Ultrasonic Treatment Time Research Articles

Influence of mycelial integrity damaged by ultrasonic treatment on product textural properties and in vitro digestibility

This study investigated the effects of ultrasonic treatment with different intensities (200, 400, and 600 W) and durations (15, 30, and 45 min) on the mycelial integrity, product quality, and in-vitro digestibility of mycoprotein. Results showed that the mycelium was damaged to varying degrees under different ultrasonic parameters. The mycelium showed obvious damage when the time of ultrasonic treatment lasted more than 30 min or the power exceeded 400 W. As a result, the particle size, hardness and chewiness of mycoprotein products were decreased significantly. Compared with the control group (CK), ultrasonic treatment increased the proportion of immobile water and changed the secondary structure of the fungal intracellular protein, which may be the reason for improving in-vitro digestibility of mycoprotein products. This result demonstrated that, by damaging the mycelial integrity and changing the protein secondary structure, ultrasound treatment could decrease the texture characteristics, but improve the water-holding capacity and in-vitro digestibility of products. This study would provide a potential application for the minced meat products by mycoprotein treated with ultrasound.

Ultrasonic depolymerization of pomegranate peel pectin: Effect of sonication time on antioxidant, α-amylase inhibitory, and prebiotic properties

This study aimed to investigate the effects of ultrasonic treatment time (5–30 min) on the structural characteristics, antioxidant, α-amylase inhibitory, and prebiotic properties of pomegranate peel pectin (PPP). The extracted PPP was rich in galacturonic acid (64.27 %) and exhibited a high degree of esterification (DE, 61.7 %), with an average molecular weight (Mw) of 135.6 kDa. The Mw, particle size, and DE of ultrasonic-treated PPPs (U-PPPs) significantly decreased compared to the PPP. FTIR analysis revealed that the intensity of the peak at ~1730–1720 cm−1 weakened with prolonged treatment time. The total phenol content, antioxidant activity, and α-amylase inhibition of U-PPPs were enhanced compared to PPP. Both PPP and U-PPP treated for 30 min promoted the growth of Bifidobacterium longum and Lactobacillus casei, with U-PPP-30 showing a greater preference over PPP and inulin. In conclusion, ultrasonic treatment represents a promising approach to depolymerization aimed at enhancing the biological activities of pectin.

Ultrasonic-assisted preparation of SBS modified asphalt: Cavitation bubble numerical simulation and rheological properties

SBS (styrene–butadiene–styrene block copolymer) is currently the most widely used asphalt modifier, and SBS modified asphalt is usually prepared by high-speed shearing. This paper combines the cavitation effect of ultrasonic to assist in the preparation of SBS modified asphalt, and conducts numerical simulation and rheological properties research on the cavitation bubbles in the molten SBS modified asphalt fluid. The cavitation bubbles in the modified asphalt fluid will expand and contract as the pressure changes inside and outside the bubbles. When the cavitation bubble is compressed to the minimum and the pressure inside the bubble reaches 1.94 × 105Pa, the direction of the velocity vector near the cavitation bubble will change with the expansion and compression of the bubble. The expansion–contraction process of a single cavitation bubble can release 6.41 × 10-7J of energy, thus breaking the long bonds in asphalt and generating a large number of free radicals react with the unsaturated C = C bonds in the SBS molecules. According to the preparation process of modified asphalt, the influence of ultrasonic wave on rheological property of modified asphalt was studied through experiments. The results show that ultrasonic treatment can enhance the elasticity of asphalt and improve the temperature sensitivity of asphalt. With the increase of ultrasonic treatment time, the anti-rutting deformation ability of SBS modified asphalt is greatly improved. At the same temperature, the recovery rate of asphalt also increases with the increase of ultrasonic treatment time, and the non-recoverable compliance (Jnr) decreases Combined with the numerical simulation of cavitation bubbles, the ultrasonic process is added to asphalt production, which is of great significance for the green production of modified asphalt and the improvement of the rheological properties of modified asphalt.

