Impact of ultrasonic treatment on rice starch and grain functional properties: A review

As a green, nonthermal, and innovative technology, ultrasonication generates acoustic cavitation in an aqueous medium, developing physical forces that affect the starch chemistry and rice grain characteristics. This review describes the current information on the effect of ultrasonication on the morphological, textural, and physicochemical properties of rice starch and grain. In a biphasic system, ultrasonication introduced fissures and cracks, which facilitated higher uptake of water and altered the rice starch characteristics impacting textural properties. In wholegrain rice, ultrasonic treatment stimulated the production of health-related metabolites, facilitated the higher uptake of micronutrient fortificants, and enhanced the palatability by softening the rice texture. This review provides insights into the future direction on the utilization of ultrasonication for the applications towards the improvement of rice functional properties.     

Isothermal and temperature-cycling retrogradation of high-amylose corn starch: Impact of sonication on its structural and retrogradation properties

In this study, the effects of sonication and temperature-cycled storage on the structural properties and resistant starch content of high-amylose corn starch were investigated. Sonication induced a partial depolymerization of the molecular structures of amylopectin and amylose. Sonication treatment induced the appropriate structural changes for retrogradation. Although the relative crystallinity of sonicated starch was lower than that of non-sonicated starch, sonicated starch after retrogradation showed much higher relative crystallinity than non-sonicated starch. Regardless of sonication treatment, temperature-cycled storage resulted in a higher degree of retrogradation than isothermal storage, but the rate of retrogradation was greater in sonicated starch than in non-sonicated starch, as supported by retrogradation enthalpy, the Avrami constant, and relative crystallinity. The highly developed crystalline structure in sonicated starches due to retrogradation was reflected by the large amount of resistant starch.     

DC conductivity and dielectric properties of maize starch/methylcellulose blend films

The transient current, electrical conductivity, dielectric constant (ε′), and dielectric loss factor (ε″) of starch and methylcellulose homopolymers and their blends with various compositions were studied under different conditions. The x-ray diffraction pattern was obtained for individual polymers and 50:50 wt/wt% blend sample to identify both the structure and degree of crystallinity. From transient current, the ionic and electronic transfer number as well as charge carrier density and drift mobility were determined. The values of activation energy in the temperature range 30–90 °C indicate that the conduction mechanism is due to combined electronic and ionic processes, while in the temperature range 100–160 °C, electronic contribution is predominant. The complex dielectric data of the present samples in an extended frequency and temperature range appear as different relaxation processes, which are connected with polymer dynamics.     

超声处理对ZnO薄膜光致发光特性的影响

对于结晶状态好的ZnO薄膜，测量了其光致发光(PL)光谱，发射光谱中只发现了峰值波长约389 nm的近紫外光.样品进行超声处理后，发射谱中不仅观察到近紫外峰，又观察到波长约508 nm的绿光峰.绿光峰的强度比近紫外光的强度强得多，且近紫外峰红移.进一步的热处理使绿光峰大大增强.超声处理改变了ZnO薄膜的质量和结晶状态，使晶格中产生氧空位.处理过程中的热效应使得薄膜晶格振动加剧.当晶格振动加剧到一定程度，晶格中的氧脱离格点形成氧空位.510 nm左右的绿色发光峰是ZnO晶体中的氧空位产生的.薄膜的温度越高， 关键词： ZnO薄膜 超声 光致发光     

Resistant starch type 2 from lotus stem: Ultrasonic effect on physical and nutraceutical properties

Resistant starch type 2 (RS) was isolated from lotus stem using enzymatic digestion method. The isolated RS was subjected to ultrasonication (US) at different sonication power (100–400 W). The US treated and untreated RS samples were characterized using dynamic light scattering (DLS), scanning electron microscopy (SEM), light microscopy and Fourier transform infrared spectroscopy (FT-IR). DLS revealed that particle size of RS decreased from 12.80 µm to 413.19 nm and zeta potential increased from −12.34 mV to −26.09 mV with the increase in sonication power. SEM revealed smaller, disintegrated and irregular shaped RS particles after ultrasonication. FT-IR showed the decreased the band intensity at 995 cm⁻¹ and 1047 cm⁻¹ signifying that US treatment decreased the crystallinity of RS and increased its amorphous character. The bile acid binding, anti-oxidant and pancreatic lipase inhibition activity of samples also increased significantly (p < 0.05) with the increase in sonication power. Increase in US power however increased the values of hydrolysis from 23.11 ± 1.09 to 36.06 ± 0.13% and gylcemic index from 52.39 ± 0.38 to 59.50 ± 0.11. Overall, the non-thermal process of ultrasonic treatment can be used to change the structural, morphological and nutraceutical profile of lotus stem resistant starch which can have great food and pharamaceutical applications.     

