-order reaction kinetic models proved a better fit than zero- or first-order models when fitted for viscosity response to heat treatment. A distinct deviation in the slope of the Arrhenius plot at 77.9 °C correlated to a significant increase in the rate of viscosity development at temperatures above this, confirming the transition of protein denaturation from the unfolding to the aggregation stage. This study demonstrated that heat-induced viscosity of MPC as a result of protein denaturation/aggregation can be successfully modelled in response to thermal treatment, providing useful new information in predicting the effect of thermal treatment on viscosity of MPC.

peer-reviewed Direct supersonic steam injection, direct steam infusion, and indirect tubular heating were each applied to protein-enriched skim milk-based beverages with 4, 6 and 8% (w/w) total protein, and the effect of final heat temperature on the physical properties of these beverages was investigated. Supersonic steam injection resulted in significantly lower levels of denaturation of β-lactoglobulin (34.5%), compared to both infusion (76.3%) and tubular (97.1%) heating technologies. Viscosity, particle size and accelerated physical stability of formulations did not differ significantly between the heating technologies, while noticeable colour differences due to heat treatment (mainly attributed to increasing b* value) were observed, particularly for tubular heating. Overall, the extent of protein denaturation in high-protein dairy products was significantly influenced by the particular heating technology applied. The application of supersonic steam injection technology, with rapid heating and high shear characteristics, may enable differenciated product characteristics for ready-to-drink ambient-delivery high-protein dairy beverages. Industrial relevance: The design and application of novel direct supersonic steam injection technology was comprehensively studied and found to provide significant benefits over direct steam infusion and indirect tubular heating technologies for skim milk-based protein beverages. This type of injection heating system resulted in heat-treated formulations with lower levels of denatured whey proteins, compared to tubular and infusion heating, offering an alternative opportunity to the industry in terms of producing shelf-stable dairy protein beverages.

This study highlights differences in conformational and physicochemical characteristics of bovine skim milk and micellar casein from cows of different β-casein phenotypes. These genetic variants have been one of the predominant topics among dairy researchers due to their differences in β-casein structure, and thus their potential effects on dairy processing and human health. For characterising differences in milk protein structure, Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (1H NMR) spectroscopies combined with chemometric analysis were used. Additionally, physiochemical properties such as mineral content, particle size, and electrostatic charge in skim milk and micellar casein samples were analysed at 4 and 20 ᵒC. Results showed variation in the secondary structure of all three genetic variants independent of temperature. Moreover, the main differences involved a higher level of β-turn and α-helical structures in A1/A1 β-casein milk, while intermolecular β-sheets were more numerous in A1/A2 β-casein milk, whereas random or polyproline II (PPII) structures were more common in A2/A2 β-casein milk. Temperature slightly affected these differences, which was due to the dissociation of β-casein from the micelle at low temperature. In addition, A2/A2 β-casein milk and its micellar casein had a larger average particle size, which resulted in a lower negative ζ-potential. The A2/A2 β-casein samples contained greater amounts of phosphorus and less calcium compared to the other genetic variants of milk and their micellar caseins. The results also indicated that a combination of FTIR and 1H NMR spectroscopies could be used to establish conformational differences in milk and micellar caseins of different genetic variants.

peer-reviewed The effect of pH, adjusted using either hydrochloric acid (HCl), citric acid or sodium hydroxide, on calcium ion (Ca2+) activity, and consequent changes in viscosity and heat coagulation time (HCT) of milk protein concentrate (MPC) was investigated. Reducing the pH of MPC dispersions resulted in a reduction in their viscosity, which subsequently increased during heat treatment. The maximum heat stability of MPC was observed at pH 6.7. Reducing the pH of MPC from 6.7 to 6.2 resulted in a significant (P < 0.05) increase in Ca2+ activity, and reduction in HCT. Such changes were more extensive using HCl compared with citric acid. Increasing the pH greater than 6.7 also led to a reduction in HCT but a decrease in Ca2+ activity. These results demonstrate the importance of pH adjustment, and choice of acidulant, on Ca2+ activity, viscosity, and heat coagulation properties of MPC concentrates during processing.

peer-reviewed Microfiltration (MF) of skim milk, when combined with diafiltration (DF), facilitates the manufacture of liquid micellar casein concentrate (MCC), which can be spray-dried into high-protein (≥80% protein, dry-basis) powders. MCC powders rehydrate slowly, which is typically considered a defect by end-users. This study compared the impact of cold (