Improved carbon fibers dispersion in geopolymer composites

Carbon fibers (CFs) reinforced alkali-activated (AA) ground granulated blast furnace slag (GGBFS) geopolymer composites have excellent mechanical and thermoelectrical properties, as well as low energy consumption and low CO2 emissions during their production. However, the dispersion of CFs in the geopolymer matrix is always a technical issue in the preparation of the green composite material. Therefore, this study comparatively investigated various dispersion methods, including, mixing sequence (pre-mixing and after-mixing methods), dispersing agent (nano silicon dioxide [nSiO2]), and ultrasonic treatment time (0, 15, 30, and 45 min), as well as CFs content (0.5, 1.0, and 1.5 wt% of GGBFS). The distribution of CFs was then qualitatively and quantitatively evaluated by a series of tests, such as flowability, electrical resistivity, flexural strength, scanning electron microscope (SEM) analysis, and X-ray computed tomography (CT). The experimental results showed that the proposed pre-mixing method provided excellent dispersion characteristics for CFs compared with the after-mixing method. The introduction of nSiO2 can enhance the dispersion of CFs and the mechanical and electrical properties of AA GGBFS geopolymer composites. At a carbon fiber content of 1.5 %, the pre-mixing method and the addition of nSiO2 dispersant reduced the resistivity of the 28-day geopolymer composites by 17.0 % and 38 %, respectively, compared with the after-mixing method. It is feasible to use X-ray CT scanning with the gray-scale frequency map to analyze the dispersion effect of CFs in AA GGBFS geopolymer composites. However, the results were not intuitive when less agglomeration of CFs occurred for the low content of CFs. The scanning method is more applicable to the sample with over 1.0 wt% CFs. The average pixel areas of uniformly dispersed CF bundles in the 2D images of the pre-mixing method and the addition of nSiO2 dispersant specimens were 3.32 % and 6.55 % higher than those of the after-mixing method, respectively. The 2D and 3D scanning results from the dispersion characteristics of CFs were consistent. 2D scanning could provide a time-consuming option for the measurement of CFs dispersion characteristics.

Research note: Preparation and stability of egg white fluidic gel induced by ultrasonic pretreatment

Ultrasound-induced egg white fluidic gels (UEFG) were prepared through ultrasonic pretreatment followed by subsequent heating. The optimal preparation parameters for UEFG were: ultrasonic power density between 0.2 to 0.8 W/mL, ultrasonic treatment time surpassing 150 s, heating temperature within 70 to 76°C, and heating time under 16 min. The prepared UEFG is a milky white solution with a viscosity lower than that of fresh egg white, and displayed a particle size distribution primarily between 100 and 1,200 nm. Stability assessments conducted over 28 d at 4°C revealed that UEFG remained stable at pH 6-10, with exceptional stability from pH 8 to 10, while it is less stable in highly acidic (pH 2-4) or basic environments (pH 12). The UEFG also showed commendable stability in the presence of salt and sucrose solutions. We report a simple and novel method for preparing UEFG with good flowability after heating treatment. The UEFG has broad applications in the food industry, such as precooked egg white powder, high protein beverages, composite dairy products, etc.

Synthesis of kaliophilite by alkaline fusion and ultrasonic treatment method from kaolin raw material

Mexico has important kaolin deposits, which must be assessed to obtain products with a high commercial value, such as kaliophilite as raw material for biodiesel production. Two kaolins, A and B, with approximate SiO2:Al2O3 ratios of 1 and 1.2, respectively, were used as raw materials to produce kaliophilite. Both kaolins were obtained from the municipality of Agua Blanca in the State of Hidalgo, Mexico. Kaolins are a source of Al and Si for the synthesis of kaliophilite through an alkali fusion process at 700 °C followed by ultrasonic treatment at 28 kHz to different times and for Kaolin-KOH ratios of 1:1 and 1:1.2 (mass: mass). The kaolins as received and the alkaline mixtures heat and ultrasonically treated were analyzed using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS). The most suitable kaolin for synthesizing kaliophilite was kaolin A with the Si/Al mass ratio of approximately 1, which exhibited a higher crystallinity index range from 54 to 79.6%. Higher KOH concentrations promote the amorphous material formation decreasing the kaliophilite amount. The crystallinity index was increased when the time of ultrasonic treatment was increased.

