Structural and physical-chemical properties of milk fat globules fractionated by a series of silicon carbide membranes.

Driven by the acknowledged health and functional properties of milk fat globules (MFGs), there is a growing interest to develop gentle methodologies for separation of fat from milk. In this study, separation of fat from raw milk and fractionation in streams containing MFGs of different size was achieved using a series of two silicon carbide ceramic membranes. A first step consisting of a 1.4 µm membrane aimed to concentrate the bulk of the fat, i.e. the larger MFGs (D[4,3] âˆ¼ 4 µm) followed by a 0.5 µm fractionation aimed to concentrate the residual milk fat in the permeate, i.e. fraction with the smaller MFGs (D[4,3] âˆ¼ 1.8-2.4 µm. The fat separation performance showed a yield of 92 % for the 1.4 µm membrane and 97 % for the 0.5 µm membrane. Both fat enriched retentates showed, by the confocal laser scanning microscopy, intact MFGs with limited damage in the MFG membrane. The fatty acid profile analysis and SAXS showed minor differences in fat acid composition and the crystallization behavior was related to differences in the fat content. The 0.5 µm permeate containing the smallest MFGs however showed larger aggregates and a trinomial particle size distribution, due to probably pore pressure induced coalescences. The series of silicon carbide membranes showed potential to concentrate some of MFGM proteins such as Periodic Schiff base 3/4 and cluster of differentiation 36 especially in the 0.5 µm retentates. A shift in casein to whey protein ratio from 80:20 (milk) to 50:50 was obtained in the final 0.5 µm permeate, which opens new opportunities for product development.

Modelling of dynamic mastication physics of cheese/casein gels as function of milk-fat distribution and intensity of thermo-mechanical treatment.

Pasta filata-style cheese products are among the world's most famous cheese varieties. Thermo-mechanical processing of cheese curd results in stringy, fibrous, and anisotropic structures with pleasing texture attributes. A recent area of research focuses on improving yield during the manufacturing of pasta filata-type cheese products by homogenizing the milk. This process reduces the size of fat droplets, leading to better retention of milk fat during curd plasticization. As this sometimes results in texture deficits, this study aims to investigate the impact of thermo-mechanical processing on curd from homogenized and non-homogenized milk. The hypothesis is that increased thermo-mechanical processing, leading to more anisotropic structural elements, may offset texture deficits caused by homogenization. To assess textural and structural changes due to homogenization and thermo-mechanical processing, mechanical tests including rheology and texture analysis were conducted, along with confocal-laser-scanning microscopy. Additionally, sensory evaluation involving panelists consuming the samples and recording mastication properties such as muscle activity and jaw movement was carried out. Dynamic data modeling was used to derive connections between structure and texture. Results showed that homogenization alone did not yield significant differences between the samples, but plasticization and texturization properties differed significantly. Non-homogenized samples developed a distinct fibrous structure, and muscle activities and jaw movements increased significantly (p < 0.01) with longer thermo-mechanical processing.

Gestational Diabetes Mellitus-Induced Milk Fat Globule Membrane Protein Changes of Human Mature Milk Based on TMT Proteomic Analysis.

Breastfeeding by mothers with gestational diabetes mellitus (GDM) has been shown to reduce maternal insulin demands and diminish the risks of diabetes in infants, leading to improved long-term health outcomes. Milk fat globule membrane (MFGM) proteins play a crucial role in influencing the immunity and cognitive development of infants. Understanding the alterations in MFGM proteins in breastmilk from mothers with GDM is essential for enhancing their self-efficacy and increase breastfeeding rates. The objective of this study is to investigate and compare MFGM proteins in milk from mothers with GDM and without based on tandem mass tag (TMT) labeling and liquid chromatography tandem mass spectrometry (LC-MS) techniques. A total of 5402 proteins were identified, including 4 upregulated proteins and 24 downregulated proteins. These significantly altered proteins were found to be associated with human diseases, cellular processes, and metabolism pathways. Additionally, the oxidative phosphorylation pathway emerged as the predominant pathway through Gene Set Enrichment Analysis (GSEA) involving all genes.