骨小梁材料特性对超声背散射信号的影响

基于时域有限差分法(FDTD)建立了松质骨的超声背散射仿真系统,研究了骨小梁材料特性对超声背散射信号的影响。首次得到松质骨中的超声背散射系数(BSC)和积分背散射系数(IBC)随骨小梁材料参数(密度、拉梅常数、黏度系数及声阻抗系数)的变化关系。研究结果表明,IBC随骨小梁密度的增加而增加;BSC和IBC随拉梅常数的增加而增加、随第一黏度系数的增加而近似线性地减小,第二黏度的变化对背散射信号的影响很小;背散射参数随阻抗系数的增加而减小。说明松质骨中的超声背散射特性不仅受骨矿密度(BMD)和骨微结构的影响,还与骨小梁的材料参数密切相关。研究结果有利于理解松质骨中超声的背散射特性,对松质骨骨质状况的评价有一定帮助。      

Effect of trabecular bone material properties on ultrasonic backscattering signals

In this study, ultrasonic backscattering signals in cancellous bones were obtained by finite difference time domain （FDTD） simulations, and the effect of trabecular material properties on these signals was analyzed. The backscatter coefficient （BSC） and integrated backscatter coefficient （IBC） were numerically investigated for varying trabecular bone material properties, including density, Lame coefficients, viscosities, and resistance coefficients. The results show that the BSC is a complex function of trabecular bone density, and the IBC increases as density increases. The BSC and IBC increase with the first and second Lame coefficients. While not very sensitive to the second viscosity of the trabeculae, the BSC and IBC decrease as the first viscosity and resistance coefficients increase. The results demonstrate that, in addition to bone mineral density （BMD） and microarchitecture, trabecular material properties significantly influence ultrasonic backseattering signals in cancellous bones. This research furthers the understanding of ultrasonic backscattering in cancellous bones and the characterization of cancellous bone status.     

聚合物物理属性对离子注入效应的影响

聚合物导电性能差, 表面电荷积聚所产生的电容效应致使其表面电位衰减, 采用等离子体浸没离子注入对其表面改性是非常困难的. 建立了绝缘材料等离子体浸没离子注入过程的粒子模拟(PIC)模型, 实时跟踪离子在等离子体鞘层中的运动形态及特性并进行统计分析. 并基于PIC模型, 将聚合物表面的二次电子发射系数直接与离子注入即时能量建立关联, 研究了聚合物厚度、介电常数和二次电子发射系数等物理量对鞘层演化、离子注入能量和剂量的影响规律. 研究结果表明: 当聚合物厚度小于200 μ m, 相对介电常数大于7, 二次电子发射系数小于0.5时, 离子注入剂量和高能离子所占的份额与导体离子注入情况相当. 通过对聚合物表面离子注入剂量和高能离子所占份额的研究, 为绝缘材料和半导体材料表面等离子体浸没离子注入的实现提供了理论和实验依据.     

Effect of ultrasonic treatment on the structure and functional properties of mantle proteins from scallops (Patinopecten yessoensis)

In this study, scallop mantle protein was treated by ultrasound at different powers, and then analyzed by ANS fluorescent probes, circular dichroism spectroscopy, endogenous fluorescence spectrum, DNTB colorimetry and in-vitro digestion model to elucidate the structure–function relationship. The results indicated that ultrasound can significantly affect the secondary structure of scallop mantle protein like enhancing hydrophobicity, lowering the particle size, increasing the relative contents of α-helix and decreasing contents of β-pleated sheet, β-turn and random coil, as well as altering intrinsic fluorescence intensity with blue shift of maximum fluorescence peak. But ultrasound had no effect on its primary structure. Moreover, the functions of scallop mantle protein were regulated by modifying its structures by ultrasound. Specifically, the protein had the highest performance in foaming property and in-vitro digestibility under ultrasonic power of 100 W, oil binding capacity under 100 W, water binding capacity under 300 W, solubility and emulsification capacity under 400 W, and emulsion stability under 600 W. These results prove ultrasonic treatment has the potential to effectively improve functional properties and quality of scallop mantle protein, benefiting in comprehensive utilization of scallop mantles.     

