Ultrasonics Sonochemistry最新文献

The challenge of meat quality degradation due to transportation difficulties in high-altitude plateaus underscores the importance of an efficient thawing process for Tibetan pork to ensure its quality. This study compared four thawing methods ultrasound thawing (UT), refrigerator thawing (RT), hydrostatic thawing (HT), and microwave thawing (MT) to assess their impact on the quality of Tibetan pork, focusing on thawing loss, tenderness, color variation, and alterations in protein secondary structure and moisture content. Additionally, the study examined the impact of thawing on the metabolites of Tibetan pork using metabolomics techniques. The results indicated that UT yielded the highest quality samples. UT significantly accelerated the thawing rate and had minimal impact on tenderness compared to traditional thawing methods. Moreover, protein and lipid oxidation levels were reduced by UT treatment. Furthermore, it enhanced the binding capacity of protein and water molecules, reduced drip loss, and maintained meat color stability. What’s more, amino acid metabolites such as l-glutamic acid, l-proline, oxidized glutathione, and 1-methylhistidine played a significant role in thawing oxidation in Tibetan pork, exhibiting a positive correlation with protein oxidation. UT resulted in a notable decrease in the levels of hypoxanthine and 2-aminomethylpyrimidine, contributing to the reduction of bitterness in the thawed meat and consequently enhancing the freshness of Tibetan pork. This study offers novel insights into understanding the biological changes occurring during the thawing process, while also furnishing a theoretical framework and technical assistance to improve the quality of Tibetan pork and propel advancements in food processing technology.

Fried food products have low oil content with improved nutritional quality, higher crispiness, and better sensory attributes. Edible coatings can decrease the excessive oil uptake in deep-fat fried food products. Furthermore, ultrasound treatment before frying process decreased oil uptake of food products. So, in this study, the impact of gum edible coating and ultrasonic pretreatment (at two different power levels of 75 and 150 W) on the frying time of potato slices, and moisture percent, oil uptake, texture hardness, surface area change, color parameters (lightness, redness, yellowness, and total color change), and sensory attributes of fried potato slices were examined. Edible coating with basil seed gum (BSG) and ultrasonic pretreatment significantly increased the frying time of the slices (p < 0.05). The average moisture content of the fried slices changed from 49.48 % to 60.55 %, and was further increased by edible coating and ultrasonic treatment. The highest (26.92 %) and lowest (14.56 %) oil uptake were for the uncoated and coated-sonicated (150 W) fried potato slices, respectively. The ultrasound pretreatment significantly increased the hardness of fried potato slices (p < 0.05). The low and high intensity ultrasonic pretreatment (75 W and 150 W, respectively) significantly decreased the crust area change of fried potato slices (p < 0.05). The average lightness index of the fried samples changed from 63.30 to 71.58, and increased with increasing ultrasonic power. The minimum redness, yellowness, and total color change indexes were for the coated and high-power sonicated (150 W) samples, respectively. The highest appearance, odor, texture, flavor, and overall acceptance were for the coated and high-power sonicated (150 W) sample.

Whey protein is an important food ingredient, but it is also considered a major food allergen. The aim of this study was to investigate the effect of ultrasound pretreatment on the structure, IgE binding capacity, functional properties and biological activity of whey protein isolate (WPI) hydrolysates (WPH), including WPI hydrolyzed by a combination of enzymes from Bromelain and ProteAXH (BA-WPI) and WPI hydrolyzed by a combination of enzymes from Papain W-40 and ProteAXH (PA-WPI). The IgE binding capacity of BA-WPI and PA-WPI was reduced to 40.28% and 30.17%, respectively, due to disruption/exposure/shielding of conformational and linear epitopes. The IgE binding capacity of sonicated WPI was increased, but ultrasound pretreatment further reduced the IgE binding capacity of the hydrolysates to 32.89% and 28.04%. This is due to the fact that ultrasound pretreatment leads to conformational changes including increased α-helix and β-sheet structure, exposure of aromatic amino acids, surface hydrophobicity, and increased sulfhydryl content, which increases the accessibility of allergenic epitopes to WPI by the enzyme. Multispectral and LC-MS/MS results further indicated that ultrasound pretreatment altered the conformational and primary structural changes of the hydrolysates. The thermograms showed that ultrasound pretreatment mainly altered the epitope spectra of β-lactoglobulin hydrolysates, while it had less effect on the epitope spectra of α-lactalbumin hydrolysates. Additionally, ultrasound pretreatment significantly improved the foaming properties, antioxidant activity, and α-glucosidase inhibition of the hydrolysates without impairing the solubility and emulsification properties of the hydrolysates. Therefore, ultrasound pretreatment is a feasible method to reduce the allergenicity of WPH and to improve their functional properties and bioactivity. Notably, ultrasonic pretreatment improved the effectiveness and efficiency of WPI hydrolysis, which is a feasible method to produce high-quality protein feedstock in a green, efficient, and economical way.

