Anhydrous Milk Fat Research Articles

Sensory Features of Partially Hydrogenated Oil and Their Connection with Melting and Crystalline Characteristics.

Although partially hydrogenated oil (PHO) provides foods with outstanding thick tastes and pronounced "creamy" flavor, the high level of artificial trans-fatty acids (TFA; about 30%) limits its usages around the world in the near future. It is necessary to produce trans-free alternatives with similar tastes to PHO. The relationship between sensory attributes and physicochemical characteristics of PHO and four typical specialty fats were therefore analyzed in the present study. PHO exhibited the highest greasiness score (8.19), accompanying by mild creaminess and aftertaste as well as a weak coolness during swallow, which were resulted from the close-packed arrangements of TFA, its cis-counterparts and other long chain fatty acids. None of artificial trans-fats, mainly anhydrous milk fat, cocoa butter, and coconut oil and its fully hydrogenated counterpart, were similar to PHO in terms of these sensory attributes. The unique fatty acid species of PHO and their arrangements contributed to the relatively smooth solid fat content profile and melting-crystallization curve, as well as forming uniform and dense β' crystal-structures (Db=1.80). The Pearson correlation analyses relevelled that long chain fatty acids, e.g., t-C18:1 and C18:1, and melting final temperatures were generally positive correlated with greasiness, creaminess and aftertaste; whereas these indices were negatively correlated with coolness. The melting enthalpy was highly connected with coolness, which reflected the endothermic effectiveness during the melting process of fats in the mouth. These indices screened by correlation analyses that were strongly correlated with sensory attributes could provide references for producing trans-free alternatives.

Characterising the mechanical properties of soft solids through acoustics and rheology, exemplified by anhydrous milk fat.

Foods vary in their elastic properties over a wide range of behaviours. In the case of mastication, textures vary from hard solid through brittle (chocolate bar) and crispy/crunchy (biscuits) to viscous and extensional flow (syrup) and finally very low viscosity fluid (water). Here we deploy an elastic description of soft solids which embraces all these behaviours to quantify the elastic behaviour of food, in particular through the use of sound. We illustrate the use of this mathematical description in the quantitative characterisation of the elastic and flow properties of food through orthodox measurement techniques and novel ultrasound methods. Measurement is complicated by human sensory capabilities that span the entire range from solid to fluid to gas in an integrated manner, during the appreciation of food. We use acoustic and rheological measurement techniques for the determination of the mechanical properties of soft solids, comparing oscillatory rheometry with acoustic parameters as exemplified by acoustic and oscillatory rheometry measurements in crystallising anhydrous milk fat (AMF). We conclude that acoustic and rheological measurements complement each other with acoustic techniques offering the possibility of inline, in process determination of mechanical and flow properties such as viscosity, rigidity, compressibility and bulk modulus.

Quality of milk fat obtained from cows and buffaloes fed a diet supplemented with flaxseed or soybean oils

The experiment was carried out to evaluate the quality of anhydrous milk fat (AMF) of cows and buffaloes supplemented with flaxseed oil (FO), soybean oil (SO), or their mixture (FSO). Lactating crossbred cows and buffaloes were fed with control diet or with one of three supplements: 2% FO, 2% SO, and 2% FSO according to a double 4 x 4 Latin Square Design. The diets with FO, SO, or FSO reduced saturated FA, mainly C4:0, C14:0 and C16:0, while increased the unsaturated FA C18:1 and C18:2 in milk from cows and buffaloes. Cholesterol content decreased in cow's AMF while increased in buffalo's AMF when a diet supplemented with FO, SO, or FSO. The diet with SO or FSO increased the content of vitamin E in AMF obtained from cows (25.06 and 17.89 mg 100 g-1) and buffaloes (28.48 and 30.32 mg 100 g-1) compared with the control diet (11.02 and 15.68 mg 100 g-1), respectively, which correlated positively with scavenging activity for DPPH• (r2 = 0.66) and ABTS• (r2 = 0.67) radicals. Solid fat content (SFC) was high for cow’s AMF, with 58.12-60.37% at 5°C compared to that of buffalo's AMF, with 52.37-56.98%, but was low for cow's AMF at >15°C. Finally, supplementing a diet with vegetable oils, particularly SO, improves the quality of AMF; increases USFA/SFA ratio, vitamin E content, and antioxidant activities

Effects of Milk Polar Lipids on DSS-Induced Colitis Severity Are Dependent on Dietary Fat Content

