Search Results (205)

With the growing interest in pandan-based products, bitterness and astringency associated with flavonoids may limit their sensory acceptance. This study investigated the interactions and taste-modulating effects of two milk proteins, β-casein (β-CN) and β-lactoglobulin (β-LG), with two representative bitter flavonoids, catechin (C) and naringin (NAR), in aqueous model systems. Fluorescence spectroscopy showed that both flavonoids produced concentration-dependent quenching of the milk proteins. β-CN exhibited more pronounced interaction-related spectroscopic responses than β-LG, which may be associated with its flexible and intrinsically disordered structure. Molecular docking predicted hydrogen-bonding and hydrophobic interactions in all four protein–flavonoid systems, with catechin and naringin interacting mainly with the internal hydrophobic cavity of β-LG and surface-exposed regions of the β-CN model. Circular dichroism and Fourier-transform infrared spectroscopy indicated ligand-dependent structural changes. For β-LG, catechin slightly decreased the estimated antiparallel and total β-sheet fractions, whereas naringin produced a modest increase. For β-CN, catechin produced a more apparent redistribution between the estimated α-helix and β-sheet fractions, while naringin caused comparatively smaller changes. Electronic tongue measurements showed that the addition of the milk proteins reduced the bitterness- and astringency-related sensor responses of catechin and naringin. Under the tested conditions, β-CN produced greater attenuation of these responses than β-LG, while the umami-related response remained comparatively high. These findings support the potential application of milk proteins as taste-modulating components in flavonoid-containing dairy formulations, although validation in real food matrices is required. Full article

The β-casein gene (CSN2) encodes one of the major milk proteins involved in calcium and phosphorus transport and combines a highly conserved genomic organization with extensive genetic diversity, making it an informative model for investigating mammalian genome evolution. Although numerous studies have described CSN2 polymorphisms, particularly in domestic species, the broader evolutionary history of the locus remains poorly understood. Here, we investigated the evolutionary architecture of CSN2 across Bovidae and related Cetartiodactyla by integrating coding variation, non-coding polymorphisms, retroposon insertions and recombination analyses. Comparative genomic analyses identified previously undescribed caprine haplotypes, expanded the known spectrum of β-casein variation in domestic and wild Caprinae, and revealed multiple structural configurations of the locus, including distinct retroposon architectures and intronic insertion/deletion polymorphisms. Retroposon mapping and comparative analyses supported a hierarchical accumulation of structural variants, while also indicating ancestral polymorphism and lineage-specific retention in rapidly radiating caprine lineages. A locus-level phylogenetic analysis revealed two deeply divergent allelic lineages and provided evidence of ancient interallelic recombination predating the divergence of Capra and Ovis. Comparative analyses further showed that a two-amino-acid deletion previously associated mainly with Caprinae is more widely distributed across Bovidae than previously recognized. Overall, the CSN2 locus emerges as a multilayered evolutionary system shaped by structural variation, ancestral polymorphism, incomplete lineage sorting and ancient recombination, illustrating how the integration of coding, structural and retroposon variation can improve locus-level evolutionary reconstruction in Bovidae. Full article

Milk preservation requires technologies that extend shelf life while minimising undesirable changes in product quality. This study compared the effects of pasteurisation, sterilisation, and high hydrostatic pressure processing (HHP) on the physicochemical properties and protein profiles of raw whole bovine milk. The samples included untreated raw milk as the control, pasteurised milk (72 °C for 42 s), sterilised milk (121 °C for 15 min), and HHP-treated milk processed at 300, 400, 500, or 600 MPa for 5 min. Colour, pH, rheological behaviour, SDS-PAGE, and Native-PAGE were evaluated. Sterilisation caused the greatest total colour difference (ΔE* = 13.95), whereas pasteurisation resulted in a barely perceptible change (ΔE* = 0.64), and HHP-treated samples showed perceptible but lower colour differences (ΔE* = 3.42–3.97). Sterilisation also caused the most pronounced pH decrease and the highest shear stress values over most of the measured shear-rate range. SDS-PAGE profiles of raw and HHP-treated milk remained broadly similar, while Native-PAGE revealed pressure-dependent reductions in native β-lactoglobulin band intensity, particularly at 500 and 600 MPa. Pasteurisation and 600 MPa treatment reduced the κ-casein-associated band intensity by 54% and 58%, respectively. Overall, HHP induced less pronounced physicochemical and electrophoretic changes than sterilisation, although higher pressure levels caused measurable protein restructuring. Full article

