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Three oleogeletors molecules (Triacontane (TC), Stearic acid (SA), and Behenyl Lignocerate (BL)) were studied individually, in pairs, or all together to make an oleogel using triolein as the oil. WAXS, SAXS and USAXS were used to elucidate the solid structures from angstroms to a few micrometers. A two-dimensional mapping of atomic positions for each molecule was carried out to understand the crystalline multilayer structures formed. We assumed that the molecules were rigidly extended and that they underwent no significant (hindered) rotations so that the free energy is determined by the Lennard-Jones interactions of closely-packed multilayers. TC molecules were predicted to form a tilt angle of θ ≈ 33°, yielding a SAXS line at q≈ 0.194 Å, in acceptable agreement with the measured q=0.181 Å.For SA crystals θ ≈ 33° (predicted) yielding a SAXS line at q=0.150 Å compared to q=0.159 Å (observed). No mixed crystals were observed for any pair of molecules or when all three were used. USAXS data showed that SA forms large nanocrystals compared to TC and BL. All three combinations of molecular pairs showed basic scatterers smaller or similar to those of individual molecules. The theory presented here, together with the experimental results, showed why no mixed crystals are formed from two or all three molecules. Data from the USAXS region suggested that, when using all three molecules, a more compact fractal structure was obtained, compared with those if one or two of the molecules were used.

Oleogelators are molecules that, when combined with edible oils can form semi-solid materials. Although many molecules have been tried as oleogelators in the last 20 years, much is still unknown. Here, the molecular structure of two possible oleogelators: triacontane (TC) and behenyl lignocerate (BL) were studied using a mathematical model for each molecule and carrying out computer simulation using the Metropolis Monte Carlo (MMC) algorithm in which the only interaction is via Lennard-Jones dispersion forces. The computer simulation explored the possibility of having either rigidly-extended molecules or twisted ones via the formation of gauche bonds. The results showed that both TL and BL molecules create a monolayer that did not include any gauche bond so that all molecules were effectively rigidly extended. The effective thickness of the monolayer was compared with experimental data and with the predictions of Peyronel et al. (in review) which assumed that the molecules were rigidly-extended. The work reported here justified that assumption. The conclusion was that the TC and BL molecules must be packed with a tilt angle in relation to the methyl group plane to match the experimental data. The angle of TC tilt was calculated to be ~27° which essentially confirms that reported by Peyronel et al. (in review).

In this study dairy phospholipid (PL) gels were made using 3 different concentrations of PL (15%, 30%, and 45%) and soybean oil to determine the gel-forming ability and functional traits that dairy PL have. After 24 h of storage the visual stability, crystal morphology, solid fat content, melting behavior, viscosity, and oil binding capacity of the gels were evaluated. All samples showed visual stability, whereas polarized light microscopy showed that high concentrations of PL reduced PL mobility, preventing tubular micelles from forming at high concentrations of PL (45%). Solid fat content increased with an increase in PL concentration. The melting enthalpy increased as the concentration of PL increased. The viscosity was assessed at 0.01, 0.1, and 1.0 1/s shear rates. A significant difference was observed between the 45% PL samples and the other samples at low and intermediate shear, but at high shear levels, a significant difference was only seen between the 15% PL sample and the other samples. The oil binding capacity showed a significant difference between the 45% PL sample and the other 2 samples. This study shows that dairy PL can be added to a vegetable oil to produce semi-solid material with appropriate functional properties.

The objectives of this study were to determine the influence of quality grade and internal temperature on the thermophysical properties of beef strip steaks. Beef strip loins (n=24) were collected from USDA Prime (PR), Low Choice(LC), and Standard (ST) carcasses. Strip loins were fabricated into 2.54 cm steaks at 21 d postmortem and randomly assigned to an internal temperature (4°C, 25°C, 55°C, 60°C, 71°C, 77°C). Steaks were subjected to various thermal and physical property measurements. No quality grade × internal temperature interaction was observed for diffusivity and conductivity (P > 0.05). Steaks tempered to 25°C had the greatest conductivity compared with all other internal temperature treatments (P = 0.021). A quality grade×internal temperature interaction was observed for center myosin and sarcoplasmic protein enthalpy values (P < 0.001). Raw (4°C and 25°C) ST steaks had lower enthalpy values compared with raw PR and LC steaks (P < 0.05). Raw steaks had greater surface myosin and both center and surface actin enthalpy values (P < 0.05). A quality grade × internal temperature was observed for surface and center viscoelasticity (P < 0.05). Raw steaks possessed less elastic behavior compared with cooked steaks, regardless of quality grade (P