In the United States, over three million adults suffer from inflammatory bowel disease (IBD). The gut microbiome, host immune response, and nutrient-microbial interactions are known to play a role in IBD. The relationship between dairy and IBD is controversial; thus, the objectives of this study were to identify how milk polar lipids (MPLs) and anhydrous milk fat affect colitis disease activity, the colonic transcriptome, and the gut microbiome in a mouse model of chemical-induced colitis. Male and female C57BL/6J mice (n = 120) were randomized into either a low (5% w/w) milk fat or a high (21% w/w) milk fat diet supplemented with either 0%, 1%, or 2% w/w of MPLs for three weeks (n = 10/group/sex). Afterwards, colitis was induced using 1% dextran sodium sulfate in drinking water for five days (colitis induction) and then switched to regular water for five days (colitis recovery). Mice fed added MPLs were protected against colitis when fed a high-fat diet, while added MPLs during low-fat diet attenuated disease activity during the colitis induction period yet promoted colitis and inflammation in male mice during the recovery period. Dietary fat content can alter colitis and influence the anti-inflammatory effect of milk polar lipids.

Crystallization behavior of milk fat, palm oil, palm kernel oil, and cocoa butter with and without the addition of cannabidiol

AbstractThe objective of this study was to evaluate the effect of cannabidiol (CBD) on the crystallization behavior and physical properties of various fats. Anhydrous milk fat (AMF), palm oil (PO), palm kernel oil (PKO), and cocoa butter (CB) were chosen for this study, for their unique crystallization behaviors. CBD was added at 1 and 2.5% wt/wt to these fats, and the crystallization behavior was evaluated at 26°C for AMF and PO and at 22°C for PKO and CB. Control samples with no CBD were prepared and evaluated as well. Results show that CBD delayed the crystallization of all fats with the least effect observed for the PO. Slight increases in crystal size were observed with the addition of CBD for all samples. CBD did not affect the melting profile of AMF or CB, but it increased the peak temperature of PO and decreased the enthalpy of PKO. Similarly, hardness was only affected by CBD in PO samples, with harder materials obtained for samples containing 2.5% CBD. The same trend was observed for elasticity. In addition, the elasticity of AMF increased with the addition of CBD but not its hardness. Overall, this study indicates that the effect of CBD on fat crystallization is highly dependent on the type of fat used. Producers of fat‐based products that are willing to include CBD in their formulations must carefully control processing conditions to ensure product quality.

Oxidative stability and health-related indices of anhydrous milk fat and vegetable oil blends

Anhydrous milk fat (AMF), although relatively resistant to oxidation due to its low content of polyunsaturated fatty acids (FAs), raises certain health concerns due to a high saturated FAs content. Blending AMF with other edible fats is an ideal strategy for modifying its FA profile, health-promoting properties and oxidative stability. Addition of 30% vegetable oils to AMF significantly modified its FA profile. Oils with a high unsaturated FAs content, i.e., walnut, grapeseed and linseed oils, were particularly effective in increasing the content of unsaturated FAs in AMF and reducing its atherogenicity index and thrombogenicity index. AMF and vegetable oil blends were characterised by higher oxidative stability than pure vegetable oils. Blends comprising AMF and oils abundant in monounsaturated FAs, i.e., hazelnut, rapeseed and peanut oils, were most resistant to oxidation. Depending on intended use, the properties of AMF can be easily and cheaply modified through blending with selected vegetable oils.

Triacylglycerol composition and thermodynamic profiles of fractions from dry fractionation of anhydrous milk fat

This research provided a more in-depth look at the physiochemical properties of milk fat. The milk fat was fractionated between 30 and 15 °C into eight fractions with different melting points, the cooling step were successively 30, 25, 20 and 15 ℃. Physiochemical properties of different fractions, which include fatty acids, triacylglycerols, thermodynamics, and crystallization behavior, also were analyzed by using GC, UPLC-ESI MS, DSC and XRD. The results showed that the melting point of 30 S could reach 38.2 ℃ compared with the native milk fat (31 ℃) after fractionation. As the fractionation temperature decreased, the content of long-chain saturated fatty acids decreased. However, the content of short and medium-chain saturated fatty acids and unsaturated fatty acids showed an increasing trend, and the corresponding saturated triacylglycerols were also reduced. Besides, the high melting point fractions were mixed dominantly by β' crystal form at room temperature. The crystallization or melting temperature was relatively high, and the latent heat of phase change also was large. Therefore, these results demonstrated that the milk fat quality could be improved by dry fractionation and its application was expanded in production.