Effects of betaine supplementation on dry matter intake, milk characteristics, plasma non-esterified fatty acids, and beta-hydroxybutyric acid in dairy cattle: a meta-analysis.

Betaine supplementation in dairy cattle has gained attention due to its potential benefits to production and health as a methyl donor, which can play a crucial role in the metabolism of dairy cows. The objective of the current meta-analysis was to quantify the effects of betaine supplementation on milk production, composition, beta-hydroxybutyric acid (BHBA), and non-esterified fatty acids (NEFA). A systematic literature search was carried out, all relevant studies were retrieved, and the meta-analysis was carried out. The mean difference (MD) for dry matter intake (DMI) using the random-effects model was 0.499 kg/day (P < 0.0001). The subgroup analysis indicated that supplementing betaine in heat-stressed cows increased DMI by 0.584 kg/day (P < 0.001), while in cows not exposed to heat stress, DMI was increased by 0.381 kg/day (P = 0.007). The energy-corrected milk (ECM) increased by 1.36 kg/day (P < 0.0001). The milk fat yield was significantly increased in betaine-supplemented cows (MD = 0.040 kg/day, 95% CI = 0.015 to 0.065). The milk protein yield (kg/day) (MD = 0.014, P = 0.138) was increased (MD = 0.035, P = 0.0005) by betaine supplementation. The lactose yield (kg/day) was also significantly higher (MD = 0.055, P = 0.020) in betaine-supplemented cows. The standardized mean difference (SMD) for NEFA (SMD = -0.447, 95% CI = -1.029 to 0.135, P = 0.114) and BHBA (SMD = -0.130, 95% CI = -0.491 to 0.234). In conclusion, the findings from this meta-analysis suggest that betaine supplementation positively influences DMI, ECM, milk fat yield, milk lactose yield, and milk protein yield. Subgroup analysis further indicated that the positive effects on DMI are greater in heat-stressed cows compared to those not exposed to heat stress. The analysis did not find significant effects on the levels of NEFA or BHBA, suggesting that betaine supplementation may not directly influence these metabolic parameters.

L-leucine promotes the synthesis of milk protein and milk fat in bovine mammary epithelial cells through the AKT/mTOR signaling pathway under hypoxic conditions.

Hypoxia stress has been demonstrated to impede animal embryonic development, spermatogenesis, and lactation, leading to decreased animal production performance. However, the impact of hypoxia-induced activation of hypoxia inducible factor-1 (HIF-1) signaling on milk protein and fat synthesis remains unclear. L-leucine, a branched-chain amino acid, is known to modulate milk protein and fat synthesis. Therefore, our study aimed to evaluate the effect of L-leucine on milk protein and fat synthesis under hypoxic conditions and shed light on the molecular mechanism using an in vitro model. The results indicated that hypoxia treatment significantly decreased the synthesis of α-casein and ß-casein, as well as inhibited factors related to milk fat synthesis in bovine mammary epithelial cells (MAC-T). Additionally, hypoxia stress suppressed the activities of the mammalian target of rapamycin (mTOR) and protein kinase B (AKT). Interfering with HIF-1α significantly reversed the expression of AKT, mTOR and factors related to milk synthesis. Importantly, supplementation with L-leucine activated AKT/mTOR signaling, thereby enhancing milk protein and fat synthesis in MAC-T cells to some extent. In conclusion, these findings suggest that HIF-1 signaling plays an important role in milk synthesis and that L-leucine may stimulate the synthesis of milk protein and fat by activating the AKT/mTOR signaling pathway under hypoxic conditions, making it a potential additive for promoting milk synthesis inhibited by hypoxia.

Comprehensive review of milk fat globule membrane proteins across mammals and lactation periods in health and disease.

