Impact of technological processes on buffalo and bovine milk fat crystallization behavior and milk fat globule membrane phospholipids profile

Comprehensive analysis of phospholipid in milk and their biological roles as nutrients and biomarkers

Phospholipids (PL) have garnered significant attention due to their physiological activities. Milk and other dairy products are important dietary sources for humans and have been extensively used to analyze the presence of PL by various analytical techniques. In this paper, the analysis techniques of PL were reviewed with the eight trigrams of phospholipidomics and a comprehensive fingerprint of 1295 PLs covering 8 subclasses in milk and other dairy products, especially. Technology is the primary productive force. Based on phospholipidomics technology, we further review the relationship between the composition of PL and factors that may be involved in processing and experimental operation, and emphasized the significance of the biological role played by PL in dietary supplements and biomarkers (production, processing and clinical research), and providing the future research directions.

Bioactive Functions of Lipids in the Milk Fat Globule Membrane: A Comprehensive Review

The milk fat globule membrane (MFGM) is a complex tri-layer membrane that wraps droplets of lipids in milk. In recent years, it has attracted widespread attention due to its excellent bioactive functions and nutritional value. MFGM contains a diverse array of bioactive lipids, including cholesterol, phospholipids, and sphingolipids, which play pivotal roles in mediating the bioactivity of the MFGM. We sequentially summarize the main lipid types in the MFGM in this comprehensive review and outline the characterization methods used to employ them. In this comprehensive review, we sequentially describe the types of major lipids found in the MFGM and outline the characterization methods employed to study them. Additionally, we compare the structural disparities among glycerophospholipids, sphingolipids, and gangliosides, while introducing the formation of lipid rafts facilitated by cholesterol. The focus of this review revolves around an extensive evaluation of the current research on lipid isolates from the MFGM, as well as products containing MFGM lipids, with respect to their impact on human health. Notably, we emphasize the clinical trials encompassing a large number of participants. The summarized bioactive functions of MFGM lipids encompass the regulation of human growth and development, influence on intestinal health, inhibition of cholesterol absorption, enhancement of exercise capacity, and anticancer effects. By offering a comprehensive overview, the aim of this review is to provide valuable insights into the diverse biologically active functions exhibited by lipids in the MFGM.

Lipidomics of Sannen goat milk subjected to pasteurization and spray drying based on LC-ESI-MS/MS

The purpose of this study was to evaluate the effects of pasteurization and spray drying on goat milk lipids by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) and multiple variable statistics. A total of 1061 lipids assigned to 29 subclasses in raw and thermal-treated groups were identified. One hundred and 85 different lipids (DLs) (VIP ≥ 1 and |Log₂FC| ≥ 1.0) were selected from pairwise comparisons of goat milk by different treatments. Glycerophospholipids were the most affected subclasses by thermal processes, especially by spray drying. Five potential lipid markers [(DG (16:1_18:0), TG (18:1_22:1_18:2), Cer (t17:2/31:0), LPC (0:0/20:0), and LPS (20:0/0:0] were used to distinguish different treated goat milk. Moreover, glycerophospholipid metabolism was the primary pathway of DLs. These results would provide more details of lipid profiles in thermally treated (pasteurization and spray drying) goat milk.

Effect of Buffalo Breed on the Detailed Milk Composition in Guangxi, China

Buffalo is the second source of milk in the world, and its milk is rich in nutritive components. It is well-known that breed influences milk composition. This work aimed to compare the detailed milk composition of three buffalo breeds (Murrah, Nili-Ravi, and Mediterranean) housed under the same environmental conditions. Mediterranean buffalo milk showed a significantly higher content of fat, protein, and some fatty acids. Moreover, the milk from the Mediterranean breed was characterized by the highest content of sphingomyelin (SM), cholesterol, and lanosterol. However, the Murrah buffalo milk contained the highest amount of total unsaturated fatty acids, phosphatidylinositol, and whey proteins. Furthermore, the Nili-Ravi buffalo milk was characterized by the highest content of total saturated fatty acids, phosphatidylglycerol, squalene, lathosterol, stigmasterol, beta-sitosterol, and casein fractions. Nevertheless, the lactose and amino acid profiles of the milk remained almost similar across the three buffalo breeds. The generated results in this study enable a comprehensive understanding of the milk constituent variability that is linked to buffalo breeds, which may support the acquirement of essential scientific knowledge on milk ingredient-processing interactions that will offer a foundation of knowledge for Chinese dairy processors in terms of milk processability and innovation.

