Fatty acid profile and CLA isomers content of cow, ewe and goat milks processed by high pressure homogenization

Effect of homogenization on lipid profiling in Saanen goat milk based on UHPLC-QTOF-MS lipidomics

Homogenization might change the lipid composition of goat milk. This study aimed to investigate the lipid profiles, and identify different lipids (DLs) of raw goat milk (RGM) and homogenized goat milk (HGM) using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) and multivariate statistics. Fifty-six DLs (VIP ≥ 1 and |Log₂FC| ≥ 1.0) were identified from 1057 lipids assigned to 29 subclasses in RGM and HGM. Notably, there were many phosphatidylcholines (PCs) decreased after homogenization, while lysophosphatidylcholines (LPCs) were opposite. Our results provide more details on the impact of homogenization on goat milk lipids.

Determination of nutritional health indexes of fresh bovine milk using near infrared spectroscopy

Bovine milk is one of the most complete foods that exist. During the last decades, milk FA have shown to improve human health due to the reduction in risk of cardiovascular disease and related pathologies. The aim of this study was to evaluate the feasibility of near infrared spectroscopy (NIRS) reflectance analysis to predict the nutritional value, fatty acid (FA) composition, and health index of fresh milk from dairy cows of pastoral systems. The prediction of Atherogenicity and Thrombogenicity indexes, along with other FA ratios in fresh milk samples by NIRS were precise and accurate. In addition, the calibration model obtained by NIRS provides an opportunity for the routine quantification of milk’s healthy FA such as omega-3 and conjugated linoleic acid (CLA), with applications in the dairy industry for food labeling, and at the farm level for management of the dairy cow’s diet.

Applications of novel processing technologies to enhance the safety and bioactivity of milk

Bioactive compounds in food can have high impacts on human health, such as antioxidant, antithrombotic, antitumor, and anti-inflammatory activities. However, many of them are sensitive to thermal treatments incurred during processing, which can reduce their availability and activity. Milk, including ovine, caprine, bovine, and human is a rich source of bioactive compounds, including immunoglobulins, vitamins, and amino acids. However, processing by various novel thermal and non-thermal technologies has different levels of impacts on these compounds, according to the studies reported in the literature, predominantly in the last 10 years. The reported effect of these technologies either covers microbial inactivation or the bioactive composition; however, there is a lack of comprehensive compilation of studies that compare the effect of these technologies on bioactive compounds in milk (especially, caprine and ovine) to microbial inactivation at similar settings. This research gap makes it challenging to conclude on the specific processing parameters that could be optimized to achieve targets of microbial safety and nutritional quality at the same time. This review covers the effect of a wide range of thermal and non-thermal processing technologies including high-pressure processing, pressure-assisted thermal sterilization, pulsed-electric field treatment, cold plasma, microwave-assisted thermal sterilization, ultra-high-pressure homogenization, ultrasonication, irradiation on the bioactive compounds as well as on microbial inactivation in milk. Although a combination of more than one technology could improve the reduction of bacterial contaminants to meet the required food safety standards and retain bioactive compounds, there is still scope for research on these hurdle approaches to simultaneously achieve food safety and bioactivity targets.

High-Temperature Short-Time and Holder Pasteurization of Donor Milk: Impact on Milk Composition

Holder pasteurization (HoP; 62.5 °C, 30 min) is commonly used to ensure the microbiological safety of donor human milk (DHM) but diminishes its nutritional properties. A high-temperature short-time (HTST) system was designed as an alternative for human milk banks. The objective of this study was to evaluate the effect of this HTST system on different nutrients and the bile salt stimulated lipase (BSSL) activity of DHM. DHM was processed in the HTST system and by standard HoP. Macronutrients were measured with a mid-infrared analyzer. Lactose, glucose, myo-inositol, vitamins and lipids were assayed using chromatographic techniques. BSSL activity was determined using a kit. The duration of HTST treatment had a greater influence on the nutrient composition of DHM than did the tested temperature. The lactose concentration and the percentage of phospholipids and PUFAs were higher in HTST-treated than in raw DHM, while the fat concentration and the percentage of monoacylglycerides and SFAs were lower. Other nutrients did not change after HTST processing. The retained BSSL activity was higher after short HTST treatment than that following HoP. Overall, HTST treatment resulted in better preservation of the nutritional quality of DHM than HoP because relevant thermosensitive components (phospholipids, PUFAs, and BSSL) were less affected.