Milk fat globule membrane (MFGM) is a three-layer membrane-like structure encasing natural milk fat globules (MFGs). MFGM holds promise as a nutritional supplement because of the numerous physiological functions of its constituent protein. This review summarizes and compares the differences in MFGM protein composition across various species, including bovines, goats, camels, mares, and donkeys, and different lactation periods, such as colostrum and mature milk, as assessed by techniques such as proteomics and mass spectrometry. We also discuss the health benefits of MFGM proteins throughout life. MFGM proteins promote intestinal development, neurodevelopment, and glucose and lipid metabolism by upregulating tight junction protein expression, brain function-related genes, and glucose and fatty acid biosynthesis processes. We focus on the mechanisms underlying these beneficial effects of MFGM proteins. MFGM proteins activate key substances in in signaling pathways, such as the phosphatidylinositol 3-kinase/protein kinase B, mitogen-activated protein kinase, and myosin light chain kinase signaling pathways. Overall, the consumption of MFGM proteins plays an essential role in conferring health benefits, some of which are important throughout the mammalian life cycle.

Types and amounts of MFGM proteins in mammals, as assessed by proteomic and mass spectrometry analysis, are summarized.Colostrum MFGM contains more acute phase proteins, whereas mature milk has higher levels of mucins (1 and 15), ADPH, XDH, and FABP.Health benefits of MFGM proteins, including intestinal development, neurodevelopment, and immune activity enhancement, are summarized.MFGM proteins have been shown to significantly activate the PI3K/Akt/mTOR signaling pathway, promoting cell proliferation and glycolipid metabolism.

Full-fat dairy products and cardiometabolic health outcomes: Does the dairy-fat matrix matter?

Reducing dairy fat intake is a common dietary guideline to limit energy and saturated fatty acid intake for the promotion of cardiometabolic health. However, research utilizing a holistic, food-based approach to assess the consumption of the fat found in dairy, a broad and diverse food group, may provide new insight into these guidelines. Dairy fat is comprised of a diverse assembly of fatty acids, triacylglycerols, sterols, and phospholipids, all uniquely packaged in a milk fat globule. The physical structure of this milk fat globule and its membrane is modified through different processing methods, resulting in distinctive dairy-fat matrices across each dairy product. The objectives of this narrative review were to first define and compare the dairy-fat matrix in terms of its unique composition, physical structure, and fat content across common dairy products (cow's milk, yogurt, cheese, and butter). With this information, we examined observational studies and randomized controlled trials published within the last 10 years (2013-2023) to assess the individual effects of the dairy-fat matrix in milk, yogurt, cheese, and butter on cardiometabolic health and evaluate the implications for nutrition guidance. Searches conducted on Ovid MEDLINE and PubMed® utilizing search terms for cardiometabolic health, both broadly and regarding specific disease outcomes and risk factors, yielded 59 studies that were analyzed and included in this review. Importantly, this review stratifies by both dairy product and fat content. Though the results were heterogeneous, most studies reported no association between intake of these individual regular-fat dairy products and cardiometabolic outcome measures, thus, the current body of evidence suggests that regular-fat dairy product consumption may be incorporated within overall healthy eating patterns. Research suggests that there may be a beneficial effect of regular-fat milk and yogurt intake on outcome measures related to body weight and composition, and an effect of regular-fat cheese intake on outcome measures related to blood lipids, but more research is necessary to define the directionality of this relationship. Lastly, we identify methodological research gaps and propose future research directions to bolster the current evidence base available for ascertaining the role of dairy fat in a healthy diet.

The Effects of Two Selected Single Nucleotide Polymorphisms of the Fatty Acid Synthase Gene on the Fat Content and Fatty Acid Profile of Cow's Milk from the Polish Holstein-Friesian Red-and-White Breed versus Two Polish Red-and-White and Polish Red Conservation Breeds Kept in Poland.