Understanding the origins of the enhancement of crystallisation of a lipid (all-purpose shortening, APS) through the application of ultrasound is a fundamental pre-requisite for the exploitation of this technique in a wider context. To this end, we show here a number of measurements designed to probe the mechanisms responsible for this effect. For example, we show how the type of bubble cluster, produced at the sound source, alters the bubble population and residency time. In addition, to probe the various contributions to the enhanced crystallisation rate, isolation of the cluster environment below the piston like emitter (PLE) used as the ultrasonic source was shown to reduce the enhancement observed, but did not remove it entirely. This implied that the exposure of the liquid to pressure shocks and the environment around the cluster has a positive effect on the crystallisation kinetics. In turn the addition of extra seed crystals and mechanical agitation also enhances the rate of crystallisation. Finally, the time at which ultrasonic irradiation of the fluid is applied is shown to alter the kinetics observed. These observations suggest that two components are important: large bubble populations and mechanical effects on pre-existing crystals. These findings suggest that maximising these effects could be an eloquent way to enhance and control the material characteristics of materials produced in this manner.

The processing of healthy foods remains a challenge and any technology with the ability to tailor the physical properties of new materials is in demand. High-intensity ultrasound (HIU) has been identified as a useful processing technique for such activities particularly for edible lipids. HIU has been known to alter the crystallisation kinetics and in turn the resultant physicochemical properties for specific food applications. The role of cavitation dynamics during treatment of oils with HIU is of interest, with the knowledge gained allowing for insight into the complex and still undefined mechanism of action. To this end, the crystallisation kinetics of an edible lipid were investigated in the presence of several distinctly different cavitation conditions. Several cavitation clusters, including a bifurcated streamer (BiS), located on the surface of a piston-like emitter (PLE) were studied, each generated by a specific ultrasonic power level. Only samples crystallised at a low supercooling (ΔTSC) value display significant differences in induction time for each of the selected HIU powers, at least 5 minutes earlier than without exposure to HIU. Substantially better energy efficiencies were seen for the BiS regime (ΔTSC = 5 °C) which coincided with maximal crystal growth rates. An increase in melting enthalpy and elastic modulus is reported in the presence of HIU for all crystallisation temperatures, this effect is larger overall with increasing ultrasonic power. In addition, sonicated samples in the presence of the BiS event were composed of fewer smaller crystals compared to higher HIU powers after 60 minutes at 30 °C. Bubble dynamics recorded during a 10 s sonication period exhibited a greater acoustic attenuation effect for the highest ultrasonic power (75 W). The results suggest that the dynamics of the cluster and the presence of the BiS event are important in terms of energy efficiency and the physical properties of the crystallised lipid material.

Recent consumers' concerns about diet and its health benefits has triggered a reduction in consumption of foods rich in sugar, fat, salt, and chemical additives. As a result, an expanded market for functional foods has arisen. In particular, high-fat foods normally composed by saturated fatty acids, cholesterol and

The objective of this research was to evaluate if cavitation events generated during sonication (20 kHz, 216 μm amplitude, 10 s) are responsible for changes in physical properties of a fat with low levels of saturated fatty acids and if these changes are maintained during storage. The fat was crystallized at 24 and 34 °C and stored at 25 °C for up to 24 weeks. An increase in solid fat content and melting enthalpy was observed for sonicated samples crystallized at 34 °C and an increase in elasticity was observed for sonicated samples crystallized at 24 °C (P

The characterisation of bubbles or particles in an oil poses some unique challenges. In contrast to water solutions, the use of electrochemical detection approaches is more difficult in an oil. However, optical sensing systems have considerable potential in this area. Here we use a flow through channel approach and monitor the light propagation through this structure in an optical transmission sensor arrangement (OTS). This simple approach is demonstrated to be useful at detecting bubbles produced in the oil as a result of cavitation induced by high intensity ultrasound (HIU). The optical technique is shown to have an analytical basis. Bubble detection from an operating HIU source is shown to depend on position of the sensor with respect to the source. Critically, the bubble population can be followed for extended time periods after the ultrasonic source has been terminated. The detection of crystals is also demonstrated. Hence, this technique is ideal for the study of the effects of HIU on oils as they crystallise over extended time periods. This journal is