Research on Ultrasonic Cavitation Treatment of Milk. An Experimental Approach

Homogenization is a standard milk processing method used to stabilize fat emulsions against gravitational separation. In the dairy industry, high-pressure homogenization is commonly applied, which requires significant energy input to achieve optimal processing conditions. The size and composition of fat globule membranes affect the sensory and rheological properties of secondary dairy products [1]. Recently, ultrasound has been frequently used for milk homogenization [2]. Unlike ultrasound, mechanical mixing does not provide emulsion stability even after prolonged treatment, highlighting the differences between these two technologies. These differences arise due to the varying degrees of fat globule and membrane disruption. However, dairy products with different physicochemical and functional properties can be produced using both ultrasonic treatment and in combination with other traditional homogenization methods.To study the impact of ultrasonic treatment parameters of milk, specifically their different values, on the size of fat inclusions and the stability of milk emulsion over a certain period after treatment.The study employed an experimental method of milk processing using an ultrasonic cavitation unit.The impact of ultrasonic cavitation on the quality of milk homogenization in a steady volume was investigated. Optimal process parameters, specifically the power of the ultrasonic field and treatment time, were experimentally determined. The use of ultrasonic frequency greater than 33 kHz was found to be impractical.It was experimentally proven that ultrasonic cavitation treatment of milk is extremely effective for obtaining homogeneous emulsions. Given that excessive heating (> 65 °C) is undesirable in the production of dairy products from a technological standpoint, a definite advantage of this method is the low-temperature (50 °C) mode compared to traditional processing methods (75–80 °C), which also positively affects the preservation of nutrients.

Effect of ultrasonication on the quality of amla pulp (Emblica officinalis): Optimization and comparison with the thermal processing

Amla pulp was treated with ultrasonication technique under the different set of designed conditions in order to optimize the ultrasonic conditions. A two factor four level Taguchi design was adopted to study the effect of ultrasonic intensity (180 – 717 W/cm2) and treatment time (4 – 16 min) on the ascorbic acid, naringin, total phenolic content, titratable acidity, total soluble solids, browning index, polymethylesterase and polyphenol oxidase activity of amla pulp. The optimal conditions were determined as ultrasonic intensity, 359 W/cm2 and treatment time, 12 min on the basis of S/N ratio analysis. Optimized ultrasonicated pulp was compared with the thermally treated pulp (90 °C/ 5 s) to observe the effect on quality parameters. Enzymatic activity reduced to a lower level at optimal ultrasonic processing conditions. Total phenolic content increased after ultrasonication treatment. LCMS of the optimized sample depicted the presence of compounds like ascorbic acid, corilagin, gallic acid, kaempferol, chebulagic acid and many more. Thermal treatment showed lower retention of bioactives and there were notable losses in ascorbic acid and total phenolic content. Browning index was also higher than control and ultrasonicated pulp sample. Microstructure of ultrasonicated sample showed damage to cells but thermal treated sample exhibited major cell damage.