Measurement of physical properties in liquids under high pressure by ultrasonic technique

Abstract

A new versatile apparatus based on the falling body viscometer principle is presented. An ultrasonic technique has been developped to record continuously the plunger position. Compared to similar experiments, our device presents many improvements which are discussed and illustrated by recent results.     

Effect of ultrasonic treatment on the morphology of casein particles

In this study, the effect of ultrasonic treatment duration on the morphology of self-assembled casein particles was investigated by atomic force microscopy (AFM), low vacuum scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In the case of AFM images, the particle analysis which was carried out by the SPIP program showed that the self-assembled casein particles after being ultrasonically treated for 2 min got smaller in size compared to the casein particles that have not been exposed to any ultrasonic treatment. Surprisingly, however, increasing the ultrasonic time exposure of the particles resulted in an opposite effect where larger particles or aggregates seemed to be present. We show that by comparing the results obtained by AFM, SEM and TEM, the information extracted from the AFM images and analyzed by SPIP program give more detailed insights into particle sizes and morphology at the molecular level compared to SEM and TEM images, respectively.     

Effects of ultrasound treatment on the starch properties and oil absorption of potato chips

As a non-thermal processing method, the ultrasound treatment prior to the frying process has been demonstrated with great potential in reducing the oil absorption of fried food. This research aimed to evaluate the effect of ultrasound pretreatment on starch properties, water status, pore characteristics, and the oil absorption of potato slices. Ultrasound probe set with two power (360 W and 600 W) at the frequency of 20 kHz for 60 min was applied to perform the pretreatments. The results showed that ultrasound pretreatment led to the surface erosion of starch granules and higher power made the structure of starch disorganized. Moreover, the fraction of bound water and immobilized water were changed after ultrasonic pretreatment. Pores with the minor diameters (0.4–3 μm and 7–12 μm) were formed after ultrasound pretreatment. The penetrated surface oil (PSO) content, and structure oil (STO) content were reduced by 27.31% and 22.25% respectively with lower power ultrasound pretreatment. As the ultrasound power increased, the surface oil (SO) content and PSO content increased by 25.34% and 12.89% respectively, while STO content decreased by 38.05%. By using ultrasonic prior to frying, the quality of potato chips has been greatly improved.     

Effects of ultrasonic treatment on ovomucin: Structure,functional properties and bioactivity

The effects of ultrasonic treatment on the structure, functional properties and bioactivity of Ovomucin (OVM) were investigated in this study. Ultrasonic treatment could significantly enhance OVM solubility without destroying protein molecules. The secondary structure changes, including β-sheet reduction and random coil increase, indicate more disorder in OVM structure. After ultrasonic treatment, the OVM molecule was unfolded partially, resulting in the exposure of hydrophobic regions. The changes in OVM molecules led to an increase in intrinsic fluorescence and surface hydrophobicity. By detecting the particle size of protein solution, it was confirmed that ultrasonic treatment disassembled the OVM aggregations causing a smaller particle size. Field emission scanning electron microscopy (FE-SEM) images showed that ultrasonic cavitation significantly reduced the tendency of OVM to form stacked lamellar structure. Those changes in structure resulted in the improvement of foaming, emulsification and antioxidant capacity of OVM. Meanwhile, the detection results of ELISA showed that ultrasonic treatment did not change the biological activity of OVM. These results suggested that the relatively gentle ultrasound treatment could be utilized as a potential approach to modify OVM for property improvement.     

Effect of ultrasonic treatment on heavy metal decontamination in milk

Ultrasound has been found useful in increasing the efficiency and consumer safety in food processing. Removal of heavy metal (lead, mercury, and arsenic) contamination in milk is extremely important in regions of poor ecological environment – urban areas with heavy motor traffic or well established metallurgical/cement industry. In this communication, we report on the preliminary studies on the application of low frequency (20 kHz) ultrasound for heavy metal decontamination of milk without affecting its physical, chemical, and microbiological properties.     