Evaluation of Downstream Processing, Extraction, and Quantification Strategies for Single Cell Oil Produced by the Oleaginous Yeasts Saitozyma podzolica DSM 27192 and Apiotrichum porosum DSM 27194

Single cell oil (SCO) produced by oleaginous yeasts is considered as a sustainable source for biodiesel and oleochemicals since its production does not compete with food or feed and high yields can be obtained from a wide variety of carbon sources, e.g., acetate or lignocellulose. Downstream processing is still costly preventing the broader application of SCO. Direct transesterification of freeze-dried biomass is widely used for analytical purposes and for biodiesel production but it is energy intensive and, therefore, expensive. Additionally, only fatty acid esters are produced limiting the subsequent applications. The harsh conditions applied during direct esterification might also damage high-value polyunsaturated fatty acids. Unfortunately, universal downstream strategies effective for all yeast species do not exist and methods have to be developed for each yeast species due to differences in cell wall composition. Therefore, the aim of this study was to evaluate three industrially relevant cell disruption methods combined with three extraction systems for the SCO extraction of two novel, unconventional oleaginous yeasts, Saitozyma podzolica DSM 27192 and Apiotrichum porosum DSM 27194, based on cell disruption efficiency, lipid yield, and oil quality. Bead milling (BM) and high pressure homogenization (HPH) were effective cell disruption methods in contrast to sonification. By combining HPH (95% cell disruption efficiency) with ethanol-hexane-extraction 46.9 ± 4.4% lipid/CDW of S. podzolica were obtained which was 2.7 times higher than with the least suitable combination (ultrasound + Folch). A. porosum was less affected by cell disruption attempts. Here, the highest disruption efficiency was 74% after BM and the most efficient lipid recovery method was direct acidic transesterification (27.2 ± 0.5% fatty acid methyl esters/CDW) after freeze drying. The study clearly indicates cell disruption is the decisive step for SCO extraction. At disruption efficiencies of >90%, lipids can be extracted at high yields, whereas at lower cell disruption efficiencies, considerable amounts of lipids will not be accessible for extraction regardless of the solvents used. Furthermore, it was shown that hexane-ethanol which is commonly used for extraction of algal lipids is also highly efficient for yeasts.

Milk fat components with potential anticancer activity-a review

During many years, the milk fat has been unfairly undervalued due to its association with higher levels of cardiovascular diseases, dyslipidaemia or obesity, among others. However, currently, this relationship is being re-evaluated because some of the dairy lipid components have been attributed potential health benefits. Due to this, and based on the increasing incidence of cancer in our society, this review work aims to discuss the state of the art concerning scientific evidence of milk lipid components and reported anticancer properties. Results from the in vitro and in vivo experiments suggest that specific fatty acids (FA) (as butyric acid and conjugated linoleic acid (CLA), among others), phospholipids and sphingolipids from milk globule membrane are potential anticarcinogenic agents. However, their mechanism of action remains still unclear due to limited and inconsistent findings in human studies.

Seasonal variation in fatty acid profile in the milk of different species under popularly followed feeding system in India

The aim of the study was to evaluate the seasonal variation in fatty acid profile in the milk of different species during summer and winter seasons. Samples were collected in months of summer and winter. Total saturated fatty acids (SFA) content (g/100g of fat) was 13-14% higher in summer than winter in all species. Total monounsaturated fatty acid (MUFA), polyunsaturated fatty acid (PUFA) and conjugated linoleic acid (CLA) concentration (g/100g fat) were 10-12%, 3-4%, 30-40% respectively and, higher in winter than summer. MUFA, PUFA and CLA were considerably altered among seasons and species. It was concluded that PUFA and CLA in milk of different species increased during winter season than summer and this may be attributed to the seasonal availability of green fodder.

Milk and blood biomarkers associated to the clinical efficacy of a probiotic for the treatment of infectious mastitis

Previous studies have shown the efficacy of oral administration of selected lactobacilli strains to treat mastitis. The objective of this study was to find microbiological, biochemical and/or immunological biomarkers of the probiotic effect. Women with (n=23) and without (n=8) symptoms of mastitis received three daily doses (10(9) cfu) of Lactobacillus salivarius PS2 for 21 days. Samples of milk, blood and urine were collected before and after the probiotic intervention, and screened for a wide spectrum of microbiological, biochemical and immunological parameters. In the mastitis group, L. salivarius PS2 intake led to a reduction in milk bacterial counts, milk and blood leukocyte counts and interleukin (IL)-8 level in milk, an increase in those of immunoglobulin (Ig)E, IgG3, epidermal growth factor and IL-7, a modification of the milk electrolyte profile, and a reduction of some oxidative stress biomarkers. Such biomarkers will be useful in future clinical studies involving a larger cohort.