Fatty acid synthase (FASN) is a metabolic enzyme responsible for the synthesis of fatty acids in milk and meat. The SNPs g.841G/C and g.17924A/G of the FASN gene significantly influence the fat and fatty acid content of milk from cows of various breeds. Therefore, these SNPs were selected for this study. This study aimed to analyze the relationship of SNPs and their genotypes with the fat content and fatty acid profile of milk from Polish Red-and-White (ZR), Polish Red (RP), and Polish Holstein-Friesian Red-and-White (RW) cows. Milk samples were obtained during a milking trial. SNP genotyping was performed using the real-time PCR (HRM) method. It was shown that SNPs (with specific genotypes) were significantly associated with the presence of fatty acids such as C18:1n9t and C18:2n6c in milk. In addition, it was found that the milk fat from the ZR (genotypic variant A/G, AA) and RP (genotypic variant GG, A/G) breeds often exhibited a more attractive fatty acids profile than the milk fat from RW cows. This information can be used by both cattle breeders and people interested in consuming functional foods.

Mammary gland responses to altering the supply of de novo fatty acid substrates and preformed fatty acids on the yields of milk components and milk fatty acids.

The objective of our study was to evaluate the effect of altering the dietary supply of acetate, palmitic acid (PA), and cottonseed on the yields of milk components and milk fatty acids (FA) in lactating dairy cows. Thirty-two multiparous Holstein cows (133 ± 57 d in milk, 50.5 ± 7.2 kg/d milk) were used in a 4 × 4 Latin square split plot design with a 2 × 2 factorial arrangement of subplot treatments. Cows were blocked by energy-corrected milk (ECM) yield and allocated to a main plot receiving a basal diet (n = 16) with no supplemental PA (Low PA) or a basal diet (n = 16) with 1.5% inclusion of a FA supplement containing ~85% PA (High PA). In each main plot, the following subplots of treatment diets were fed in a Latin square arrangement consisting of 14-d periods: 1) a control diet (CON), 2) the control diet supplemented with 3% sodium acetate (AC), 3) the control diet supplemented with 12% whole cottonseed (CS), and 4) the control diet supplemented with 3% sodium acetate and 12% whole cottonseed (CS+AC). The PA supplement and sodium acetate replaced soyhulls, and whole cottonseed replaced cottonseed hulls and meal. All diets were balanced for 30% neutral detergent fiber (NDF), 23% forage NDF, 28% starch, and 17% crude protein (CP). Sources of FA were classified as de novo (<16 carbons), mixed (16-carbon), and preformed (>16 carbons). The statistical model included the random effect of cow nested within basal diet and fixed effect of period, basal diet, acetate, cottonseed, and their interactions. Three-way interactions among basal diet, acetate, and cottonseed were observed for the yields of milk fat, 3.5% fat-corrected milk (FCM), and the molar yields of de novo FA, mixed FA, and preformed FA. In the Low PA diets, AC and CS+AC increased the yields of milk fat and FCM compared with CON and CS, whereas, in the High PA diets, CS+AC increased the yields of milk fat and FCM compared with the other treatments and AC increased milk fat yield compared with CON and CS. Compared with Low PA, High PA increased milk fat content, mixed FA yield, and tended to increase C4:0 yield. Diets containing acetate increased DMI and the yields of milk fat, ECM, FCM, de novo FA, mixed FA, and preformed FA compared with diets without acetate. Diets containing cottonseed increased the yields of milk and preformed FA, tended to increase the yields of FCM and protein, and decreased DMI and the yields of de novo FA and mixed FA compared with diets without cottonseed. In summary, in high PA diets, the inclusion of acetate plus cottonseed increased milk fat yield compared with the other treatments. The CON diet in High PA increased milk fat yield to the same extent as AC and CS+AC in Low PA suggesting PA is important for initiating milk TG synthesis. Balancing the supply of de novo FA substrates and preformed FA is important for increasing the synthesis of milk fat triglycerides and milk fat production.

Effect of temperature on the rheological, textural, and sensory properties of butters from New Zealand market.