Camel milk (CM), which is produced by both Camelus dromedarius and Camelus bactrianus, is gaining increasing popularity as a value-added functional dairy product, but the science of managing its shelf life has progressed more slowly than its commercial expansion. Unlike bovine milk, CM lacks β-lactoglobulin (β-LG), has a unique casein (CN) micelle structure with a high β-CN-to-αs1-CN ratio, and low κ-CN protein content, and contains an unusually rich bioactive protein fraction including lactoferrin (LF), immunoglobulin G (IgG), lysozyme (LZ), and peptidoglycan recognition protein (PGRP). These compositional characteristics imbue CM with both significant inherent antimicrobial benefits and place it at risk of processing weaknesses that do not have direct analogs in bovine dairy science. The review discusses three key areas of CM shelf life science that have not been sufficiently addressed in the published literature. The first relates to physicochemical mechanisms of deterioration, including lipid oxidation of polyunsaturated fatty acids (PUFA), destabilization of CN micelles in the structural absence of β-LG, and Maillard browning during thermal treatment and storage of powder. The second addresses the fate of bioactive proteins, with the majority being lactoferrin (LF), immunoglobulin G (Igs), and heavy chain-only antibodies (HCAbs), under both thermal and non-thermal processing conditions. The third looks at new non-thermal preservation methods, such as high-pressure processing (HPP), pulsed electric field (PEF), ultrasonication, ultraviolet irradiation, cold plasma, and electromagnetic (EM) field treatment, and functional packaging innovations, which contribute to longer shelf life. Of the non-thermal options examined, HPP at 200–400 MPa today provides the most mechanistically proven evidence for camel-specific microbial deactivation with satisfactory quality preservation. The latest primary CM research also indicates that processing with EMs in the 850 mT range can potentially be as effective as conventional pasteurization in microbial control and may be more effective than pasteurization in retaining desirable bioactive markers, although this result needs to be independently replicated before more responsible conclusions can be drawn. The review ends with four priority research gaps: standardized kinetic shelf life modeling frameworks, systematic characterization of bioactive protein stability under commercial processing conditions, life cycle assessment of preservation chains across the camel dairy supply continuum, and the urgent validation of camel-specific pasteurization adequacy indicators to replace bovine alkaline phosphatase, which remains active in CM after conventional high-temperature short-time (HTST) pasteurization. Full article

Cow’s milk allergy (CMA) is the most common food allergy in infants. Goat milk exhibits relatively low allergenicity and is widely regarded as a potential substitute for cow milk. However, the high sequence homology between cow and goat milk proteins may trigger cross-reactivity, significantly restricting the practical application of goat milk. This study aims to disrupt cross-linear epitopes of cow and goat milk proteins through enzymatic hydrolysis. We prepare hypoallergenic goat milk protein hydrolysates and systematically evaluate their desensitization effects. Bioinformatics methods were employed to predict the B-cell linear epitopes of six major allergens (α_S1-casein, α_S2-casein, β-casein, κ-casein, α-lactalbumin, and β-lactoglobulin) from cow, goat, and sheep milk, and sequence homology was analyzed through protein-protein Basic Local Alignment Search Tool (BLASTP). The results showed that the sequence similarity of homologous allergens among the three milk sources all exceeded 30%. Subsequently, six proteases (protamex, alcalase, pepsin, trypsin, papain and bromelain) were used to hydrolyze whole goat milk protein. Indirect enzyme-linked immunosorbent assay (ELISA) results indicated that all six hydrolysates significantly reduced immunoreactivity with antibodies against the five major cow’s milk allergens. Among them, alcalase exhibited significant efficacy against all five allergens; papain and protamex were particularly effective against β-casein; trypsin showed pronounced efficacy against α-lactalbumin and β-lactoglobulin; and bromelain and pepsin also significantly reduced immunoreactivity against certain allergens. Mass spectrometry revealed the peptide composition and epitope coverage of the hydrolysates: bromelain yielded two overlapping peptides (FAWPQY, LKDLKDY), protamex one (LAMAAS), Alcalase three (PPQSVLS, IPIQYVLS, LPYPYY), trypsin two (YLGYLEQL, AMAASDISLL), papain three (NEINQFYQK, FQSEEQQQTEDELQDK, AMAASDISL); and no matching peptide was detected for pepsin. These results confirmed at the molecular level that enzymatic hydrolysis can effectively disrupt cross-reactive epitopes. Full article

