Effects Of High Intensity Ultrasound Research Articles

Emulsions Stabilized by Casein and Hyaluronic Acid: Effects of High Intensity Ultrasound on the Stability and Vitamin E Digestive Characteristics

Emulsions Stabilized by Casein and Hyaluronic Acid: Effects of High Intensity Ultrasound on the Stability and Vitamin E Digestive Characteristics

The Effects of High Intensity Ultrasound on Tropomyosin of Pacific Oyster (Crassostrea Gigas): Structure, Digestibility, and IgG Binding Capacity

The Effects of High Intensity Ultrasound on Tropomyosin of Pacific Oyster (Crassostrea Gigas): Structure, Digestibility, and IgG Binding Capacity

Effects of High-Intensity Ultrasound on the Microstructure and Mechanical Properties of 2195 Aluminum Ingots

The microstructural refinement of 2195 aluminum alloy ingots is particularly important for improving their industrial applications and mechanical properties. Combined with vacuum casting and inert gas protection, scalable high-strength ultrasonic melt processing (USMT) technology was used to manufacture 2195 aluminum alloy cylindrical ingots. Then, the influence of USMT on the main microstructural components (primary α-Al grains, secondary phase network, and precipitated particles) was studied. Our experiments show that the main microstructure of the ingot was improved after the introduction of ultrasound. Compared to the ingot formed without USMT, the size and morphology of the primary α-Al phase were optimized. The agglomeration of coarsening secondary phases can be alleviated, and the large layered secondary phase network becomes discontinuous throughout the ingot under USMT. At the same time, the mechanical properties of the solidified aluminum alloy ingots were also tested, and comparisons were made between samples formed with and without USMT. The results show that the stress concentration caused by the large area of coarse secondary phase in the ingot leads to the decrease of mechanical properties.

Effects of High Intensity Ultrasound on Physiochemical and Structural Properties of Goat Milk β-Lactoglobulin.

This study aimed to compare the effects of high intensity ultrasound (HIU) applied at various amplitudes (20~40%) and for different durations (1~10 min) on the physiochemical and structural properties of goat milk β-lactoglobulin. No significant change was observed in the protein electrophoretic patterns by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Deconvolution and second derivative of the Fourier transform infrared spectra (FTIR) showed that the percentage of β-sheet of goat milk β-lactoglobulin was significantly decreased while those of α-helix and random coils increased after HIU treatment The surface hydrophobicity index and intrinsic fluorescence intensity of samples was enhanced and increased with increasing HIU amplitude or time. Differential scanning calorimetry (DSC) results exhibited that HIU treatments improved the thermal stability of goat milk β-lactoglobulin. Transmission electron microscopy (TEM) of samples showed that the goat milk β-lactoglobulin microstructure had changed and it contained larger aggregates when compared with the untreated goat milk β-lactoglobulin sample. Data suggested that HIU treatments resulted in secondary and tertiary structural changes of goat milk β-lactoglobulin and improved its thermal stability.

High-Intensity Ultrasound Treatment on Soy Protein after Selectively Proteolyzing Glycinin Component: Physical, Structural, and Aggregation Properties.

In this study, a novel method called selective proteolysis was applied to the glycinin component of soy protein isolate (SPI), and a degraded glycinin hydrolysate (DGH) was obtained. The effects of high-intensity ultrasound (HIU) treatment (20 kHz at 400 W, 0, 5, 20, and 40 min) on the physical, structural, and aggregation properties of DGH were investigated with the aim to reveal the influence of the selectively hydrolyzing glycinin component on the HIU treatment of soy protein. The effects of HIU on DGH and a control SPI (CSPI) were both time-dependent. HIU induced the formation of soluble aggregates in both samples at an early stage, while it dissociated these newly formed aggregates after a longer duration. Selectively hydrolyzing glycinin contributed to the soluble aggregation by exposing the compact protein structure and producing small protein fractions. The larger extent of hydrophobic interactions and disulfide bonds imparted a higher stability to the soluble protein aggregates formed in DGH. As a result, DGH displayed more ordered secondary structures, a higher solubility, and better gelling properties after the HIU treatment, especially at 20 min. The results of this study will be beneficial to the scientific community as well as industrial application.