Texture and sensory studies at various temperatures are important in evaluating and improving the functionality of butter. While literature is scarce, we evaluated and compared the effect of temperature (5-25°C) on the texture, rheological and sensory properties of commercial butter samples (salted, unsalted, cultured, and spreadable) from the New Zealand market. In addition, the instrumental analyses were compared with the sensory evaluation, to understand the possibility of using instrumental analysis to evaluate consumer liking for different butters. Butter type, temperature, and their type-temperature interaction exhibited significant differences for all instrumental textural parameters. As expected, higher temperature produced softer butter that was more spreadable, liquid-like, less adhesive, less cohesive, had lower storage modulus (G') and lower loss modulus (G″) with the melting of milk fat crystals; however, the rate of change varied for the different butter samples. We have established meltability as the parameter for evaluating butter selection for different applications. The spreadable butter sample exhibited the lowest hardness and G', and highest spreadability (p < .05) at all temperatures, owing to its low solid fat content and the abundance of low-melting triglycerides. The cultured butter sample had the highest melting point, owing to compositional differences. The instrumental and sensory texture analyses were highly correlated, indicating the comparative effectiveness of both approaches for studying the effects of different temperatures on butter textural properties. Overall, our findings provide detailed reference to the dairy industry for butter manufacture, considering variation in fatty acid composition, texture analysis, rheology, and sensory analysis, over the range of storage/usage temperatures.

Bta-miR-200a Regulates Milk Fat Biosynthesis by Targeting IRS2 to Inhibit the PI3K/Akt Signal Pathway in Bovine Mammary Epithelial Cells.

Milk fat synthesis has garnered significant attention due to its influence on the quality of milk. Recently, an increasing amount of proofs have elucidated that microRNAs (miRNAs) are important post-transcriptional factor involved in regulating gene expression and play a significant role in milk fat synthesis. MiR-200a was differentially expressed in the mammary gland tissue of dairy cows during different lactation periods, which indicated that miR-200a was a candidate miRNA involved in regulating milk fat synthesis. In our research, we investigated the potential function of miR-200a in regulating milk fat biosynthesis in bovine mammary epithelial cells (BMECs). We discovered that miR-200a inhibited cellular triacylglycerol (TAG) synthesis and suppressed lipid droplet formation; at the same time, miR-200a overexpression suppressed the mRNA and protein expression of milk fat metabolism-related genes, such as fatty acid synthase (FASN), peroxisome proliferator-activated receptor gamma (PPARγ), sterol regulatory element-binding protein 1 (SREBP1), CCAAT enhancer binding protein alpha (CEBPα), etc. However, knocking down miR-200a displayed the opposite results. We uncovered that insulin receptor substrate 2 (IRS2) was a candidate target gene of miR-200a through the bioinformatics online program TargetScan. Subsequently, it was confirmed that miR-200a directly targeted the 3'-untranslated region (3'-UTR) of IRS2 via real-time fluorescence quantitative PCR (RT-qPCR), western blot analysis, and dual-luciferase reporter gene assay. Additionally, IRS2 knockdown in BMECs has similar effects to miR-200a overexpression. Our research set up the mechanism by which miR-200a interacted with IRS2 and discovered that miR-200a targeted IRS2 and modulated the activity of the PI3K/Akt signaling pathway, thereby taking part in regulating milk fat synthesis in BMECs. Our research results provided valuable information on the molecular mechanisms for enhancing milk quality from the view of miRNA-mRNA regulatory networks.

Milk Fat Globule-EGF Factor 8 (MFGE8) Mitigates Cognitive Impairment in Rats with Sepsis-Associated Encephalopathy: An fMRI Study.