The aim of this study was to evaluate the effectiveness of an in-line hydrodynamic cavitation (HC) system, for rehydration of milk protein concentrate powders (MPC) at semi-industrial pilot scale. MPC powder was dispersed in water at 50 °C at 20% (w/w) dry matter (DM) with two commonly used high-shear powder inductors/mixers. The MPC dispersions created were then passed through the HC system to assess subsequent hydration behaviour of the MPC powders. Particle size distribution (PSD) of MPC dispersions prepared using conventional high-shear mixing indicated that complete rehydration of MPC powders was not achieved, with an average D90 and D[4,3] values of 21.17 μm and 5.62 μm respectively, observed in MPC dispersions. In contrast MPC dispersions subjected to HC had a PSD indicative of complete rehydration, with an average D90 and D[4,3] values of 0.45 μm and 0.19 μm, respectively. Apparent viscosity decreased significantly (p≤.05) post HC compared to dispersions subjected to conventional high shear mixing. Phase separation profiles showed that HC treated MPC dispersions had increased stability to sedimentation compared to high-shear treated samples. Wetting, immersion, dissolution and solubilisation of high protein powders occurred instantaneously (and simultaneously) during HC. This emerging technology has the potential to achieve complete rehydration of powders in significantly less time than conventional rehydration processes employed by dairy and other industries.

Due to their excellent nutritional (e.g., high calcium) and functional (e.g., heat stability and gelation) properties, the use of protein-enriched, micellar casein-dominant dairy powders, including milk protein concentrate/isolate and micellar casein concentrate, has increased considerably among food and beverage manufacturers. However, the poor and often inconsistent rehydration properties of these powders in water, specifically their low dispersibility and solubility (attributed to protein–protein interactions related to the high proportion of micellar casein), remains a significant challenge. This review provides a detailed analysis of the main physical (e.g., injection of gas, ultrasonication) and chemical (e.g., ion exchange, pH adjustment) processing strategies that have been applied, at both laboratory and pilot-scale, to enhance the rehydration performance of high-protein, micellar casein-dominant dairy powders. The information provided will support the advancement of dairy ingredient research and the technological development of nutritional powders that can be used across several industrial applications.

Milk concentrate (MC) viscosity is a key process control parameter in the manufacture of dairy based powders that affects both process efficiency and powder functionality. If the viscosity of MC is too high, various processing issues can arise, i.e., pump blockages, fouling, poor atomisation, product rework and production downtime. Viscosity of MC is dependent on various intrinsic (e.g., total solids content, protein: lactose ratio, mineral profile, pH) and extrinsic (e.g., temperature, agitation, high shear) parameters. It is therefore necessary to understand the effects of these parameters on the viscosity of MC to maintain an optimal process. This review focuses on outlining the parameters that affect the viscosity of MC and recent advances in processing strategies to reduce viscosity of MC prior to spray drying during powder manufacture.

Reconstituted milk protein concentrate (MPC; 80% protein) was mixed with lactose (MPC-Lac) or milk permeate (MPC-Perm) to 20% dry matter (DM) before been evaporated to 45% DM and subsequently spray dried. The pH of protein solutions, measured during evaporation from 20 to 45% DM at 50 °C, decreased from pH 6.64 to pH 6.53 and from 6.1 to 5.95 for MPC-Lac and MPC-Perm, respectively. The particle size and viscosity were greater in MPC-Perm than MPC-Lac solutions after evaporation. However, the heat stability of rehydrated MPC-Perm powder (3.5% protein) were significantly higher than MPC-Lac at pH values between 6.4 and 6.8, which may be attributed to the lower calcium ion concentration in MPC-Perm than in MPC-Lac. This study highlighted the complexity of mineral addition and phase distribution in protein-standardised milk systems; whereby higher levels of mineral addition contribute to viscosity and age thickening, but not necessarily lower heat stability.