Crystallization and phase behavior in mixture systems of anhydrous milk fat, palm stearin, and palm oil: Formation of eutectic crystals

The comparison between the crystallization and phase behavior of binary blends of anhydrous milk fat (AMF)/palm stearin (POs) and POs/palm oil (PO) was investigated. POs/POs blends showed good compatibility, while the compatibility of AMF/POs blends showed no ideal and was dominated by eutectic behavior. And the eutectic growth of blends was found to be a phenomenon that the triacylglycerol (TAG) of AMF grew on the peripheral of POs seed crystals. In binary blends, the addition of POs not only increased the liquid phase transition temperature but also induced the formation of β crystal forms in more than 70% POs. The addition of soybean oil to binary blends could improve the compatibility of the ternary system. It eventually provided potential formulations for the production of non-hydrogenated puff pastry margarine.

Structural and Vibrational Investigations of Mixtures of Cocoa Butter (CB), Cocoa Butter Equivalent (CBE) and Anhydrous Milk Fat (AMF) to Understand Fat Bloom Process

Some studies found that the proportions of cocoa butter (CB), cocoa butter equivalent (CBE) and milk fatty acid (AMF) tend to influence the blooming delay when mixing them. The goal of our research is to determine the effects of the proportion of CB, CBE and AMF on the structural organization of the final mixtures. X-ray, DSC, MIR and Raman spectroscopy were used to analyze the structural features and the vibrational modes of four mixtures: CB + 0.5AMF, CB + AMF, CB + 0.5AMF + CBE and CB + AMF + CBE. At room temperature, the triglycerides are ingredients of CB, and CBE and AMF do not fully exhibit the known crystalline forms V or VI, unlike a recent CB sample. Part of these triglycerides is in the form IV instead. The presence of the latter seems to be a key parameter that favors the deceleration of the transformation to the form VI, which is responsible for the development of fat bloom.

Multi‐country outbreak of monophasic Salmonella Typhimurium sequence type 34 linked to chocolate products – first update – 18 May 2022

On 17 February 2022, the United Kingdom (UK) reported a cluster of cases with monophasic Salmonella Typhimurium sequence type 34 infection. As of 18 May 2022, 324 cases had been reported in 12 EU/EEA countries and the UK, including two distinct strains. Most cases are below ten years of age and 41% of all cases have been hospitalised. The two strains are multidrug-resistant and some tested isolates also carry resistance to disinfectants that are based on quaternary ammonium compounds and hydrogen peroxide, but remain susceptible to azithromycin, ciprofloxacin, meropenem, and third generation cephalosporins. Epidemiological investigations suggested specific chocolate products of Brand A, produced by Company A in Processing Plant B in Belgium, as likely vehicles of infection. Two strains of monophasic Salmonella Typhimurium matching the outbreak strains were identified in the anhydrous milk fat (AMF) buttermilk line at Plant B between December 2021 and January 2022. The AMF buttermilk was provided by an Italian supplier where Salmonella was not detected. This supplier delivered the AMF buttermilk to other plants of Company A where, based on the available evidence, Salmonella was not detected. On 8 April 2022, based on official controls, the food safety authority in Belgium decided to withdraw the authorisation for production of the Plant B due to lack of transparency and insufficient guarantees for safe production. Company A globally recalled all products of Brand A produced at Plant B. Public warnings were issued by the competent national authorities in different countries. This outbreak has evolved rapidly, with children most at risk for severe infection. The closure of Plant B and the global recall of all their products have reduced the risk of exposure. However, eight cases cannot be explained by consumption of chocolate products such as those manufactured at Plant B, suggesting that there may also be other sources of infection.

The effect of fat replacement by whey protein microcoagulates on the physicochemical properties and microstructure of acid casein model processed cheese

Attempts to minimise fat content in popular food products have been made in the past. Research shows that microcoagulated forms of whey proteins can replace fat; they are capable of thickening the cheese mass and act as fat mimetics. This study investigated the effect of whey protein microcoagulates, as a fat replacer, on the textural, rheological properties, meltability, and microstructure of model processed cheese prepared using acid casein. Partial replacement of anhydrous milk fat with whey protein microcoagulates (3–8%) increased hardness and viscosity of model processed cheeses. Storage modulus (G′) was higher than the loss modulus (G″) during the whole experiment. The observed change in physicochemical properties, demonstrated by higher viscosity or ample meltability, suggests that whey protein microcoagulates can be utilised as a potential fat replacer in processed cheese.