BACKGROUND: Sepsis-associated encephalopathy (SAE) impairs hippocampal microglial efferocytosis, causing cognitive deficits. Previous research found that milk fat globule epidermal growth factor 8 protein (MFGE8) stimulates efferocytosis, reducing hippocampal inflammation in SAE rats. In this study, we explore MFGE8's role in alleviating cognitive impairment and its impact on neural activity using functional magnetic resonance imaging (fMRI). METHODS: Sixty male Sprague Dawley rats were divided into four groups: Sham, cecal ligation and puncture (CLP), CLP+MFGE8, and CLP+MFGE8+CGT (Cilengitide). After CLP, CLP+MFGE8 rats received intracerebroventricular MFGE8 (3.3 µg), while CLP+MFGE8+CGT rats received intraperitoneal Cilengitide (10 mg/kg). We assessed cognitive function with the Morris water maze and open field test over five days. Eight days post-surgery, rats underwent T2-weighted magnetic resonance imaging (MRI) and resting state (rs)-fMRI scans. Brain tissues were collected for western blot, hematoxylin-eosin (HE) staining, and immunofluorescence. Statistical analysis employed one-way analysis of variance (ANOVA) followed by Tukey's post-test for multiple comparisons. RESULTS: MFGE8 improved neurobehavioral performance in open field task (OFT) and morris water maze (MWM) tests. fMRI indicated a significant reduction in abnormal neural activity in the right hippocampal CA1, CA3, and dentate gyrus of SAE rats following MFGE8 treatment. Voxel-based morphometry (VBM) analysis revealed decreased high-signal areas in the hippocampus, along with reduced hippocampal volume due to alleviated neural edema. Western blot analysis demonstrated that MFGE8 enhanced ras-related C3 botulinum toxin substrate 1 (Rac1) and microtubule-associated protein 1A/1B-light chain 3 (LC3) expression in the rat hippocampus, while CGT reduced these protein levels. Behavioral experiments and fMRI results confirmed that CGT reversed the cognitive effects of MFGE8 by inhibiting microglial αVß3/αVß5 integrin receptors. CONCLUSIONS: Our findings show that MFGE8 reduced amplitude of low-frequency fluctuations (ALFF) values in the right hippocampal CA1, CA3, and the dentate gyrus, mitigating abnormal neural activity and decreasing hippocampal volume. This led to an improvement in cognitive dysfunction in SAE rats. These results suggest that MFGE8 enhances microglial efferocytosis by activating αVß3 and αVß5 integrin receptors on microglial surfaces, ultimately improving cognitive function in SAE rats.

Multispecies pasture diet and cow breed impacts on milk composition and quality in a seasonal spring-calving dairy production system.

In recent years, there has been significant emphasis on the composition of pasture-based cow feed and the potential benefits of incorporating multispecies swards to improve sustainability and biodiversity. This study compared the effects of a conventional perennial ryegrass (PRG) monoculture supported by high chemical nitrogen (N) usage with a low chemical N application multispecies sward system (MSS) on the composition and quality of milk across lactation using spring-calving Holstein-Friesian (HF) and Jersey Holstein-Friesian (JFX) cows. Bulk milk samples (n = 144) were collected from each group at morning and evening milking on a weekly basis (n = 36) throughout lactation and analyzed for gross composition and physico-chemical properties. Cow breed had a significant impact on milk profile, with milk from HF cows having significantly smaller milk fat globule (MFG) size, higher instability index values, higher yield, and lower total solids levels, compared with JFX cows. Notably, HF cows had increased milk total solids and fat levels when fed on MSS, as opposed to the PRG-fed HF cows. Feeding MSS pasture increased creaming velocity values in mid and late lactation, and resulted in similar milk gross composition to PRG. In comparison to PRG, MSS-fed groups showed significantly increased total solids yield, including higher levels of protein and fat yield. In late lactation, MSS feeding was associated with reduced MFG size. All physicochemical properties studied (MFG size, creaming velocity, instability index) showed decreasing values from early to late lactation stage. Overall, these findings demonstrate the significant effects of cow diet, breed and stage of lactation on compositional and physico-chemical characteristics of milk, with important implications for milk processing and dairy product quality.

Milk Fat Globule Membrane-Containing Protein Powder Promotes Fitness in Caenorhabditis elegans.