The protein composition of bovine skim milk was modified using pilot scale membrane filtration to produce a whey protein-dominant ingredient with a casein profile closer to human milk. Bovine skim milk was processed at low (8.9 °C) or high (50 °C) temperature using ceramic microfiltration (MF) membranes (0.1 μm mean pore diameter). The resulting permeate stream was concentrated using polyethersulfone ultrafiltration (UF) membranes (10 kDa cut-off). The protein profile of MF and UF retentate streams were determined using reversed phase-high performance liquid chromatography and polyacrylamide gel electrophoresis. Permeate from the cold MF process (8.9 °C) had a casein:whey protein ratio of ∼35:65 with no α S - or κ-casein present, compared with a casein:whey protein ratio of ∼10:90 at 50 °C. This study has demonstrated the application of cold membrane filtration (8.9 °C) at pilot scale to produce a dairy ingredient with a protein profile closer to that of human milk.

This study investigated the influence of injecting nitrogen (N2) gas under high pressure into milk protein concentrate (80%, w/w, protein; MPC) prior to spray drying and examining the physical and bulk handling properties of regular (non-agglomerated) and agglomerated powders. MPC powders produced using the N2 injection (NI) process had significantly lower bulk density and flowability, higher wall friction angles and increased levels of interstitial and occluded air. Agglomerated MPC powders had higher flow index values, lower wall friction angles, but were more friable, compared to regular powders. Surface composition analysis of MPC powders showed that NI caused fat to preferentially migrate to the surface in comparison to powders spray dried without NI. The results obtained in this study demonstrate that the injection of N2 into liquid MPC directly prior to spray drying, as well as agglomeration by fines return, can produce ingredients with unique particle and bulk powder properties.

Pea protein isolate (PPI) is used in many food formulations, due to its low cost, commercial availability and excellent amino acid profile. The objective of this study was to determine the emulsification properties of PPI. Particle size of PPI powders showed neither temperature (25-65°C) nor time (up to 24h) increased solubilisation of powder particles during mixing. Heating PPI dispersions (10%, w/w, protein) from 45 to 90°C led to an increase in storage modulus (G'; Pa) at 71°C, indicating the onset of protein aggregation. Gel formation occurred at 79°C (G'>1Pa). Pea protein-stabilised emulsions made using homogenization (15MPa; 1 pass) or microfluidization (50MPa; 1 pass) resulted in the formation of cold-set gels, with gel strength increasing with increasing oil concentration and fluidic pressure. Droplet size and viscosity of pea protein-stabilised emulsions decreased and increased, respectively, with increasing ultrasonication time. Overall, ultrasonication (

Composition and relative humidity (RH) can have a profound impact on the physical (flowability, stickiness) and functional (reconstitution) properties of milk powder (MP) and therefore its quality, storage stability and shelf-life. Conventional microscopic techniques are not capable of dynamically imaging the effect of RH on MP at high magnification. The aim of this study was to develop a novel method to characterise in-situ and in real time the hydration and reconstitution of five spray-dried milk protein concentrates (MPCs) using an Environmental Scanning Electron Microscope (ESEM). ESEM was employed to observe the surface microstructure of MPC powders with varying protein content (38.63%–80.94%, w/w), at various RH values ranging from 35% to over 100%. MPC powders were imaged by an ESEM without any prior preparation, and with minimal physical sample alteration, thus providing fundamental insights into MPC hydration and reconstitution. ESEM surface analysis showed particle swelling in all MPCs, and that with increasing protein content, hydration and reconstitution efficiency decreased. For the first time, dynamic particle surface fusion was observed. Such fusion can result in stickiness and caking over time. ESEM methods developed here may provide mechanistic insights into the effects of RH during storage. Surface re-arrangement was also observed in all MPCs, but was impeded in MPC70 and MPC80 thus indicating that this is the rate limiting step for MPC reconstitution. This work validates the use of an ESEM to dynamically characterise MPC powder hydration and reconstitution in-situ and in real-time, at both high magnification and spatial resolution.

The functional properties of milk protein concentrate (MPC) powders are often hindered by their poor solubility. Calcium chelating salts have been shown to improve powder solubility, but generally their action contributes to higher viscosity due to disintegration of casein micelles and higher levels of serum-phase calcium. To help mitigate increases in viscosity associated with calcium chelation, transglutaminase (TGase), an enzyme that covalently crosslinks protein, was employed in an effort to stabilise the casein micelle structure. Sodium hexametaphosphate (SHMP) was added to control (C-MPC) and TGase crosslinked MPC (TG-MPC) dispersions at concentrations of 5, 12.5 and 25 m m prior to analysis. TG-MPC dispersions had lower viscosity than C-MPC dispersions across all SHMP concentrations studied. Crosslinking limited micelle dissociation on SHMP addition and led to greater retention of the white colour of the protein dispersions, while the turbidity of C-MPC dispersions decreased with increasing SHMP addition.