Quantitative lipidomics analysis of changes in egg yolk lipids during spray-drying and subsequent accelerated storage

Egg yolks are rich in lipids that are easily altered during processing and storage. In this study, a liquid chromatography-tandem mass spectrometry strategy was used for quantitative lipidomics analysis of egg yolk after spray-drying processing and accelerated storage. Spray-drying treatment caused lipid oxidation (especially the oxidation of free fatty acids), potential hydrolysis of phospholipids, and alteration of the form of certain polyunsaturated fatty acids (docosahexaenoic acid, eicosapentaenoic acid, linolenic acid, and eicosatetraenoic acid) in egg yolk. These lipid alterations caused by the spray-drying process were further aggravated by the accelerated storage process. In detail, following storage, the abundance of free fatty acids, phosphatidic acid and phosphatidylethanolamine decreased further; and the abundance of polyunsaturated fatty acids in the form of triglycerides increased significantly. These results provide new insight into the mechanism underlying egg yolk property changes during spray-drying and storage, and offer valuable reference data for egg yolk powder promotion and application in food processing.

Milk polar lipids composition and functionality: a systematic review

Polar lipids including glycerophospholipids and sphingophospholipids are important nutrients and milk is a major source, particularly for infants. This systematic review describes the human and bovine milk polar lipid composition, structural organization, sources for formulation, and physiological functionality. A total of 2840 records were retrieved through Scopus, 378 were included. Bovine milk is a good source of polar lipids, where yield and composition are highly dependent on the choice of dairy streams and processing. In milk, polar lipids are organized in the milk fat globule membrane as a tri-layer encapsulating triglyceride. The overall polar lipid concentration in human milk is dependent on many factors including lactational stage and maternal diet. Here, reasonable ranges were determined where possible. Similar for bovine milk, where differences in milk lipid concentration proved the largest factor determining variation. The role of milk polar lipids in human health has been demonstrated in several areas and critical review indicated that brain, immune and effects on lipid metabolism are best substantiated areas. Moreover, insights related to the milk fat globule membrane structure-function relation as well as superior activity of milk derived polar lipid compared to plant-derived sources are emerging areas of interest regarding future research and food innovations.

Understanding the factors affecting the surface chemical composition of dairy powders: a systematic review

Dairy powder, with abundant chemical components such as protein, fat, and lactose possessing diverse physical and chemical structures, can exhibit a surface composition distinct from its bulk content during the conversion of liquid milk into dry powder. Surface chemical composition is a significant parameter in the dairy industry, as it is directly associated with the techno-functional properties of dairy powder products. The current work provides an overview of the factors influencing the surface composition of dairy powders such as the bulk composition of raw milk (animal source and formulation), liquid dairy processing (homogenization, thermal treatment, and evaporation), the drying process (drying methods as well as operating conditions during the most commonly used spray drying), and storage conditions (temperature, relative humidity, and duration). The underlying mechanisms involved in the variations of particle surface composition include the mechanical properties of emulsion, milk fat globules redistribution caused by mechanical forces, adsorption competition and interactions of ingredients at the water/air interface, dehydration-induced alterations in particle structure, corresponding solid/solutes segregation differentiation during spray drying, and lactose crystallization-induced increase in surface fat during storage. Additionally, future research is suggested to explore the effects of emerging processing technologies on the surface composition modification of dairy powders.