Milk-derived peptides and milk fat globule membrane (MFGM) have gained interest as health-promoting food ingredients. However, the mechanisms by which these nutraceuticals modulate the function of biological systems often remain unclear. We utilized Caenorhabditis elegans to elucidate how MFGM-containing protein powder (MProPow), previously used in a clinical trial, affect the physiology of this model organism. Our results demonstrate that MProPow does not affect lifespan but promotes the fitness of the animals. Surprisingly, gene expression analysis revealed that MProPow decreases the expression of genes functioning on innate immunity, which also translates into reduced survival on pathogenic bacteria. One of the innate immunity-associated genes showing reduced expression upon MProPow supplementation is cpr-3, the homolog of human cathepsin B. Interestingly, knockdown of cpr-3 enhances fitness, but not in MProPow-treated animals, suggesting that MProPow contributes to fitness by downregulating the expression of this gene. In summary, this research highlights the value of C. elegans in testing the biological activity of food supplements and nutraceuticals. Furthermore, this study should encourage investigations into whether milk-derived peptides and MFGM mediate their beneficial effects through the modulation of cathepsin B expression in humans.

Bovine Milk Fat Globule Membrane Supplementation and Neurocognitive Development: A Systematic Review and Meta-Analysis.

Given the limited evidence, there is no conclusive proof of the neurocognitive benefits of bovine milk fat globule membrane supplementation in infant formula. This study evaluates the neurocognitive benefits of bovine milk fat globule membrane supplementation in formula, comparing it to standard formula and assessing its noninferiority to breast milk. Data were sourced from studies published between January 2000 and March 2024 from PubMed, Cochrane Library, Web of Science, and Embase. Eight randomized controlled trials involving 1352 healthy term neonates, infants, and children up to 2 years old were included. Bovine milk fat globule membrane supplementation was significantly associated with improved cognitive development (mean difference: 3.29, 95% CI: 1.65 to 4.93, p < 0.001) and demonstrated minimal heterogeneity (I2 = 0%, p = 0.564). It showed significant improvement in executive function but not in language, motor, or social-emotional development. In non-inferiority analysis, there was no significant difference compared to breast milk regarding cognitive development. These findings support bovine milk fat globule membrane as a valuable addition to infant formula for cognitive benefits.

Human milk fat substitutes rich in 1,3-dioleoyl-2-palmitoylglycerol and 1-oleoyl-2-palmitoyl-3-linoleoylglycerol simultaneously: Preparation strategy and simulated infant in vitro digestion.

In this study, fractionated palm stearin, oleic acid, and linoleic acid were selected as the base materials to prepare human milk fat substitutes (HMFS) rich in OPO and OPL by enzymatic acidolysis combined with physical blending. Under optimum conditions, contents of OPO, OPL, and sn-2 palmitic acid in the OPO and OPL-rich triacylglycerols (TAGs) were higher than that in commercial OPO-rich TAGs, with values of 37.25%, 28.12%, and 79.44%, respectively. Physical blending the OPO and OPL-rich TAGs (47%), bovine milk fat (18%), sunflower oil (13%), coconut oil (13%), corn oil (8%), and palm oil (1%) can obtain HMFS with a fat composition that like HMF. The fatty acid, sn-2 saturated fatty acid, and TAG contents of HMFS were within the lower and upper limit of HMF. The lipolysis degree of infant formula (IF) with HMFS as fat source is 9.0% higher than that of commercial plant oil-based infant formula (PIF), and 3.4% lower than that of human milk. IF with HMFS as fat source released less saturated free fatty acids and more saturated monoacylglycerols during digestion than that of PIF, which would help improve the IF fat utilization by infants.

Application of in-line Raman spectroscopy to monitor crystallization and melting processes in milk fat.