Interest in β-casein polymorphism and A2 milk production has increased considerably in recent years because of their potential effects on milk quality and dairy cattle breeding. The aim of this study was to determine the distribution of β-casein A1/A2 genotypes in Holstein-Friesian (HF) cattle and indigenous Busha cattle from Serbia and to evaluate the association between β-casein genotypes and milk production traits in HF cows. The study included 334 HF cows, 58 HF bulls, and 64 Busha cows. Genotyping was performed using the ACRS-PCR method, followed by restriction fragment analysis. Milk production data for HF cows included milk yield, milk protein content, and milk fat content during the first and second lactation. Statistical analysis included determination of genotype and allele frequencies, testing of Hardy–Weinberg equilibrium, and evaluation of associations between genotypes and milk production traits. In HF cows, genotype frequencies were 14.07% for A1A1, 60.18% for A1A2, and 25.75% for A2A2, while allele frequencies were 0.442 for A1 and 0.558 for A2. Similar genotype and allele distributions were observed in HF bulls, where the A2 allele frequency (0.560) was slightly higher than the A1 allele frequency (0.440). In Busha cows, a pronounced predominance of the A2 allele (0.719) and A2A2 genotype (56.25%) was detected. HF cows carrying the A2A2 genotype were associated with significantly higher milk yield, as well as higher milk protein and milk fat content, compared to cows with other genotypes (p < 0.05; p < 0.01). Milk production traits were generally higher during the second lactation, regardless of genotype. HF cows carrying the A2A2 genotype generally showed higher milk yield and more favorable milk composition traits. In addition, the high frequency of the A2 allele in Busha cattle indicates that this indigenous breed may represent a valuable genetic resource for the conservation and utilization of the A2 allele in future breeding programs. Full article

Background: Oral food challenge (OFC) remains the gold standard for diagnosing food allergy; however, it is time-consuming and associated with the risk of allergic reactions. The identification of reliable biomarkers capable of predicting OFC outcomes could improve patient selection and reduce the number of OFCs required in clinical practice. Among the most widely used biomarkers are skin prick tests (SPTs) and serum-specific IgE (sIgE) measurements, including component-resolved diagnostics. However, their diagnostic utility, as well as the comparability of different diagnostic platforms, remains incompletely defined in cow’s milk (CM) and hen’s egg (HE) allergy. Methods: We retrospectively analyzed results of diagnostic tests obtained in children undergoing OFCs to baked milk, raw milk, baked egg, and boiled egg. Diagnostic performance of SPTs to either allergen extracts or native food allergens, as well as sIgE measured using ImmunoCAP and ALEX2 platforms, was evaluated using receiver operating characteristic (ROC) analysis and logistic regression models. Results: Diagnostic performance varied across allergy phenotypes. SPTs to native food allergens demonstrated good discriminative capacity for raw milk and boiled egg allergy, whereas SPTs to standardized extracts showed limited diagnostic utility overall. In baked milk allergy, casein-sIgE measured by ImmunoCAP demonstrated the best diagnostic performance. In raw milk allergy, α-lactalbumin-sIgE measured using ALEX2 platform and β-lactoglobulin-sIgE measured by ImmunoCAP showed greater diagnostic relevance than casein-sIgE. In boiled egg allergy, SPT to raw egg yolk demonstrated the highest diagnostic value. In baked egg allergy, ovalbumin-sIgE measured using the ALEX2 platform showed the best performance, while ovomucoid-sIgE did not demonstrate clear superiority. ALEX2 showed good concordance with ImmunoCAP despite systematic differences in absolute sIgE values. Combined multivariable models provided only modest improvements over single predictors and did not achieve sufficient accuracy to replace OFCs. Conclusions: SPTs to either allergen extracts or native food allergens, as well as sIgE measurements, demonstrate moderate and heterogeneous utility in predicting OFC outcomes for CM and HE allergy. Although ALEX2 and ImmunoCAP showed comparable overall performance, platform-specific interpretation may be required. OFC remains indispensable for definitive diagnosis. Full article