Induced formation of nano precipitates and improve microstructure and mechanical properties by ultrasonic wave in the solid-liquid two-phase area of as-cast Ti48Al2Cr2Nb 2.5 C alloy

To refine the microstructure and form Ti3Al2 and C14 nano particles, and then improve strength and strain simultaneously, the Ti48Al2Cr2Nb 2.5 C alloy has been prepared under ultrasonic wave. Size of lamellar colony, lamellar spacing, phase composition, compressive properties and the related mechanisms have been studied. Results show that size of lamellar colony decreases from 40.7 to 33.0 µm and lamellar spacing decreases from 1.5 to 0.8 µm. Average length-diameter ratio of Ti2AlC decreases from 5.4 to 1.9 with increasing the ultrasonic treatment time from 20 to 100 s. Two kinds of nanoparticles form. One is hexagonal Ti3Al2 phase, which has incoherent relationship with γ phase. Another is Ti(Al, Cr)2 phase with C14 structure. The Ti2AlC and α grain are refined by undercooling nucleation and dendrite fragmentation in solid-liquid two-phase area. The active dislocations and vacancy under ultrasonic promote the diffusion of Ti and Cr, and then induce the Ti3Al2 and Ti(Al, Cr)2 formed during solid-phase transformation. Compressive results show that the strength increases from 1901 to 2532 MPa, and the strain simultaneously increases from 27 to 34% with increasing the time from 0 to 100 s. The lattice distortion caused by the difference in thermal expansion coefficient between the Ti3Al2, Ti(Al, Cr)2 and matrix and the microstructure refined by ultrasonic jointly hinder dislocation slip to strengthen the alloy. The refinement and uniform distribution of Ti2AlC hinder crack propagation to improve toughness.

Ultrasonic pretreatment for enhancing flotation separation of elemental sulfur and silver-bearing lead minerals from an oxidative pressure leaching residue of zinc sulfide

Ultrasonic pretreatment was introduced to enhance the flotation separation of elemental sulfur and silver-bearing lead minerals from an ultrafine residue produced by oxidative pressure leaching of zinc sulfide. The particle size analysis of residue shows that ultrasonic pretreatment increases the number of particles with high sulfur content in the −19 μm fraction. This resulted from the associated sulfur was effectively liberated from other minerals. The complete liberation proportions of elemental sulfur and plumbojarosite in residue are respectively increased by 20.91 % and 38.53 % after ultrasonic treatment, in terms of mineral liberation analysis (MLA). Time-of-flight secondary ion mass spectrometry (ToF-SIMS) investigation implies that the surface structure difference between elemental sulfur and silver-bearing lead minerals is expanded by ultrasonic pretreatment. As a result, the separation of sulfur and silver-bearing lead minerals is significantly improved by ultrasonic pretreatment. Under optimized conditions of ultrasonic power, ultrasonic treatment time and solid weight, pilot-scale flotation produced a concentrate that the sulfur grade and recovery of concentrate increased by 11.63 % and 9.10 %, respectively, and the lead and silver recoveries of tailings increased by 8.72 % and 9.50 %, respectively, compared with those obtained by using the flotation without pretreatment. This work may provide an important reference for effectively recycling complex secondary resources and reducing the difficulty of subsequent values extraction.

Stronger hierarchical filament prepared by orderly assembling of cellulose nanofibrils from wasted jute

TEMPO-oxidized cellulose nanofibrils (TOCNF) were prepared from wasted jute by TEMPO-mediated oxidation combined with short-time ultrasonic mechanical treatment. Then a simple and environmentally friendly wet-spinning technology was used to assemble TOCNF into hierarchical macroscopic filament. In order to analyze the influence of different TOCNF preparation processes directly, the properties of TOCNF suspensions and their effects on spun filaments were studied from the perspective of rheology. And on the basis of this, response surface analysis method was used to optimize the process parameters, the optimized process parameters were: the dosage of NaClO added in oxidation process, the oxidation reaction time and the ultrasonic treatment time of 5.33 mmol/g-cellulose, 68 min and 80 s, respectively. Under this preparation process, filaments with the tensile strength of 327.06 MPa were prepared. The spun filaments were straight and flexible, with fold structure on surface along the axis direction due to the orientation arrangement of TOCNF, which provided great potential for wide application and functional design.

Single Ultrasonic-Assisted Washing for Eco-Efficient Production of Mackerel (Auxis thazard) Surimi.