Digestive protection of probiotic Lacticaseibacillus rhamnosus in Ricotta cheese by monoglyceride structured emulsions

SummaryThis research aimed at studying the potential use of monoglyceride (MG) structured emulsions (MSEs) as delivery and protective systems for probiotic bacteria in Ricotta cheese. To this purpose, a low‐fat commercial Ricotta cheese was added with MSEs formulated with milk, as water phase, and sunflower oil (MSE‐SO) or anhydrous milk fat (MSE‐AMF), as lipid phase. A commercial whole milk Ricotta cheese (W‐RC) was considered as reference. A probiotic Lacticaseibacillus rhamnosus strain was inoculated as free cells in W‐RC or embedded into the MSEs and added to the low‐fat Ricotta at the same reference fat content. After physico‐chemical characterisation, L. rhamnosus viability and sample destructuring behaviour upon in vitro digestion were evaluated. At the end of in vitro digestion, both W‐RC and sample containing MSE‐SO were unable to protect cells. By contrast, sample with AMF ensured a sufficient probiotic viability, even after 14 days of storage at 4 °C. This result was attributed to system composition and structure. During the gastric phase, the presence of caseins and MG‐AMF mixed structures induced the formation of clots, entrapping and protecting cells against the acidic pH of the stomach, as confirmed by confocal micrographs and particle size. During the intestinal phase, cell viability was guaranteed by the formation of mixed micelles promoted by MG. It was demonstrated that microbial cells located near MG structures where they found protection.

Thin-film convective cooling-crystallisation characteristics of anhydrous milk fat (AMF)

Thin-film cooling experiments were used to investigate how different convective cooling rates control the solidification behaviour of anhydrous milk fat. The solidification behaviour of the anhydrous milk fat manifested only in the smooth augmentation of the cooling curves, as opposed to the expected kink or bump in the curves observed for olive oil. Ascertaining this required the use of a lump convective heat transfer framework coupled with a simplified semi-infinite heat conduction scheme developed in this work. Analysis of the exothermic energy history of the solidification process suggested different lamellar structures in the solidified anhydrous milk fat under varying convective cooling conditions. • Thin-film technique capturing the AMF convective cooling characteristics. • AMF cooling curves did not exhibit any significant crystallisation bump or kink. • A mathematical framework that discerns the onset of AMF crystallisation. • The convective cooling rate affects the AMF crystallisation exothermic history.

Mixed dairy and plant-based yogurt alternatives: Improving their physical and sensorial properties through formulation and lactic acid bacteria cocultures

Food transition requires incorporating more plant-based ingredients in our diet, thus leading to the development of new plant-based products, such as yogurt alternatives (YAs). This study aimed at evaluating the impact of lactic acid bacteria (LAB) cocultures and formulation on the physico-chemical and sensory properties of YAs. YAs were made by emulsifying anhydrous milk fat (AMF) or coconut oil in milk and lupin protein suspensions. The starters used, in mono- and cocultures, were the strains Lactococcus lactis NCDO2125, Enteroccocus faecalis CIRM-BIA2412 and Lactiplantibacillus plantarum CIRM-BIA1524. Textural properties and metabolites of YAs were evaluated and their sensory properties compared using a sorting task. Some cocultures led to higher firmness, viscosity, and water holding capacity of YAs, compared to monocultures. AMF and a milk:lupin protein ratio of 67:33 gave firmer and more viscous YAs. YAs were sensorially discriminated on the basis of protein ratio and fat type, but not of starters. The cocultures exhibited more diverse functional outputs, such as texturing, production of flavour compounds, proteolysis, when the strains associated in coculture had distinct capacities. Appropriate associations of LAB and formulation offer interesting solutions to improve the perception of YAs, and ultimately, encourage their consumption.

Structural and Vibrational Investigations of Mixtures of Cocoa Butter (CB), Cocoa Butter Equivalent (CBE) and Anhydrous Milk Fat (AMF) to Understand Bloom Chocolate Process

Structural and Vibrational Investigations of Mixtures of Cocoa Butter (CB), Cocoa Butter Equivalent (CBE) and Anhydrous Milk Fat (AMF) to Understand Bloom Chocolate Process

The rheology and foamability of crystal-melt suspensions composed of triacylglycerols.