A2 milk has recently gained popularity, mainly due to its different beneficial effects on the human digestive system compared to popular A1 milk. Because of these structural differences, A2 milk exhibits characteristics that need to be investigated to design processes appropriately. The effects of β-casein genotype and heat treatment method (LTLT, HTST, and HTLT: a high-temperature preparatory treatment applied in fermented dairy production) on the fatty acid profile, volatile organic compounds (VOCs), composition, emulsion stability, acidification kinetics, and color parameters were investigated. Fatty acid composition was determined exclusively by milk type. A1 milk exhibited higher saturated fatty acids, higher total PUFA content, higher Σn-3 fatty acids, and a more favorable n-6/n-3 ratio, while A2 milk showed higher monounsaturated fatty acids and higher CLA (Conjugated Linoleic Acid) in a trait-dependent manner. VOC profiling identified 29 compounds. Significant genotype × treatment interactions were observed: A1 milk was characterized by high diacetyl in fresh samples and exclusive methanethiol formation upon pasteurization, while A2 milk showed enhanced Maillard-derived volatile formation and high ester accumulation after LTLT treatment. Emulsion stability was highest after LTLT treatment regardless of milk type. A1 milk reached the coagulation threshold of pH 4.6 within 45 min, whereas A2 exhibited delayed acidification. HTLT induced the greatest color changes in both types of milk. Full article

Mare milk is rich in nutrients and bioactive compounds, and its composition changes throughout lactation. This study investigated variations in the production, nutritional composition, and bioactive components of Yili mare milk across lactation stages. Twenty-six healthy grazing Yili mares were sampled on days 1, 10, 30, 60, 90, and 120 of lactation. Milk production, nutritional components, amino acids, fatty acids, minerals, vitamins, and immunologically active proteins were analyzed. Milk production peaked on day 30 and then declined. Colostrum contained significantly higher fat, protein, solids-not-fat, total solids, minerals, lactoferrin, lysozyme, and immunoglobulins than mature milk (p < 0.05), whereas lactose increased and stabilized after day 30. Essential amino acids peaked on day 30. As lactation progressed, saturated fatty acids decreased while polyunsaturated fatty acids increased. Vitamin profiles also varied across lactation, with ascorbic acid increasing during late lactation. β-casein content was higher during mid-lactation. In summary, colostrum is enriched in immunoactive proteins and minerals, whereas mature milk exhibits a more balanced amino acid and fatty acid profile. While these observed variations likely reflect the combined effect of lactation stage and seasonal pasture fluctuations under natural grazing, these findings provide practical insights into changes in milk composition in grazing Yili mares and may support the development of mare milk products under similar grazing systems. Full article

Genetic screening of monogenic traits is important for improving genetic health and increasing favorable milk protein in dairy cattle. This study developed and applied an amplification refractory mutation system PCR (ARMS-PCR) assay to simultaneously screen 21 causal variants underlying 18 monogenic traits in Holstein cattle, including 13 recessive genetic defects, 2 milk protein loci, and 3 morphological loci. The assay was designed as a unified multiplex PCR-capillary electrophoresis workflow, enabling clear detection of allele-specific products distinguished by fragment size and fluorescent color. Sanger sequencing validation of newly incorporated loci supported the accuracy of the assay. A total of 1656 cows from 12 commercial farms were genotyped using the multiplex ARMS-PCR panel, and amplicons were analyzed by capillary electrophoresis. Carriers were detected for all genetic defects except DUMPS, with carrier frequencies ranging from 0.12% to 6.64%. The highest frequencies were observed for HH5 (6.64%) and MWS (6.58%), whereas HH3, HH1, and HCD showed intermediate frequencies of 1.81% to 3.08%; all the remaining defects were below 1%. Overall, 22.10% of sampled cows carried at least 1 defect allele, including 20.47% carrying 1 defect, 1.51% carrying 2, and 0.12% carrying 3. For milk protein loci, the desirable β-casein A2A2 and κ-casein BB genotypes occurred at frequencies of 45.83% and 14.13%, respectively, and the favorable A2A2/BB combination was present in 6.22% of sampled cows. Dominant red, recessive red, and polled alleles were rare. These results indicate that multiplex fluorescent ARMS-PCR can serve as a practical targeted screening tool for the simultaneous management of known deleterious alleles and selection of favorable monogenic variants in dairy cattle breeding. Full article