This study highlights a promising single washing method for producing dark-fleshed mackerel surimi aided by ultrasonication in conjunction with cold carbonated water containing 0.6% NaCl and mixed antioxidants (0.5% EDTA/0.2% sodium erythorbate/0.2% sodium tripolyphosphate) (CSA). Different washing periods (5, 10, and 15 min) with and without ultrasound were tested. Unwashed mince (A1) and conventional water-washed surimi (10 min/cycle, 3 cycles) (A2) were used as controls. A3, A4, and A5 were subjected to ultrasound-assisted washing for 5, 10, and 15 min, respectively, whereas A6, A7, and A8 had non-ultrasound-assisted washing for 5, 10, and 15 min. Results showed that the surimi yield decreased as the ultrasonic treatment time increased from 5 to 15 min (p < 0.05). Increased ultrasonic time resulted in greater protein denaturation, protein oxidation, myoglobin removal, and lipid oxidation in surimi (p < 0.05). Surimi produced by CSA ultrasonication for 5 min (A3), on the other hand, had a comparable overall quality to A2 surimi (p > 0.05). The correspondence gel (A3) outperformed the control gel (A2) in terms of gel strength, whiteness, and water-holding capacity (p < 0.05). The formation of regularly continuous, more organized, and smooth network structures in surimi gel was observed in A2 and A3 gels, whereas sparse and larger pore sizes were noticed in surimi gels produced by longer ultrasonic treatment. All of the surimi gels had identical FTIR spectra, indicating that the functional groups of the protein gel were consistent throughout. As a result, a single 5 min CSA-ultrasonic washing could potentially yield surimi of comparable quality to conventional washing. This could pave the way for the development of dark-fleshed fish surimi, which would require less washing time and produce less waste water.

ОПРЕДЕЛЕНИЕ РЕЖИМОВ УЛЬТРАЗВУКОВОЙ КАВИТАЦИОННОЙ ОБРАБОТКИ МОТОРНОГО ТОПЛИВА

The article considers an example of ultrasonic cavitation created by a piezoelectric emitter. To identify the modes of ultrasonic cavitation treatment, the Qsonica sonicators Q-700 laboratory unit was used. The aim of the work is to determine the modes of ultrasonic treatment of motor fuel to create a cavitation region. Cavitation areas were determined by the area of destruction of aluminum foil samples, 0.008-0.009 mm thick. A sheet of aluminum foil was placed in the test medium parallel and perpendicular to the tip at different distances h, l. In order to identify the intensity of the resulting cavitation, cavitation noise was isolated from the signal of a hydrophone immersed in motor fuel at different distances from the radiator and connected to a multimeter model UT61E. The intensity of cavitation was estimated by the change in the resistance of the medium, R. The following types of motor fuel were used for processing: commercial diesel fuel, biodiesel based on ginger oil, mixed diesel fuel (containing 20% biodiesel). After the study, the foil was dried and the area of destruction was determined. It has been established that the following parameters influence the creation of cavitation – the distance from the radiating surface, intensity, amplitude and time of ultrasonic treatment of the sample.f= f (l, h, I, A, t). Four cavitation areas are defined: the area of active or optimal cavitation, the area of the beginning of cavitation, the area of incipient cavitation, the area of absence of cavitation. Depending on the amplitude and intensity, 6 operating modes are highlighted. It is established that the processing of the used motor fuel should be carried out on the 3 cavitation mode of operation (A =21-40%, I= 12.5-24.8 W / cm2) of the laboratory installation in the used technological volume or in larger volumes with reflective surfaces. It has been found that the cavitation noise in biodiesel is lower than in diesel fuel, since it is more viscous. In viscous liquids, cavitation is less developed and, consequently, the ultrasound absorption coefficient is lower for them. In this regard, it is necessary to design devices for media with a higher viscosity based on the optimal distance from the radiator to the bottom.

Effect of ultrasonic treatment on the quality of Mianning ham.