Serum protein concentrates (SPCs) were generated from reconstituted skim milk (3.2% protein) using lab-scale tangential-flow filtration at 3–4 °C. The influence of membrane type on process performance (e.g., permeate flux) and protein-enrichment (e.g., protein profile) was assessed with polyvinylidene-difluoride membranes (0.1 μm and 0.45 μm pore-size), and a polyethersulfone membrane (1000 kDa cut-off). The 1000 kDa membrane exhibited the highest starting flux (6.7 L m −2 h −1 ), followed by the 0.1 μm (5.4 L m −2 h −1 ) and 0.45 μm (4.8 L m −2 h −1 ) membranes. Flux decreased by >40% during filtration with the 1000 kDa and 0.1 μm membranes, while the decrease was lower ( 97% of casein in SPCs from the 0.1 μm and 1000 kDa membranes. SPCs from the 0.45 μm membrane had higher β-casein:α s -casein ratios than the feed and higher levels of minor whey proteins (e.g., lactoferrin) relative to the other SPCs.

This serological follow up study assessed the kinetics of antibody response in children who previously participated in a single centre, open-label, randomised controlled trial of low-dose compared to standard-dose diphtheria booster preschool vaccinations in the United Kingdom (UK). Children had previously been randomised to receive one of three combination vaccines: either a combined adsorbed tetanus, low-dose diphtheria, 5-component acellular pertussis and inactivated polio vaccine (IPV) (Tdap-IPV, Repevax(®); Sanofi Pasteur MSD); a combined adsorbed tetanus, low-dose diphtheria and 5-component acellular pertussis vaccine (Tdap, Covaxis(®); Sanofi Pasteur MSD) given concomitantly with oral polio vaccine (OPV); or a combined adsorbed standard-dose diphtheria, tetanus, 2-component acellular pertussis and IPV (DTap-IPV, Tetravac(®); Sanofi Pasteur MSD). Blood samples for the follow-up study were taken at 1, 3 and 5 years after participation in the original trial (median, 5.07 years of age at year 1), and antibody persistence to each vaccine antigen measured against defined serological thresholds of protection. All participants had evidence of immunity to diphtheria with antitoxin concentrations greater than 0.01IU/mL five years after booster vaccination and 75%, 67% and 79% of children who received Tdap-IPV, Tdap+OPV and DTap-IPV, respectively, had protective antitoxin levels greater than 0.1IU/mL. Long lasting protective immune responses to tetanus and polio antigens were also observed in all groups, though polio responses were lower in the sera of those who received OPV. Low-dose diphtheria vaccines provided comparable protection to the standard-dose vaccine and are suitable for use for pre-school booster vaccination.

• The extent and characteristics of influenza outbreaks in three primary schools have been described.

The aim of this study was to determine the effects of ultrasound on the dissolution properties of milk protein concentrate (MPC) powders. A high intensity ultrasound (20 kHz; power 70.2 W) was used to dissolve MPC powder and the dissolution rate was compared to conventional methods of dispersion (e.g., stirring). Rehydration of MPC by stirring at 50 °C complied with the 2-step dissolution model whereby the disappearance of larger particles coincided with the formation of smaller ones over time. MPC dispersal by sonication dramatically accelerated this process, achieving >90% levels of powder solubilisation. Temperature rise (>70 °C) during sonication causes protein denaturation and aggregation, but this can be alleviated using thermal dissipation. Overall, the use of a combination rehydration process for MPC powders involving (i) conventional dissolution (stirring) for 10 min at 50 °C followed by (ii) ultrasonication (