Mastitis limits yak dairy production and is associated with lipopolysaccharide (LPS)-mediated inflammation in yak mammary epithelial cells (YMECs). This study aimed to investigate the protective effect of caffeic acid (CA) against LPS-induced cellular injury and to elucidate the underlying mechanisms, with a particular focus on autophagy regulation via the NF-κB signaling pathway. LPS exposure strikingly reduced cellular viability and increased intracellular reactive oxygen species (ROS) levels, accompanied by activation of the NF-κB pathway. Furthermore, it increased the expression of pro-inflammatory cytokines (TNF-α, IL-8, and IL-1β). In addition, LPS enhanced endoplasmic reticulum (ER) stress and Ca²⁺ dysregulation, increased LC3-II/LC3-I ratio, and reduced synthesis of α-casein and β-casein. Pretreatment with CA resulted in the effective alleviation of these alterations by restoring cellular viability, suppressing inflammatory responses, and normalizing autophagy-related markers. Additionally, inhibition of Nrf2 reversed the partial reversal of the protective effects of CA, resulting in increased ROS accumulation and autophagy activation, but did not impact NF-κB suppression. These findings indicate that CA attenuates LPS-induced inflammatory injury in YMECs involved in both Nrf2-dependent and independent pathways. These findings provide a mechanistic analysis of yak mastitis pathogenesis and CA potential as a natural therapeutic for improving mammary health and milk quality in yak dairy systems. Full article

β-Casein A1 and A2 (β-CN-A1 and β-CN-A2) are the two predominant β-CN proteoforms in bovine milk. β-CN-A1 has been associated with a greater propensity to release opioid peptides, such as β-casomorphin-7 (β-CM-7) and β-casomorphin-5 (β-CM-5), during gastrointestinal (GI) digestion, which may have adverse biological effects. This has stimulated growing interest in milk from cows carrying the β-CN A2A2 genotype (A2 milk), which requires reliable characterization methods. In this work, we developed a rapid, selective, and sensitive capillary electrophoresis–mass spectrometry (CE-MS) method for the accurate identification and quantification of β-CM-7 and β-CM-5 in milk hydrolysates from in vitro GI digestion of bovine milk. The method showed good linearity (R² > 0.99, over 0.5–100 mg/L for β-CM-7 and 0.25–100 mg/L for β-CM-5), limits of detection (0.25 and 0.10 mg/L), and repeatability (<0.2% for times and <1.4% for areas), and tandem mass spectrometry (MS/MS) allowed confirmation. The method was applied to A1A1 and A2A2 milk digested using the standardized INFOGEST protocol, followed by solid-phase extraction. β-CM-7 was detected and quantified only in A1A1 digests (0.98 mg/L), whereas β-CM-5 was not detected (<0.10 mg/L). These results indicate a differential release of β-CMs from A1 and A2 milk and support the method’s suitability for β-CM profiling, which may help assess A2 milk quality control and β-CM health impact. Full article