This paper investigates the optimal process for ultrasonic desalination of Mianning ham. The study analyzed various factors such as ultrasonic treatment time, temperature, and power to determine their impact on the rate of desalination of hams. A single factor test was conducted to study the rate of desalination. Further, A Box-Behnken experimental design was used to evaluate the effect of Mianning ham desalination. The design examined the impacts of ultrasound on the physicochemical properties, texture, and sensory of the ham. Response surface processing group underwent oral processing to determine the optimal ultrasonic treatment conditions with the highest acceptance level. The results show that the best conditions were: ultrasonic time 84.56 min, ultrasonic temperature 40.35°C, and ultrasonic power 150.85 W. The average desalination rate of the ham under the optimal conditions was 25.93% ± 0.69%, and the hardness was 4.48 N ± 0.62 N. Overall, this process significantly improved the desalination rate, texture, and sensory quality of Mianning ham, providing solid theoretical support for desalination processing at the back end of ham.

Intestine-targeted high internal phase Pickering emulsion formulated using silkworm pupa protein via ultrasonic treatment

High internal phase Pickering emulsions (HIPPEs) stabilized by food grade particles have received much attention as deliver vehicles for bioactives in recent years. In this study, ultrasonic treatment was conducted to regulate the size of silkworm pupa protein (SPP) particles, fabricating oil–in–water (O/W) HIPPEs with intestinal releasability. Briefly, the pretreated SPP and SPP-stabilized HIPPEs were characterized, and the targeting release was investigated using in vitro gastrointestinal simulations and sodium dodecyl sulfate–polyacrylamide gel electrophoresis. Results revealed ultrasonic treatment time was the key factor regulating emulsification performance and stability of HIPPEs. Optimized SPP particles were obtained based on their size and zeta potential of 152.67 nm and 26.77 mV, respectively. With ultrasonic treatment, the hydrophobic groups in the secondary structure of SPP were exposed, facilitating the formation of a stable oil–water interface for HIPPEs. Additionally, SPP-stabilized HIPPE showed high stable against the gastric digestion. The SPP with 70 kDa molecular weight, which was the major interfacial proteins of the HIPPE, can be hydrolyzed by intestinal digestive enzymes, enabling the intestine-targeted release of the emulsion. Overall, in the present study, a facile method was developed to stabilize HIPPEs using solo SPP with ultrasonic treatment to protect and deliver hydrophobic bioactive ingredients.

Effects of low-intensity ultrasound on anammox granular sludge

Low-intensity ultrasound can effectively shorten the start-up time of the anaerobic ammonia oxidation process and improve nitrogen removal performance. However, the effect of low-intensity ultrasound on the anammox granular sludge structure and the functional bacteria metabolism is still unclear. Herein, the effects of ultrasonic irradiation with different ultrasonic power densities and treatment times on nitrogen removal performance and anammox granular sludge structure were studied. The activity of anammox granular sludge increased by 20.81 % after irradiation (0.2 W/mL ultrasonic power density, 2 min treatment time). When further increased to 0.3 W/mL or 4 min, respectively, sludge activity was inhibited. Under optimal ultrasound parameters, the activity of Nar, NirS, and HZO was increased by 43.98 %, 17.92 %, and 16.49 %, respectively, and the cell membranes permeability was improved. Extracellular polymers and cell cluster shedding improved the mass transfer performance. Excessive ultrasonic energy lead to cell membrane damage or cell rupture.