Effects of High-Intensity Ultrasound on Microstructure and Mechanical Property of In situ TiB2/2A14 Composites

In situ TiB2/2A14 composites with a 3% volume fraction were prepared by mixing salt reaction and high energy ultrasound. The effects of high-intensity ultrasonic on the microstructure and mechanical properties of TiB2/2A14 composites were systematically investigated. The microstructures of the composites were analyzed using scanning electron microscopy (SEM) and electron backscattered diffraction (EBSD). The phase composition was examined by X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). The results showed that after introducing ultrasonic vibration into the melt, due to the cavitation and acoustic streaming effect, the particle agglomerations were significantly reduced and particles of different sizes were evenly dispersed in the matrix. With ultrasonic vibration treatment of 120 s, the agglomerations were basically eliminated, and the particles were uniformly distributed to the most. The yield strength, tensile strength and elongation of the composites were increased by 53%, 21% and 30%, respectively, compared with that without ultrasonic vibration treatment (UVT).

Effect of high intensity ultrasound on physicochemical and functional properties of soybean glycinin at different ionic strengths

Abstract In this work, soybean glycinin was treated by high intensity ultrasound (HIU; 20 kHz at 80 W cm− 2 from 0 to 40 min) in three ionic strengths (I = 0.06, 0.2 and 0.6) at pH 7.0. At all three ionic strengths, HIU of glycinin increased emulsion stability and decreased the turbidity. However, the effects of HIU on the particle size, particle distribution, solubility, emulsifying activity index, and surface hydrophobicity showed different characteristics in three ionic strengths. For example, after HIU, surface hydrophobicity of glycinin increased at I = 0.06 and 0.2, but remained unchanged at I = 0.6. The effects of HIU on glycinin were more pronounced at I = 0.2 than the other two ionic strengths. Furthermore, HIU influenced the glycinin aggregates, but remained the secondary and tertiary structures almost unchanged, which could be demonstrated by circular dichroism and the intrinsic fluorescence spectra. Industrial relevance Soy protein is a plant protein which is widely employed in food products due to its high nutritional value, low price as well as its good functional properties. However, soy protein, especially glycinin, is easy to form aggregates and therefore limits soy proteins'application in some aspects. High intensity ultrasound (HIU) waves are generally considered as safe, non-toxic, and environmentally friendly. The results of this study suggested that HIU could dissociate soy glycinin and improve some functional properties of soybean glycinin, indicating that HIU can be considered as a potential tool to change soy glycinin's functional property. Moreover, this work found that the effects of HIU on physicochemical and functional properties of soybean glycinin were different in three ionic strengths, which could provide some fundamental information on how HIU influences the soy glycinin structures in different ionic strength and increase the application of HIU in the soy bean industry.

Determining the Effects of High Intensity Ultrasound on the Reduction of Microbes in Milk and Orange Juice Using Response Surface Methodology.

This study investigated the effects of high intensity ultrasound (temperature, amplitude, and time) on the inactivation of indigenous bacteria in pasteurized milk, Bacillus atrophaeus spores inoculated into sterile milk, and Saccharomyces cerevisiae inoculated into sterile orange juice using response surface methodology. The variables investigated were sonication temperature (range from 0 to 84°C), amplitude (range from 0 to 216 μm), and time (range from 0.17 to 5 min) on the response, log microbe reduction. Data were analyzed by statistical analysis system software and three models were developed, each for bacteria, spore, and yeast reduction. Regression analysis identified sonication temperature and amplitude to be significant variables on microbe reduction. Optimization of the inactivation of microbes was found to be at 84.8°C, 216 μm amplitude, and 5.8 min. In addition, the predicted log reductions of microbes at common processing conditions (72°C for 20 sec) using 216 μm amplitude were computed. The experimental responses for bacteria, spore, and yeast reductions fell within the predicted levels, confirming the accuracy of the models.