The soaking process of glutinous rice allows the growth and reproduction of microorganisms, which can easily cause food safety problems. In this work, the effects of different ultrasonic powers (150 W, 300 W, 450 W, and 600 W) on the bactericidal effect of glutinous rice, the physicochemical properties of starch and the quality characteristics of sweet dumplings were studied. Compared with soaking for 0 and 2 h, sonication of glutinous rice after soaking for 4 h was more effective at reducing the number of microorganisms in soaked glutinous rice, and the bactericidal effect increased with increasing ultrasound intensity. After 30 min, the total number of bacteria decreased by 2.04 log CFU/g. Moreover, ultrasonic treatment destroys the grain structure of glutinous rice starch, resulting in the formation of dents and cracks on the starch surface, increasing the amylose content, improving its expansion, reducing its short-range order and relative crystallinity, and altering its gelatinization characteristics. In addition, ultrasonic treatment increased the soup transparency of sweet dumplings from 51.8 % to 63.95 %, reducing their hardness, chewiness and adhesiveness. In summary, ultrasonic treatment can not only effectively kill microorganisms in soaked glutinous rice but also improve the quality of glutinous rice dumplings by changing the physicochemical properties of glutinous rice starch. The results of this study provide theoretical support for the application of ultrasonic technology in glutinous rice food production.

Laser-induced cavitation bubbles offer precise control of the flow in space and time, but they are rarely used for the mechanical and chemical processing of liquids. Instead, strong acoustic fields are commonly used to nucleate and drive cavitation bubbles for liquid process applications. While acoustic field creates many more cavitation events, the resulting chaotic dynamics offers little control on the fluid mechanics, i.e., where and how bubbles deliver their energy. Here we present a method that utilizes a laser to nucleate a single cavitation bubble, which is then driven into violent oscillations by the ultrasound field, resulting in splitting of the bubble followed by formation of a cluster of cavitation bubbles. This combination offers means for cavitation control not available in conventional acoustic cavitation. Here, the cavitation bubble is generated with a custom build pulsed laser that is focused below a sonotrode driven at 20 kHz. In absence of the acoustic driving the bubble reaches a maximum diameter of 130 µm with a lifetime of approximately 10 µs. In the presence of the acoustic field the first few expansions and bubble collapses are strongly affected by the phase of nucleation. Over successive acoustic cycles a small bubble cluster develops that loses its connection with the phase of generation. We study the dynamics in the free field and constrained by a rigid boundary. For both geometries the cluster over many acoustic cycles dies off, yet through repetitive optical bubble seeding the cluster lifetime and its location can be controlled.

Environmental concerns linked to animal-based protein production have intensified interest in sustainable alternatives, with a focus on underutilized plant proteins. Faba beans, primarily used for animal feed, offer a high-quality protein source with promising bioactive compounds for food applications. This study explores the efficacy of ultrasound-assisted extraction under optimal conditions (123 W power, 1:15 g/mL solute/solvent ratio, 41 min sonication, 623 mL total volume) to isolate faba bean protein (U-FBPI). The ultrasound-assisted method achieved a protein extraction yield of 19.75 % and a protein content of 92.87 %, outperforming the control method’s yield of 16.41 % and protein content of 89.88 %. Electrophoretic analysis confirmed no significant changes in the primary structure of U-FBPI compared to the control. However, Fourier-transform infrared spectroscopy revealed modifications in the secondary structure due to ultrasound treatment. The U-FBPI demonstrated superior water and oil holding capacities compared to the control protein isolate, although its foaming capacity was reduced by ultrasound. Thermal analysis indicated minimal impact on the protein’s thermal properties under the applied ultrasound conditions. This research highlights the potential of ultrasound-assisted extraction for improving the functional properties of faba bean protein isolates, presenting a viable approach for advancing plant-based food production and contributing to sustainable protein consumption.