The aim of this research is to crystallize a low saturated interesterified soybean oil (IESBO) using a scraped surface heat exchanger (SSHE) combined with high intensity ultrasound (HIU). The SSHE operated at a flow rate of 3.125 mL/s, crystallization temperature of 32 °C, pressure of 2 bars, and barrels/pin worker speed of 344/208 rpm, respectively. HIU was applied at amplitudes between 20 and 80% using continuous, 5 s or 10 s pulses. The microstructure, melting behavior, rheology, hardness, and oil binding capacity (OBC) of the samples were evaluated. Non-sonicated sample resulted in a crystalline network characterized by 8.9 μm diameter crystals, elasticity values of 25,255Pa, hardness values of 1.3N and OBC values of 61%. Sonication using 50% amplitude for 5 s was the most efficient condition and resulted in a decrease in crystal size to 4.5 μm, an increase in elasticity values to 100,238Pa, and an increase in hardness and OBC values to 3.7N and 81.3%, respectively.

The objective of this study was to develop a numerical model to characterize wear behavior of solid fats with different crystalline networks. Wear behaviors of three different fats (cocoa butter [CB], anhydrous milk fat [AMF], and palm oil [PO]) crystallized at three temperatures (dependent on fat type) and two cooling rates (0.1 and 15 °C min−1) were evaluated under several normal forces (0.3–2.0 N) at room temperature (20 °C). A numerical model for penetration depth that accounted for both deformation and removal of material due to wear was developed. All models had mean absolute error

Highlights • Position where HIU should be applied is dependent on temperature and agitation. • At lower crystallization temperature, sample must be sonicated at HIU-1. • At higher crystallization temperature, sample must be sonicated at HIU-3. • HIU was able to improve fat physical properties such as G’ and OBC. • Better physical properties were obtained 20 °C under low agitation in position HIU-1., High-intensity ultrasound (HIU) has been used in the past to change fat crystallization and physical properties of fat crystalline networks. The objective of this work was to evaluate how HIU placed on different positions in a scraped surface heat exchanger (SSHE) using different processing conditions affect the physical properties of an interesterified palm olein. The sample was crystallized at two temperatures (20 °C and 25 °C) and two agitation rates (344/208 rpm and 185/71 rpm, barrels/pin worker). HIU (12.7 mm-diameter tip, 50% amplitude, 5 s pulses) was placed at three different positions within the SSHE. After processing, samples were stored at 25 °C for 48 h and analyzed according to the crystal morphology, solid fat content (SFC), oil binding capacity (OBC), melting behavior, viscoelasticity, and hardness. Physical properties were affected by crystallization conditions, by sonication, and by HIU position. The greatest improvement obtained was at 20 °C using low agitation when HIU was placed at the beginning of the SSHE. These conditions result in a sample with 98.9% of OBC, 274 kPa of viscoelasticity and 31 N of hardness. These results show that HIU can be used as an additional processing tool to improve physical properties of a palm-based fat and that the best improvement was obtained as a combination of crystallization conditions and HIU position.

The objective of this study was to determine the thermodynamic and physical properties of beef strip loin steaks of varying thicknesses and USDA quality grades cooked with high and low grill surface temperatures. Thermal characteristics described by changes in the denaturation temperature (between 55°C – 60°C) and enthalpies of protein denaturation (70°C – 75°C) both differed (P = 0.031 and P = 0.001, respectively) among thick steaks, with thick steaks cooked on a high grill surface temperature having a lower denaturation temperature and enthalpy compared with thick steaks cooked on a low grill surface temperature. No differences (P > 0.05) were observed among thin steaks for denaturation temperature or enthalpy. The elastic behaviors of the surface and center of the steaks were analyzed to determine how the microstructure of the beef responded to applied stress. The elastic behavior of steak centers was influenced in a three-way interaction (P = 0.029) between quality grade, steak thickness, and grill surface temperature. The elastic behavior of the surface of steaks was influenced by the interaction of quality grade and steak thickness (P = 0.031). These interactions, along with the differences in the thermal characteristic of proteins, suggest that the microstructure of steaks was affected by each cooking treatment group. Hardness, resilience, and chewiness were each influenced by a three-way interaction (P = 0.023; 0.014; and 0.030; respectively). Thin steaks possessed greater cohesiveness (P = 0.038) and shear force ( P = 0.007) values. Meanwhile, thin steaks exhibited lower springiness (P = 0.002). The measured alterations in thermal and physical proper- ties in the beef steaks suggest that the composition, thickness, and cooking regiments impact the microstructure of beef, and this was ultimately confirmed through textural measurements. The results of this research can be used in the design of cooking processes that match beef characteristics.

