Immunomodulatory peptides from milk(IPM)are a class of polypeptides with various biological activities such as immunomodulatory,antibacterial,and antioxidant properties.Compared to microbial fermentation,enzymatic hydrolysis offers distinct advantages including high specificity for cleavage sites,defined product structures,and superior process controllability,making it the preferred strategy for producing high-potency,standardized IPMs.This review summarizes recent advances in the enzymatic preparation of IPMs,focusing on enzyme selection strategies and the structure-activity relationship of IPMs regarding charge,hydrophobicity,and peptide chain length.Furthermore,it discusses the bidirectional mechanisms of IPMs in modulating innate and adaptive immunity,and highlights core industrial challenges such as debittering,membrane fouling control,and low oral bioavailability.Future research should integrate artificial intelligence assisted virtual screening and nano-encapsulation technologies to overcome bottlenecks in the application of IPMs.
Dairy flavor is a product of the synergistic interaction between microbial metabolism and processing techniques,with its unique sensory characteristics being critical determinants of product competitiveness and quality control.This review systematically summarizes the formation mechanism of dairy flavor and the principles and applications of major identification,screening,and quality evaluation technologies,with a focus on the advantages,limitations,and complementary relationships of gas chromatography-mass spectrometry,liquid chromatography-mass spectrometry,near-infrared(NIR)spectroscopy,nuclear magnetic resonance,and intelligent sensory technologies.Based on a systematic comparison of existing techniques,a"technology characteristic-detection objective-application scenario"matching framework is proposed,aiming to shift the current research paradigm from reliance on"single-technology identification"toward an integrated approach based on"multi-technology fusion perception".This shift provides a theoretical foundation and technical support for establishing a standardized and intelligent dairy flavor evaluation system.Future developments are expected to focus on the construction of multi-technology collaborative platforms,in-depth interpretation of complex data using artificial intelligence algorithms,and online quality control enabled by miniaturized devices.
The standards for infant and young child formulae of China,the Codex Alimentarius Commission(CAC),the European Union(EU),Australia and New Zealand(ANZ),and the United States were compared with respect to energy,protein,fat,and optional ingredients to identify differences in nutritional requirements.It was found that China has established stringent standards for infant,follow-on,and young child formulae.The Chinese and CAC standards for infant and follow-on formulae are highly consistent,with nearly identical limits set for essential nutrients such as energy,total fat,total carbohydrates,protein,and vitamins.The major difference between them is that the addition of inositol and L-carnitine is mandated by the CAC,while these compounds are classified as optional ingredients in China.The limits set by China for essential ingredients such as energy,fat,and carbohydrates are consistent with those from the EU standards,while the limits for 13 nutrients including vitamins A and D are higher than those from the EU standards.Additionally,the EU has mandated the addition of inositol,L-carnitine,and docosahexaenoic acid,and has approved seven human milk oligosaccharides(HMOs)for use in infant formula.In contrast,only two HMOs have been approved in China.These variations can be attributed to differences in breast milk composition data,infant dietary patterns,nutritional deficiency status,and regulatory philosophies among countries.This paper clarifies the similarities and differences in the nutritional requirements of domestic and international standards for infant and young child formulae,providing crucial insights for refining China's regulatory revisions and guiding consumers in selecting products that meet the nutritional needs of local infants and young children.
The proliferation of small intestinal epithelial cells is fundamental to intestinal development and barrier function maintenance in infants and young children. To investigate the effects and mechanisms of u03C9-3 polyunsaturated fatty acids (docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)), commonly used in infant formula, on this process, this study employed the rat intestinal epithelial cell line 6 (IEC-6) as a model. After DHA and EPA treatment at different combinations of concentration (1, 10, 50, 100 u03BCmol/L) and duration 12, 24, 36, 48 h, cell viability was assessed using the cell counting kit-8 and 5-ethynyl-2u2019-deoxyuridine assays, and the mRNA and protein expression of key molecules involved in the Wnt/u03B2-catenin signaling pathways were analyzed via real-time quantitative polymerase chain reaction and Western blot. The results showed that both DHA and EPA significantly promoted the proliferation of IEC-6 cells, with optimal concentrations of 100 and 10 u03BCmol/L, respectively, and an optimal treatment duration of 24 h. Specifically, treatment with 100 u03BCmol/L DHA and 10 u03BCmol/L EPA for 24 h increased cell viability by nearly 4- and 3.5-fold compared to the control group (P u0026lt; 0.001), respectively. Both DHA and EPA activated the Wnt/u03B2-catenin signaling pathway, significantly upregulating the mRNA and protein expression of cell proliferation-related genes such as cyclin D1 and u03B2-catenin (P u0026lt; 0.05, P u0026lt; 0.01, or P u0026lt; 0.001). These findings indicate that DHA and EPA enhance intestinal epithelial cell proliferation by activating the Wnt signaling pathway.
The effects of heat sterilization and microwave sterilization on the stability and casein structure of fresh camel milk were compared.The microwave sterilization conditions were optimized using single factor experiments and response surface methodology based on Box-Behnken design.Changes in the structure and properties of camel milk casein after sterilization were investigated using a differential scanning calorimeter,a Fourier transform infrared spectrometer,and a scanning electron microscope.The centrifugal sedimentation rate of protein and the total number of colonies were taken as response variables,the optimum conditions were determined as follows:pH 7.0,microwave power 560 W and microwave irradiation time 120 s.After microwave treatment under these conditions,the centrifugal sedimentation rate of protein was 6.96%,and no bacterial colonies were detected.Differential scanning calorimetry(DSC)plot showed that microwave treatment resulted in higher enthalpy of camel milk casein compared with heat sterilization,indicating a lower degree of denaturation and higher stability.The results of scanning electron microscopy showed that both sterilization methods destroyed the micellar structure of casein to varying degrees,resulting in cross-linking and aggregation.However,after microwave sterilization,the casein showed ordered aggregation,forming small aggregates that assembled into an ordered network structure.Appropriately increasing the pH of camel milk before sterilization was conducive to its stability.Different sterilization methods had a significant effect on the secondary structure of camel milk casein.Both microwave and heat sterilization reduced the relative contents of α-helix and β-turn in the casein.The relative content of β-sheet in heat-sterilized camel milk casein was the highest,indicating the most significant change in the secondary structure of the protein.In summary,this study revealed the stability of camel milk and the structural change of camel milk casein under different sterilization conditions,which can help address the poor stability of thermally sterilized camel milk at this stage.