Effects of ultrasonication on the properties of maize starch/stearic acid/ sodium carboxymethyl cellulose composite film

Ultrasonic treatment can improve the compatibility between a hydrophobic material and a hydrophilic polymer. The light transmittance, crystalline structure, microstructure, surface morphology, moisture barrier, and mechanical properties of a composite film with or without ultrasonication were investigated. Ultrasound increases the film’s light transmittance, resulting in a film that has good transparency. Ultrasonication did not change the crystalline structure of the polymer film, but promoted V-type complex formation. The surface of the film became smooth and homogeneous after the film-form suspension underwent ultrasonic treatment. Compared to the control film, after ultrasonication at 70% amplitude with a duration of 30 min, the average roughness and maximum roughness declined from 212 nm to 17.6 nm and from 768.7 nm to 86.5 nm, respectively. The composite film with ultrasonication exhibited better tensile and moisture barrier properties than the nonsonicated film. However, long-term and strong ultrasonication will destroy the polymer structure to some extent.     

Physiochemical properties of digested sewage sludge with ultrasonic treatment

We investigated the dewaterability and physiochemical properties of digested sludge after treatment with ultrasonic energy for the purpose of reducing sludge. The study involved laboratory experimentation under varying test conditions of treatment time, volume of sludge and ultrasonic energy, which combined can be denoted as specific supplied energy (E(v)). Results of the experiments show that particle size (dp(50), dp(10), U) of the ultrasonically treated sludge decreases due to the separation of sludge flocs. Capillary suction times (CSTs) decrease significantly, while turbidity, VDSs/VS and SCODs/TCOD increase with ultrasonic treatment. From these results, it was found that the ultrasonic treatment specified by the supplied energy (E(v)) can not only improve dewaterability but also reduce the volume and mass and change the chemical properties of sludge.     

Effect of ultrasonic separation on the structure and properties of diallyl phthalate prepolymer

The bulk polymerization of diallyl phthalate (DAP) was carried out at high temperature (190 degrees C) without using any initiator, and the reaction was stopped before the gelation point in order to get the prepolymer of DAP. The mixture for the prepolymer and the monomer was successfully separated by a novel ultrasonic method for the first time, and the separation efficiency for the new method was obviously higher than that for the traditional reprecipitation. The product obtained by ultrasonic separation was characterized by infrared spectroscopy (IR), gel permeation chromatography (GPC) and iodine number measurement. It was shown that the average molecular weight of the prepolymer got by the ultrasonic method was lower than that of the prepolymer got by the multi-precipitation, moreover, the molecular weight distribution of the prepolymer got by the ultrasonic separation was broader. Besides, the residual unsaturation degree of the prepolymer separated by ultrasonic was slightly higher than that of prepolymer separated by reprecipitation.     

Optimization of acoustic parameters for ultrasonic separation of emulsions with different physical properties

Ultrasound is an emerging and promising method for demulsification, which is highly affected by acoustic parameters and emulsion properties. Herein, a series of microscopic and dehydration experiments are carried out to investigate the parameter optimization of ultrasonic separation. The results show that the optimal acoustic parameters highly depend on the emulsion properties. For low frequency ultrasonic standing waves (USWs), mechanical vibrations not only facilitate droplet collision and coalescence, but also disperse the surfactant absorbed on the interface to decrease the interfacial strength. Therefore, low frequency ultrasound is suitable for separating emulsions with high viscosity and high interfacial strength. Increasing the energy density to produce moderate cavitation can increase demulsification efficiency. However, excessive cavitation results in secondary emulsification. In high frequency USWs, the droplets migrate directionally and form bandings, thereby promoting droplet coalescence. Therefore, high frequency ultrasound is favorable for separating emulsions with low dispersed phase content and small droplet size. Increasing the energy density can accelerate the aggregation of droplets, however, excessive energy density causes acoustic streaming that disturbs the aggregated droplets, resulting in reduced demulsification efficiency. This work presents rules for acoustic parameter optimization, further advancing industrial applications of ultrasonic separation.     

Effect of manganese on certain physical properties of Fe-Ni invars

The effect of manganese on the Curie point, elastic properties and magnetostriction of Fe-Ni invars was studied. It was established that manganese suppresses the invar anomaly of these alloys. Non-uniform distribution of manganese in the austenite spreads the ferromagnetic transformation.Translated from Izvestiya Vysshykh Uchebnykh Zavedenii, Fizika, No. 10, pp. 57–62 (1972).