In recent years, ultrasound has emerged as a widely used technology for modifying proteins/peptides. In this study, we focused on the intrinsic mechanism of ultrasound-induced modification of bovine liver peptides, which were treated with ultrasound power of 0, 100, 200, 300, 400, and 500 W, and their physicochemical and functional properties, as well as ultrastructures, were investigated. The results show that ultrasound mainly affects hydrogen bonding and hydrophobic interactions to change the conformation of proteins and unfolds proteins through a cavitation effect, leading to an increase in biological activity. Fourier infrared spectroscopy showed that ultrasound inhibited the formation of hydrogen bonds and reduced intermolecular cross-linking. Molecular weight distribution showed that the antioxidant components of bovine liver polypeptides were mainly concentrated in fractions of 500–1,000 Da. Maximum values of ABTS (82.66 %), DPPH (76.02 %), chelated iron (62.18 %), and reducing power (1.2447) were obtained by treating bovine liver polypeptides with 500 W ultrasound. Combined with the scanning electron microscopy results, with the intervention of ultrasound, the impact force generated by ultrasonication may lead to the loosening of the protein structure, which further promotes the release of antioxidant peptides, and these findings provide new insights into the application of ultrasound in the release of antioxidant peptides from bovine liver.

This study evaluated the quality attributes of tomato sour soup marinade and investigated the effects of ultrasound-assisted marination on the physicochemical properties, microstructure, texture, sensory quality, and flavour profile of beef. The results showed that tomato sour soup significantly increased the marinade absorption rate and improved beef tenderloin’s physicochemical properties, texture, and flavour attributes compared to static brine (P < 0.05), with organic acids playing an essential role in the marinade tenderisation process. Compared to static sour soup marination, ultrasound treatment significantly accelerated the marination process, reducing beef’s shear force, hardness, and chewiness while increasing its tenderness. Microstructural observations revealed that sour soup marination induced a fragmented and irregular muscle fibre structure. Furthermore, sour soup marination significantly increased the relative concentrations of volatile flavour compounds, including alkanes, organic sulphides, alcohols, aldehydes, and aromatic compounds. Appropriate ultrasound treatment positively affects the texture and flavour characteristics of beef marinated with tomato sour soup, and the optimal approach was 320 W ultrasound treatment for 60 min. Overall, tomato sour soup improved beef’s textural and flavour attributes, while ultrasound-assisted marination is an effective processing method to improve the quality of meat products.

Endocrine disrupting compounds (EDCs) need to be removed by efficient treatment methods as they are a major concern for both human and environmental health. To reduce the impact of EDCs in water, this review examines the use of ultrasonic degradation processes. Following an overview of EDCs and their origins, the basic concepts of sonochemistry are examined, highlighting the potential of ultrasound in chemical reactions. An in-depth analysis of the variables that affect the ultrasonic degradation of EDCs, such as frequency, intensity/power, temperature and solution chemistry, prepares the reader for a case study investigation focusing on specific EDCs. The study also looks at synergistic methods, emphasizing how hybrid ultrasonic systems can improve removal efficiency. The study provides a comprehensive overview of the use of sonochemistry in the treatment of EDCs by addressing current issues and suggesting future research directions. The aim of this review paper is to provide insightful analysis and useful suggestions for scientists working on EDC remediation projects.

Nickel/iron-layered double hydroxide (NiFe-LDH) tends to undergo an electrochemically induced surface reconstruction during the water oxidation in alkaline, which will consume excess electric energy to overcome the reconstruction thermodynamic barrier. In the present work, a novel ultrasonic wave-assisted Fenton reaction strategy is employed to synthesize the surface reconstructed NiFe-LDH nanosheets cultivated directly on Ni foam (NiFe-LDH/NF-W). Morphological and structural characterizations reveal that the low-spin states of Ni²⁺ ($t_{2g}^6{e}_g^2$) and Fe²⁺ ($t_{2g}^4{e}_g^2$) on the NiFe-LDH surface partially transform into high-spin states of Ni³⁺ ($t_{2g}^6{e}_g^1$) and Fe³⁺ ($t_{2g}^3{e}_g^2$) and formation of the highly active species of NiFeOOH. A lower surface reconstruction thermodynamic barrier advantages the electrochemical process and enables the NiFe-LDH/NF-W electrode to exhibit superior electrocatalytic water oxidation activity, which delivers 10 mA cm⁻² merely needing an overpotential of 235 mV. Besides, surface reconstruction endows NiFe-LDH/NF-W with outstanding electrooxidation activities for organic molecules of methanol, ethanol, glycerol, ethylene glycol, glucose, and urea. Ultrasonic-assisted Fenton reaction inducing surface reconstruction strategy will further advance the utilization of NiFe-LDH catalyst in water and organics electrooxidation.