Microstructural and lipid composition changes in milk fat globules during milk powder manufacture

The purpose of this study was to investigate the effects of milk powder processing conditions (pasteurisation, homogenisation and spray-drying) on the microstructure and composition of fat globules in cow milk.

Effects of sun and freeze-drying techniques on molecular, fatty acid and therapeutic properties of fermented goat milk product

This study investigated the effect of sun drying (Sd) and freeze drying (Fd) on the chemical, nutritional and biological properties of either unsalted (Us) or salted (Sa) Jameed produced from goat milk. The products were characterized by measuring the chemical, physical and biological properties. SDS-PAGE was used to characterize the effect of processing conditions on protein subunits. Major new bands were found in SDS-PAGE of Jameed prepared by SdUs and FdUs from goat milk but not from that prepared by SdSa and FdSa. Preparation of Jameed by with or without salt treatments of Jameed by sun drying enhances the contents of short chain fatty acids. Result showed that the preparation of Jameed by SdUs decreased the content of caprylic acid. That prepared by sun drying and with or without salt increased the stability, shelf life and inhibitory activities of ACE and α-amylase. The optimum color values were found in Jameed prepared by FdSa. Different processing treatments influenced content of all fatty acids except for margaric and oleic acid.

Especies ibéricas de los géneros <i>Lithurgus</i> Berthold, 1827, <i>Creightonella</i> Cockerell, 1908 y <i>Chalicodoma</i> Lepeletier, 1841 (Hymenoptera, Megachilidae): claves de identificación y nuevos datos de distribución

El presente trabajo, dentro de la revisión que se está realizando sobre la familia Megachilidae en la fauna ibérica, incluye las claves de identificación y aporta nuevos datos de distribución para las especies de tres géneros: Lithurgus (tres especies), Creightonella (una) y Chalicodoma (ocho). Las claves se acompañan de dibujos y fotografías ilustrativos que permiten el reconocimiento tanto de las especies como de las subespecies.

Fat composition of organic and conventional retail milk in northeast England

This study of UK retail milk identified highly significant variations in fat composition. The survey, conducted over 2 yr replicating summer and winter, sampled 22 brands, 10 of which indicated organic production systems. Results corroborate earlier farm-based findings considering fat composition of milk produced under conventional and organic management. Organic milk had higher concentrations of beneficial fatty acids (FA) than conventional milk, including total polyunsaturated fatty acids (PUFA; 39.4 vs. 31.8 g/kg of total FA), conjugated linoleic acid cis-9,trans-11 (CLA9; 7.4 v 5.6 g/kg of FA), and α-linolenic acid (α-LN; 6.9 vs. 4.4 g/kg of FA). As expected, purchase season had a strong effect on fat composition: compared with milk purchased in winter, summer milk had a lower concentration of saturated fatty acids (682 vs. 725 g/kg of FA) and higher concentrations of PUFA (37.6 vs. 32.8 g/kg of FA), CLA9 (8.1 vs. 4.7 g/kg of FA), and α-LN (6.5 vs. 4.6 g/kg of FA). Differences identified between sampling years were more surprising: compared with that in yr 2, milk purchased in year 1 had higher concentrations of PUFA (37.5 vs. 32.9 g/kg of FA), α-LN (6.0 vs. 5.1 g/kg of FA), and linoleic acid (19.9 vs. 17.5 g/kg of FA) and lower concentrations of C16:0 and C14:0 (332 vs. 357 and 110 vs. 118 g/kg of FA, respectively). Strong interactions were identified between management and season as well as between season and year of the study. As in the earlier farm studies, differences in fat composition between systems were greater for summer compared with winter milk. Large between-year differences may be due to changes in weather influencing milk composition through forage availability, quality, and intake. If climate change predictions materialize, both forage and dairy management may have to adapt to maintain current milk quality. Considerable variation existed in milk fat composition between brands.

Recent trends in the advanced analysis of bioactive fatty acids

The consumption of dietary fats have been long associated to chronic diseases such as obesity, diabetes, cancer, arthritis, asthma, and cardiovascular disease; although some controversy still exists in the role of dietary fats in human health, certain fats have demonstrated their positive effect in the modulation of abnormal fatty acid and eicosanoid metabolism, both of them associated to chronic diseases. Among the different fats, some fatty acids can be used as functional ingredients such as alpha-linolenic acid (ALA), arachidonic acid (AA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), gamma-linolenic acid (GLA), stearidonic acid (STA) and conjugated linoleic acid (CLA), among others. The present review is focused on recent developments in FAs analysis, covering sample preparation methods such as extraction, fractionation and derivatization as well as new advances in chromatographic methods such as GC and HPLC. Special attention is paid to trans fatty acids due its increasing interest for the food industry.