Ultrasonication for preparing high-performance phase change material nano-emulsions: Optimization and characterization

This work was aimed to optimize the formulation of phase change material nano-emulsions by ultrasonic emulsification that has not been investigated systematically. The optimization was performed using response surface methodology on two response parameters, average droplet size and apparent viscosity, and three independent variables including ultrasonic amplitude (X1), treatment time (X2), and surfactant content (X3). The significance of three variables on both droplet size and apparent viscosity followed the order of X3 > X1 > X2. At the optimal variable levels (X1 = 58 %; X2 = 9 min; X3 = 8 wt%), the droplet size of 118.2 nm and apparent viscosity of 7.3 mPa·s were predicated by the regression model and also well verified by experiments. The 25 wt% phase change nano-emulsion formed by ultrasonication exhibited the best emulsion stability and the lowest apparent viscosity compared with those formulated by high-energy rotor-stator homogenizer and low-energy method of phase inversion temperature. In addition, the rheological behavior associated with the average droplet size and the solid/liquid state of phase change material was illustrated numerically for the first time. In general, a threshold of 170–180 nm was found for the transition of liquid-in-water emulsions from a shear-thinning non-Newtonian fluid to a Newtonian fluid in the shear rate range of 0.6–73 s−1. All solid-in-water suspensions showed shear-thinning fluid behavior, though the shear-thinning degree was dramatically reduced to a flow behavior index of about 0.95 as the particle size was below 100 nm. These findings may be useful for designing high-performance phase change material nano-emulsions with long service life, high energy storage capacity, and low pumping power consumption for applications.

Study on ultrasonic assisted extraction of polysaccharide from Angelica Dahurica

Taking Bozhou Angelica dahurica as the raw material, taking the polysaccharide yield as the evaluation index, the ultrasonic-assisted extraction of Angelica dahurica polysaccharide was studied. The effects of ultrasonic power, ultrasonic treatment time, solid-liquid ratio and temperature on the polysaccharide yield were investigated. Based on single factor experiment, the orthogonal experiment was carried out to optimize it. The results showed that the optimum technological conditions were as follows: solid-liquid ratio of 1:40, ultrasonic power of 500 W, ultrasonic time of 45 min, and the highest yield of Angelica dahurica polysaccharide was 15.8%. Ultrasonic time has a significant effect on the yield of Angelica dahurica polysaccharide. The ultrasonic power and the ratio of material to liquid have a significant effect, and the temperature has a low effect on polysaccharide extraction.

Influences of Ultrasonic Treatments on the Structure and Antioxidant Properties of Sugar Beet Pectin

The objective of this study was to explore the structural changes and oxidation resistance of ultrasonic degradation products of sugar beet pectin (SBP). The changes in the structures and antioxidant activity between SBP and its degradation products were compared. As the ultrasonic treatment time increased, the content of α-D-1,4-galacturonic acid (GalA) also increased, to 68.28%. In addition, the neutral sugar (NS) content, esterification degree (DE), particle size, intrinsic viscosity and viscosity-average molecular weight (MV) of the modified SBP decreased. Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) were used to study the degradation of the SBP structure after ultrasonication. After ultrasonic treatment, the DPPH and ABTS free radical scavenging activities of the modified SBP reached 67.84% and 54.67% at the concentration of 4 mg/mL, respectively, and the thermal stability of modified SBP was also improved. All of the results indicate that the ultrasonic technology is an environmentally friendly, simple, and effective strategy to improve the antioxidant capacity of SBP.

Properties of Potato Flour Films as Affected by Ultrasonic Treatment

AbstractThe properties of potato flour film‐forming dispersions treated with ultrasound and their resultant films are studied. The microscopic images show that ultrasonic treatment destroys the particles and improves the uniformity of film‐forming dispersions. The resultant potato flour film with ultrasonic treatment has a smoother surface and better transparency. As the ultrasonic power and treatment time increase, elongation at break reduces from 18.85% to 12.87%, while tensile strength increases at first and then decreases. Ultrasound decreases the water vapor transmission rate from 13.68 × 10−11 to 4.92 × 10−11 g−1 s−1 Pa−1 and increases the hydrophobicity of the films. Films with 15 min treatment show a lower water solubility index, while ultrasonic treatment for 45 min increases the solubility of films. The moisture content of treated films is higher than that of the untreated sample. Results show that ultrasonic treatment improves the properties of potato flour films.