A Comparative Study of Milk Fat Extracted from the Milk of Different Goat Breeds in China: Fatty Acids, Triacylglycerols and Thermal and Spectroscopic Characterization

Goat milk (GM) is an excellent alternative to cow milk and has recently been used in commercial infant formula preparation due to its superior fat composition. Here, the fatty acid (FA) composition, triacylglycerol (TAG) molecular species, thermal behavior and infrared spectra of extracted milk fat from the milk of the two main breeds of dairy goat bred in China (Guanzhong GM (GZG) and Xinong Saanen GM (XSG)) are investigated. Gas chromatography, Fourier-transform infrared spectroscopy, differential scanning calorimetry and ultra-performance convergence chromatography with quadrupole time-of-flight mass spectrometry are applied. The obtained results evidence significant fat compositional differences based on the breed that produced the considered GM. The major FAs in both GM fats were capric (C10:0), myristic (C14:0), palmitic (C16:0), stearic (C18:0) and oleic (C18:1 n-9c). GZG presented a higher content of medium-chain saturated FAs, while XSG had higher unsaturated FAs with higher ratios of L/Ln and n-6/n-3. A total of 339 and 359 TAGs were detected and quantified in GZG and XSG, and the major TAGs were those of m/z 740.6712 (14.10 ± 0.27%) and m/z 684.6094 (10.94 ± 0.02%), respectively. Milk TAGs of GZG and XSG showed 24–54 and 26–54 total acyl carbon numbers with a 0–4 and 0–5 double bond number at 68 and 72 various retention times, respectively. Thermal analysis showed that all GM fat samples melted below normal body temperature. Infrared spectra revealed higher absorption values of GZG milk fat. This study provides valuable information to the dairy industry sector about GM fat produced in China, assessing the appropriateness of Chinese GM fat to be applied in Chinese infant formula.

Investigation of alterations in phospholipids during the production chain of infant formulas via HILIC-QTOF-MS and multivariate data analysis

Phospholipids play a key role in infant nutrition and cognitive function. In this study, hydrophilic interaction liquid chromatography coupled to quadrupole time-of-flight mass spectrometry method was firstly developed to analyze the composition of phospholipids. Then we characterized and quantified phospholipids extracted from raw, pasteurized, homogenized, and spray-dried milk to investigate the effect of the technological process on the composition of the phospholipids. Results indicate that the composition of the phospholipids underwent minor changes after pasteurization, while the concentration of phospholipids was significantly affected by the spray-drying process, especially phosphatidylethanolamine and phosphatidylinositol. Multivariate data analysis further verified the results and indicated that phospholipids containing polyunsaturated fatty acids had undergone significant changes during the production chain, especially in spray-drying. This work reveals the changes of phospholipids composition during the production chain of infant formulas and serve as a reference for the subsequent optimization of infant formulas to meet nutritional need of infants.

Bovine Milk Fats and Their Replacers in Baked Goods: A Review

Milk fats and related dairy products are multi-functional ingredients in bakeries. Bakeries are critical local industries in Western countries, and milk fats represent the most important dietary lipids in countries such as New Zealand. Milk fats perform many roles in bakery products, including dough strengthening, textural softeners, filling fats, coating lipids, laminating fats, and flavor improvers. This review reports how milk fats interact with the ingredients of main bakery products. It also elaborates on recent studies on how to modulate the quality and digestibility of baked goods by designing a new type of fat mimetic, in order to make calorie- and saturated fat-reduced bakery products. It provides a quick reference for both retailers and industrial manufacturers of milk fat-based bakery products.

Extraction of Dairy Phospholipids Using Switchable Solvents: A Feasibility Study

A tertiary amine (N,N-dimethylcyclohexylamine, CyNMe2) was used as a switchable hydrophilicity solvent (SHS) for extracting phospholipids (PLs) from raw cream (RC), buttermilk (BM), concentrated buttermilk (CBM), and beta-serum (BS). The SHS extractions were performed with varying solvent-sample weight ratio at room temperature. The extracted PLs using CyNMe2 were recovered by bubbling CO₂ at atmospheric pressure, switching the CyNMe2 into its respective salt. For comparison, the PLs were also extracted using Folch (FE) and Mojonnier (ME) extraction. The extraction efficiency of SHS varied from 0.33% to 99%, depending on the type of byproduct. The SHS extracted up to 99% of the PLs directly from BM, while only 11.37% ± 0.57% and 2.66% ± 0.56% of the PLs were extracted with FE and ME, respectively. These results demonstrate the applicability of SHS for the extraction of PLs from dairy byproducts.