Anhydrous milk fat (AMF) and its fractions are used as ingredients in a wide range of food applications. Obtaining the appropriate solid fat content (SFC) is essential to achieve the desired product texture. At present, in-line monitoring techniques to control milk fat crystallization and melting are largely unavailable. The thermal behaviour of milk fat (AMF and four of its fractions) was monitored in a temperature-controlled vessel using an in-line Raman analyser and compared with thermograms generated using differential scanning calorimetry (DSC). The major stages of milk fat crystallization and melting were identified using the in-line Raman analyser. Thermal data from DSC showed excellent linear correlations with Raman spectral data (R2 value of 0.97 for the onset of milk fat crystallisation). Partial least squares regression (PLSR) models were developed using Raman spectra to predict SFC with coefficient of determination (R2Cs) from 0.929 to 0.992 and root mean standard error of calibration (RMSECs) ranging from 3.20 to 10.36%. Results demonstrated Raman spectroscopy has significant potential as a way of monitoring milk fat crystallization and melting processes.

Subacute Rumen Acidosis in Greek Dairy Sheep: Prevalence, Impact and Colorimetry Management.

Subacute rumen acidosis (SARA) is a current issue in intensive livestock farming, and it is particularly associated with feeding high-concentrate diets. This study investigated the prevalence and impact of SARA in forty-two Greek dairy sheep flocks by recording rumen pH, milk composition, and milk yield over a period of nine months. Moreover, it explored the use of computerized rumen colorimetry as a management and diagnostic tool for SARA in dairy sheep. In culled ewes, computerized rumen mucosal colorimetry was applied, and rumen wall samples taken for histological examination. SARA cases were identified in 19 farms (45%, n = 42). Farms with SARA cases had lower milk fat levels, while milk yield and milk protein levels did not differ based on the SARA status of the farms. In culled ewes, rumen color was significantly associated with the flock's SARA status, and affected ewes showed increased thickness in non-keratinized and total epithelial layers. It was concluded that computerized rumen mucosal colorimetry in aged, culled ewes shows promise as an indicator, post mortem, of SARA present in dairy sheep flocks whose impact can be minimized by making significant changes in dietary management.

Isolation and Characterization of Milk Exosomes for Use in Advanced Therapies.

Exosomes are cell-derived extracellular vesicles (EVs) with diameters between 30 and 120 nm. In recent years, several studies have evaluated the therapeutic potential of exosomes derived from different fluids due to their low immunogenicity and high biocompatibility. However, producing exosomes on a large scale is still challenging. One of the fluids from which they could be isolated in large quantities is milk. Moreover, regeneration is a well-known property of milk. The present work seeks to optimize a method for isolating exosomes from bovine and human milk, comparing different storage conditions and different extraction protocols. We found differences in the yield extraction associated with pre-storage milk conditions and observed some differences according to the processing agent. When we removed milk fat globules and added rennet before freezing, we obtained a cleaner final fraction. In summary, we attempted to optimize a rennet-based new milk-exosome isolation method and concluded that pre-treatment, followed by freezing of samples, yielded the best exosome population.

Differences in proteomic profiles and immunomodulatory activity of goat and cow milk fat globule membrane.

This study aimed to clarify the composition and bioactivity differences between goat and cow milk fat globule membrane (MFGM) protein by proteomic, and the immunomodulatory activity of MFGM proteins was further evaluated by using mouse splenic lymphocytes in vitro. A total of 257 MFGM proteins showed significant differences between goat and cow milk. The upregulated and unique MFGM proteins in goat milk were significantly enriched in the positive regulation of immune response, negative regulation of Interleukin-5 (IL-5) secretion, and involved in nucleotide-binding oligomerization domain (NOD)-like receptor signaling. The contents of IL-2 and Interferon-γ in the supernatant of spleen lymphocytes treated with goat MFGM proteins were much higher than those of IL-4 and IL-5, suggesting a Th1-skewed immune response. These results revealed that goat MFGM proteins could possess better immunomodulatory effects as compared to cow milk. Our findings may provide new insights to elucidate the physiological functions and nutritional of goat milk.