The present study was conducted to identify flavor-related chemical compounds and to elucidate beef flavor development in response to dry-aging. Paired grass-fed beef loins (n = 18) were obtained at 7 d postmortem, cut into two sections and assigned to 3 aging methods: conventional dry-aging (DA), vacuum packaged wet-aging (WA) and dry-aging in a bag (DW) for 28 days. Following aging, samples were analyzed for UPLC-MS metabolomics, volatile, fatty acid profiling, and consumer sensory comment analysis. Greater number of proteins and nucleotides derived metabolites were liberated in dry-aged samples compared to WA (P 0.05). In particular, the liberation of gammaglutmayl peptides and glutamine metabolites through the glutathione metabolism were identified. While fatty acid profile was not affected by treatments (P 0.05), higher concentrations of volatile compounds were found in the dry-aged (P 0.05). Dry-aging process decreased the presence of terpenoid and steroid lipid group, which could possibly result in reducing undesirable flavor of grass-fed beef.

The purpose of this study was to determine the effect of high-intensity ultrasound (HIU) on the physical properties of an all-purpose shortening and to evaluate how these properties changed during storage (48 hr; 4, 12, and 24 weeks) at 5 °C and 25 °C. Samples were crystallized at 30 °C for 60 min with and without the application of HIU (20 kHz; 3.2 mm-diameter tip, 168 µm amplitude, 10 s). After crystallization, physical properties, such as hardness, elasticity, melting behavior, and solid fat content (SFC), were measured. These properties were also measured during storage. The effect of HIU was significant in changing the SFC, hardness, G' and G'', melting enthalpy, and microstructure of the samples. After 60 min of crystallization, the sonicated samples had higher values of SFC, hardness, elasticity, and melting enthalpy than the ones obtained without sonication (P < 0.05). Changes in these physical properties were associated with the microstructure of the samples since sonication generated smaller, more uniformly sized crystals as well as increased the number of crystals. No differences were observed in the G' of the sonicated samples stored at 25 °C as a function of storage period. The G' of the nonsonicated samples increased until 12 weeks of storage and was maintained up to 24 weeks, suggesting that sonication speed up the formation of a stable crystalline network. Samples stored at 5 °C showed higher value in hardness, G' and G'', and SFC than the ones stored at 25 °C. PRACTICAL APPLICATION: High-intensity ultrasound (HIU) has been widely used as an additional tool to change the crystallization behavior in various lipids; however, the long-term storage effect of HIU has not been studied before. This research evaluates the effect of HIU on the physical properties of a palm-based shortening stored up to 24 weeks at two different temperatures (25 and 5 °C). The application of HIU may help increase the stability of lipid during storage.

The objective of this work was to evaluate the effect that agitation rate, crystallization temperature, and sonication have on the physical properties of a soybean-based fat with low levels of saturated fatty acids crystallized in a scraped surface heat exchanger (SSHE). The sample was crystallized at two temperatures (20 and 25 °C) and agitation rates (344/208 rpm in the barrels/pin worker-high agitation HA and 185/71 rpm barrels/pin worker-low agitation LA), and a constant flow of 11 L/hr. High-intensity ultrasound (HIU - 12.7 mm-diameter tip, 50% amplitude, 5 s pulses) was coupled to a water jacketed flow-cell and placed at three different positions within the SSHE. The combination of all those parameters affected samples' physical properties. Higher oil binding capacity (OBC) and elasticity (G') were obtained at 20 °C compared to 25 °C (77% vs. 63.78% for OBC and 30.4 kPa vs. 6 kPa for G', respectively) due to the smaller crystals formed at 20 °C. Fewer or no differences were observed due to agitation alone, but LA conditions allowed for more secondary nucleation to form due to sonication and resulted in a higher improvement on the properties of the fat. PRACTICAL APPLICATION: Fat crystallization in a scrapped surface heat exchanger (SSHE) combined with a high-intensity ultrasound (HIU) gives a realistic idea of how the HIU would work in an industrial line under continuous flow, shaved shear, and different supercooling. Results from this research will provide industry with tools on how and where to incorporate HIU in their processing line. Moreover, will give information on how to combined crystallization conditions and sonocrystallization in order to obtain improved physical properties.