The rheology of triacylglycerol (TAG) crystal-melt suspensions (CMSs) consisting of anhydrous milk fat (AMF), cocoa butter (CB), and palm kernel oil (PKO) as function of crystallization shear rate cryst and crystal volume fraction ΦSFC is investigated by in-line ultrasound velocity profiling – pressure difference (UVP-PD) rheometry. Measurements up to ΦSFC = 8.8% are presented. Below the percolation threshold Φc, no yield stress τ0 is observed and the viscosity η scales linearly with ΦSFC. Above Φc, a non-linear dependency of both τ0 and η as function of ΦSFC is apparent. For AMF and CB, the increase in cryst leads to a decrease in η and τ0 as function of ΦSFC, whereas for PKO based CMSs the opposite is the case. Scanning electron microscopy (SEM) and polarized light microscopy (PLM) relate these rheological findings to the microstructure of the investigated CMSs by taking the effective aspect ratio aeff and the concept of the effective crystal volume fraction ΦeffSFC into account. Foam formation by dynamically enhanced membrane foaming (DEMF) is performed directly after crystallization and reveals that depending on the CMS rheology and crystallite-, crystallite cluster- and crystal floc microstructure, a wide range of gas volume fractions between 0.05–0.6 are achievable.

Ultrasound Characterisation of the Rheology of Crystallising Anhydrous Milk Fat

Ultrasound Characterisation of the Rheology of Crystallising Anhydrous Milk Fat

Dietary fats modulate neuroinflammation in mucin 2 knock out mice model of spontaneous colitis

Specific diets regulate neuroimmune responses and modify risk of inflammatory bowel diseases, including ulcerative colitis. A link between gut and brain inflammation is also emerging. We hypothesized that adjusting dietary fatty acid composition modulates the neuroimmune responses in the mucin 2 knock out mice model of spontaneous colitis. Mice were randomly divided into three groups and fed isocaloric diets that only differed in their fatty acid composition. Diets enriched with anhydrous milk fat, corn oil, or Mediterranean diet fats were used. After nine weeks, brain and serum concentrations of ten inflammatory cytokines were measured. Three of these cytokines, including interleukin (IL)-2, IL-12 p70 and interferon-γ, were differentially expressed in the brains of animals from the three diet groups while there were no differences in the serum concentrations of these cytokines. Since only limited information is available about the functions of IL-2 in the central nervous system, in vitro experiments were performed to assess its effects on microglia. IL-2 had no effect on the secretion of neurotoxins and nitric oxide by microglia-like cells, but it selectively regulated phagocytic activity and reactive oxygen species production by stimulated microglia-like cells. Modulation of microglial reactive oxygen species through altered brain IL-2 concentrations could be one of the mechanisms linking diets with modified risk of neuroimmune disorders including Parkinson's disease.

Crystallization of emulsified anhydrous milk fat: The role of confinement and of minor compounds. A DSC study

We examined the crystallization and melting of anhydrous milk fat (AMF)-in-water emulsions stabilized by sodium caseinate. Various additives at low concentrations (<5 wt%), differing in their hydrocarbon chain length (propionic vs. palmitic acid), unsaturation (palmitic vs. oleic acid), and esterification state (palmitic acid vs. tripalmitin) were used to modulate AMF crystallization kinetics. Three emulsions with different average droplet diameters were cooled down from 60 °C to 4 °C. Fat crystallization was followed by DSC under dynamic (cooling) and static (isothermal) conditions. Propionic acid did not have any noticeable effect. Oleic acid favored supercooling and the formation of unstable polymorphs at short times but its impact faded after 48 h of isothermal storage. The impact of palmitic acid was related to its amphiphilic properties and vanished after 48 h. Tripalmitin influenced crystallization via volume effects that were persistent. It formed mixed crystals which extended the melting range of AMF.

Modified milk fat as encapsulating material for the probiotic microorganism Lactobacillus acidophilus LA3

The potential of modified anhydrous milk fat as an encapsulating material for Lactobacillus acidophilus LA3 was evaluated. An emulsion containing L. acidophilus and lecithin was prepared and atomised in a spray cooling chamber. Viable cells were enumerated and the microparticles were stabilised at 5 °C for 24 h, then characterised and stored at −18, 5 and 25 °C for 60 days. The manufacturing process did not affect cell viability. Encapsulated L. acidophilus showed high viability after 60 days of storage. The lower the temperature, the lower the liquid fat content, resulting in microparticles with the appearance of a dry, fine and dispersed powder. In contrast, the microparticles stored at 25 °C had a granular appearance and little dispersion due to higher liquid fat content. The physical stability of microparticles and their ability to maintain the viability of microorganisms suggest their effective use in different food matrixes.