Buffalo milk is a rich source of various nutritional components and bioactive peptides, offering significant health benefits. Endogenous peptides, which occur naturally in milk, represent a valuable source of bioactive peptides with potential nutraceutical applications. However, research on endogenous peptides in buffalo milk remains limited. This study employed a quantitative peptidomic approach to characterize endogenous peptides across different lactation stages. A total of 2099, 2946, and 4418 peptides were identified in colostrum, transitional milk, and mature milk, respectively. The majority of these peptides were derived from β-casein, followed by α_S1-casein, κ-casein, and other proteins. Notably, variations in precursor proteins contributing to peptide production were observed throughout lactation. Phosphorylation levels of endogenous peptides were highest in mature milk, with serine residues predominating. Enzymatic cleavage analysis identified cathepsin D as the key enzyme involved in endogenous peptide production, while proline endopeptidase and plasmin exhibited stage-specific activities. Bioinformatics analysis revealed differentially expressed precursor proteins linked to complement cascades and NF-κB signaling, emphasizing the immune protective role of colostrum. Furthermore, 54 potentially bioactive peptides with favorable water solubility were identified in colostrum, of which 17 were predicted to possess anti-inflammatory properties. These findings contribute to a deeper understanding of the molecular basis of buffalo milk’s functional properties, highlighting its potential as a source of bioactive peptides for both nutritional and pharmaceutical applications. Full article

This narrative review summarizes evidence on the bovine β-casein (CSN2) A1/A2 polymorphism as a case study of how intensive dairy selection and global gene flow can reshape allele frequencies in ways that matter for consumers, processing and agroecological resilience. We draw together evidence from (i) population-genetic surveys of CSN2 in contrasting cattle populations, including a descriptive summary of published genotype-frequency studies; (ii) controlled human studies that separate A1-containing from A2-only dairy exposure; and (iii) dairy technology and the authenticity literature relevant to identity-preserved A2 value chains. Across intensively selected Holstein-Friesian populations, A1 was consistently present at substantial frequency (approximately one-third), whereas indigenous, beef and zebu-adjacent populations were typically A2-enriched, highlighting the role of historical breed formation and modern introgression in shaping apparent geographic and climatic patterns. Human intervention studies most consistently support improved short-term gastrointestinal tolerance with A2-only milk in susceptible individuals, while evidence for longer-horizon systemic outcomes remains mixed and insufficient for causal disease claims. Processing and analytical studies suggest that β-casein genotype can modestly affect coagulation and product behavior in a context-dependent manner and that validated proteoform quantification coupled with traceability is essential for credible A2 labeling at scale. We discuss implications for breeding programs, including staged A2 selection that avoids performance trade-offs, and emphasize governance of artificial insemination and supply-chain segregation as levers to limit inadvertent allele diffusion while supporting climate-relevant genetic resources in locally adapted breeds. Collectively, the reviewed evidence suggests that A1/A2 β-casein can be usefully interpreted within a One Health framework spanning animal genetics, dairy systems and human tolerance research. Full article

Background: The first 1000 days of a child’s life, from a woman’s pregnancy to her child’s second birthday, represent a critical window during which nutritional and environmental exposures shape long-term health. Gut microbiota play an important role in metabolic and overall health. Although pet exposure during pregnancy affects neonatal microbiota, immunity, and development, its effects on maternal health remain unclear. This study investigated the associations of pet exposure with gestational health, maternal and infant microbiota, and breast milk composition in overweight/obese pregnant women. Methods: Fecal samples and breast milk samples were collected from pet-exposed participants (n = 22) and non-exposed controls (n = 32) for 16S rRNA sequencing. Breast milk lipids and proteins were also quantified. Results: Pet exposure before conception, during pregnancy, and postpartum was not associated with gestational diabetes mellitus or gestational weight gain. In the maternal gut, the relative abundances of Proteobacteria, Verrucomicrobia, Sutterellaceae, Enterobacteriaceae, Akkermansia muciniphila, and Parabacteroides were higher, whereas that of Ruminococcus was lower, in the pet-exposed group. In breast milk, the relative abundance of Escherichia-Shigella and the concentrations of phosphatidylinositol 36:2, phosphatidylethanolamine 38:3, lysine, and β-casein were higher, whereas the abundance of Rothia was lower, in the pet-exposed group. The relative abundance of Escherichia-Shigella was also lower in the infant gut of the pet-exposed group. Conclusions: In overweight/obese pregnant women, pet exposure was associated with differences in maternal gut and breast milk microbiota, higher concentrations of selected breast milk phospholipids and β-casein, and lower Escherichia-Shigella abundance in the infant gut. Full article