Lactoferrin and β-casein represent a large proportion of the proteins in human milk and, as a result, are important ingredients for the manufacture of infant formula. At pH 7, lactoferrin has a net positive charge, compared to the negatively charged β-casein. The effects of CaCl 2 and heat treatment on the stability of oil-in-water emulsions stabilised by lactoferrin and/or β-casein were investigated. The ζ-potential values of emulsions stabilised with β-casein or a 1:1 mixture of β-casein/lactoferrin significantly ( P 2 , while CaCl 2 had no significant ( P > 0.05) effect on the ζ-potential of lactoferrin-stabilised emulsions. Particle size of β-casein-stabilised emulsions increased significantly ( P 2 , due to flocculation, while emulsions stabilised with lactoferrin and β-casein/lactoferrin remained unaffected by CaCl 2 addition. Oscillatory rheology measurements showed that β-casein-stabilised emulsions formed a gel when CaCl 2 was added, due to calcium-bridging, compared to lactoferrin-stabilised emulsions, where a weaker gel was formed in the presence of CaCl 2 . While, 30 mM CaCl 2 did not increase the elastic modulus ( G ′) of β-casein/lactoferrin-stabilised emulsions. Lactoferrin protected β-casein from calcium-induced flocculation by: (1) binding calcium ions via sialic acid groups on lactoferrin molecules and reducing the number of free ions available to form calcium linkages between β-casein molecules; (2) electrostatically interacting with negatively charged phosphate groups on β-casein molecules, blocking calcium–phosphate interactions and (3) providing additional stability through increased steric repulsion between β-casein/lactoferrin conjugates, due to the large molecular size of lactoferrin.

Bovine β-casein was purified from phosphocasein by rennet coagulation and cold solubilisation from the resultant curd. β-Casein was then dephosphorylated using potato acid phosphatase. Urea-polyacrylamide gel electrophoresis (PAGE) of partially dephosphorylated β-casein showed a number of bands, depending on the final level of phosphorylation. Dephosphorylating β-casein increased its pH of minimum solubility from ∼pH 5 to 5.5 and reduced its net negative charge from −30.8 to −27.0 mV. During the acidification of β-casein solutions, partially dephosphorylated β-casein failed to form a gel, unlike the phosphorylated (i.e., control) β-casein. Use of partially dephosphorylated β-casein to stabilise oil-in-water emulsions resulted in larger fat globules compared to control β-casein, but such globules were less susceptible to aggregation in the presence of 15 or 30 mM CaCl 2 . Overall, the dephosphorylation of β-casein resulted in a protein similar to human β-casein in terms of physicochemical functionality, with increased stability against calcium-induced aggregation.

The objective of this study was to examine the effects of lowering protein content of a model infant formula on its processing characteristics and physical stability. Formulations containing five different protein:fat ratios (0.21–0.43) were investigated. Increasing protein:fat ratio increased viscosity and decreased fat globule size. Fat globule size increased significantly upon evaporation ( P P τ ) did not differ significantly between treatments. Increasing protein:fat ratio resulted in decreased creaming rates and improved emulsion stability. In conclusion, decreasing the protein:fat ratio of the formulae, particularly to 0.21, reduced the physical stability of the emulsions.

Seventy-four patients were included in a double-blind, randomized, controlled trial comparing the analgesic efficacy and adverse effects of hydromorphone and morphine delivered by continuous subcutaneous infusion. Patients completed the Memorial Pain Assessment Card and a checklist of opioid-related adverse effects immediately before commencing subcutaneous infusion and 24, 48, and 72 hours later. An assessment tool was developed for the 60 patients who were too ill to complete their own questionnaire. The tool demonstrated excellent inter-rater reliability. Thirty-four percent of patients in the hydromorphone group and 27% of those in the morphine group died before completion of the study (P = 0.66). The hydromorphone group required more analgesia for breakthrough pain in the first 24 hours of the study (P = 0.03) and had a greater improvement in the behavior of frowning on movement and the comfort visual analogue scale (P = 0.08) over the course of the study. Adverse effects were rare and similar in both groups. This study found hydromorphone to be at least as effective as morphine when delivered by continuous subcutaneous infusion.

Mark Achtman devised the acronym YATM for “yet another typing method” when assessing the huge growth in the number of approaches to classifying different microbe strains. This increase was triggered by both new technologies and by the tendency for new typing schemes to be developed for each new question. Achtman concluded that the contribution of these fragmented activities to scientific progress was low. By contrast, the scope for convergence of complementary disciplines, such as microbial evolution and epidemiology, has been described along with the capacity for this convergence to support basic scientific progress and its translation into public health benefits.