The aim of this work was to evaluate how the physical properties of oleogels formulated with candelilla wax (CLX), monoglycerides (MG), and hardfat (HF) change with the addition of 1–30% water (w/w). Physical properties such as crystal microstructure, melting and rheological behavior, hardness, oil binding capacity, and thermal stability were evaluated. The oleogels evaluated in this study formed stable water-in-oil emulsion gels at 25 °C without the use of additional emulsifiers. The water addition in a range from 1 to 20% (w/w) resulted in a reduction in crystal size (Dm) from approximately 10 μm for the oleogel to less than 8 μm for the emulsion gels. This reduction in crystal size suggests that a well-organized crystalline network was formed in the emulsion gels resulting in improved physical properties. Emulsion gels with 1 to 20% (w/w) water showed a narrower melting profile, higher firmness, and lower oil loss compared to those of oleogel, and showed higher stability after temperature cycling at 40 °C. Samples with 1 and 5% w/w of water showed the best improvement in physical properties since they were 3 times harder than the respective oleogel with values of 0.42 N for the emulsions and 0.15 N for the oleogel. Also, the water addition increased G’ value from 4132.92 Pa for oleogel to 13157.78 Pa for emulsion with 1% water and 9702.35 Pa for emulsion with 5% water. The obtained results suggest that water amount up to 20% (w/w) can be added to oleogel to form stable emulsion gels.

This study aimed to determine the effect of high‐intensity ultrasound (HIU) on physical properties of soy protein isolate dispersions (SPI) and their addition to emulsion gels (EG) containing soybean oil (SBO), inulin (IN) and carrageenan (CAR). Sonicated and non‐sonicated SPI dispersions were mixed with CAR, IN and SBO and heated at 90 °C for 30 min to gel the emulsion. An increase in solubility and oil binding capacity was observed in sonicated SPI dispersions (S‐SPI) compared to the non‐sonicated ones. HIU changed the molecular weight of SPI and decreased apparent viscosity in the dispersions. The use of S‐SPI in the EG reduced the droplet size and increased the hardness and G′ values. The use of S‐SPI allowed a reduction of 75% of carrageenan in the EG without affecting the hardness of the gel. The results suggest that HIU can be used to improve rheological properties of functional EG.

Aging of cream is an important process to manage production time and to produce butter with consistent quality. The objective of this study was to evaluate the combined effect of temperature (5, 10, and 15°C) and agitation rate (0, 40, and 240 rpm) during aging of cream on the physical properties of cream and butter in a model system. Cream's solid fat content (SFC), melting behavior, and droplet size distribution were measured during and after 90 min of aging. Butter physical properties such as melting behavior, water content, and hardness were measured. The effects of agitation on SFC and droplet size are dependent on aging and churning temperature. Solid fat content increased faster at 5°C, and the maximum SFC was the highest at this temperature. An effect of agitation on SFC was observed only when cream was aged at 15°C. Agitating cream at 40 rpm increased the droplet size regardless of aging temperature. Two melting peaks, medium melting fraction (MMF) and high melting fraction (HMF), were found in cream samples aged at 5 and 10°C, but only a HMF melting peak was seen in the cream aged at 15°C. The enthalpy of MMF in the cream aged at 10°C with 40 rpm and without agitation was significantly lower than that in samples aged at 5°C regardless of agitation rate. Butter can be formed only from cream aged under certain conditions during 14.5 min of churning, which are 5°C with high agitation and 10°C regardless of agitation level. Butter produced with cream aged at 5°C with high agitation showed significantly higher MMF and total enthalpy values. However, no significant difference in enthalpy values was observed among the butter samples made from the cream aged at 10°C. Further crystallization of MMF occurred in the butter produced with cream aged at 10°C during 24 h of storage at 5°C, whereas no further crystallization occurred in the butter made with the cream aged at 5°C with high agitation. The hardest butter was obtained when cream was aged at 5°C with 240 rpm and at 10°C with 40 rpm. Softer butter was obtained when cream aged at 10°C with 240 rpm was used. This butter also had the highest water content. This study shows that butter hardness can be tailored by changing the aging conditions of the cream. Cream can be aged at higher temperature with low agitation without altering the hardness of butter. These results will help dairy producers to optimize butter making processes to obtain desired properties in the final product.