Effects of Ultrasonic Parameters on the Crystallization Behavior of Palm Oil

AbstractThe crystallization behavior of palm oil (PO) without and with the application of high‐intensity ultrasound (HIU) was investigated as the function of irradiation time (20, 60, 120, and 240 s), ultrasonic intensity (47.5, 95, 270, and 475 W) and temperature (20, 25, 30, and 36 °C). The effects on the crystallization behavior of PO were evaluated by ultraviolet/visible spectrophotometry, pulsed nuclear magnetic resonance and polarized light microscopy. Results indicated that all these parameters affected crystallization behavior. HIU significantly reduced the induction time and accelerated the crystallization rate at operating temperatures above 25 °C, but there was no significant difference at 20 °C due to high supercooling. The effects of HIU were more significant at higher power level and longer irradiation time, however, the thermal effect of ultrasound also increased with longer sonication time. The optimal sonication time was approximately 120 s which accelerated the crystallization rate of PO the most. The morphology studies suggested that HIU changed the growth mechanisms of crystals and generated smaller and uniformly crystals. At 36 °C, with extremely low supercooling condition, a combined effect was observed that prevented the separation of solid phase and liquid phase of the crystallized sample, and then led to a uniform distribution of crystals.

Comparative study of high intensity ultrasound effects on food proteins functionality

The objective of this work was to comparatively explore the impact of high intensity ultrasound (HIUS) on the functionality of some of the most used food proteins at the industrial level: whey protein concentrate (WPC), soy protein isolate (500E) and egg white protein (EW).10% w/w solutions at pH 6.5–7.1 were treated with HIUS for 20min, in an ultrasonic processor. The operating conditions were: 20kHz, 4.27±0.71W and 20% of amplitude.Before and after the HIUS treatment, the size of protein particles was measured by static light scattering. The amount of sulfhydryl groups was determined with Ellman’s reagent and the surface hydrophobicity by a fluorescence technique.The effects of HIUS on samples viscosity were determined. The evolution of the elastic (G′) and viscous (G″) moduli as well as tan δ were registered upon time and temperature in a controlled stress rheometer.In general, HIUS promoted a decrease in the consistency index of all protein solutions, mainly of soybean isolate. The gelation performance of EW was not modified by HIUS. However, WPC presented a higher elastic character, but 500E did not show changes upon heating, as it was already denatured before HIUS treatment. The size of aggregates suffered an overall reduction for WPC and 500E, but a slight increase for EW. Sulfhydryl content was unchanged for all proteins after HIUS application but surface hydrophobicity was greatly increased after treatment for all proteins. HIUS affected the studied functional properties differently depending on the size and nature of the protein. This technology could be used to obtain improved functional properties in some protein samples.

Tissue ultrasound absorption measurement with MRI calorimetry

The renewed interest in the use of high intensity focused ultrasound (US) for minimally invasive magnetic resonance imaging (MRI)-guided thermal therapy has stimulated a review of the interaction mechanisms of US with tissue. Although the study of tissue US properties has been conducted extensively, agreements on the measured values of tissue US absorption are poor. We propose a noninvasive approach to measure tissue US absorption based on a form of MRI calorimetry. US absorption is measured in a small tissue sample through a knowledge of the US intensity distribution incident on the tissue and an MRI measurement of total absorbed energy arising from US exposure. US absorption measurements were conducted at room temperature for ex-vivo bovine liver tissue at 1 MHz, which led to a measured US absorption coefficient of 0.058 Np/cm or 0.504 dB/cm. Because this approach is noninvasive, the experimental complications exhibited in earlier studies are not present. Furthermore, this approach can be applied over a range of frequencies, tissues, and temperatures, which will aid in understanding of biothermal effects of high intensity US to improve thermal therapy.

Some effects of high-intensity ultrasound on tobacco mosaic virus.

Some effects of high-intensity ultrasound on tobacco mosaic virus.