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1.
High-intensity ultrasound (HIU) is considered one of the promising non-chemical eco-friendly techniques used in food processing. Recently (HIU) is known to enhance food quality, extraction of bioactive compounds and formulation of emulsions. Various foods are treated with ultrasound, including fats, bioactive compounds, and proteins. Regarding proteins, HIU induces acoustic cavitation and bubble formation, causing the unfolding and exposure of hydrophobic regions, resulting in functional, bioactive, and structural enhancement. This review briefly portrays the impact of HIU on the bioavailability and bioactive properties of proteins; the effect of HIU on protein allergenicity and anti-nutritional factors has also been discussed. HIU can enhance bioavailability and bioactive attributes in plants and animal-based proteins, such as antioxidant activity, antimicrobial activity, and peptide release. Moreover, numerous studies revealed that HIU treatment could enhance functional properties, increase the release of short-chain peptides, and decrease allergenicity. HIU could replace the chemical and heat treatments used to enhance protein bioactivity and digestibility; however, its applications are still on research and small scale, and its usage in industries is yet to be implemented.  相似文献   

2.
Ultrasound (US) assisted thawing of blue honeysuckle berry was utilized in order to reduce the losses of bioactive components (ascorbic acid, anthocyanins, phenolic acids, iridoids, proanthocyanins) and increase the extraction efficiency during juice processing. It was analysed whether it was more beneficial to apply US (alone or with enzymatic treatment) to the frozen state, until reaching the cryoscopic temperature or thawed state. Both the US and enzymatic treatment significantly increased the extraction efficiency, extract content, acidity and the content of iridoids and chlorogenic acid in juices, especially if the US was applied to 50 °C. It was probably due to a higher extractivity by the greater damage of the tissue and detexturation. Enzymatic treatment due to long heating contributed to a higher degradation of anthocyanins, ascorbic acid and proanthocyanidins, which are more heat-sensitive. The results of the study mainly indicated the possibility of including ultrasound-assisted thawing in the fruit processing before pressing the juices. This may replace costly enzymatic treatment.  相似文献   

3.
Currently, as a promising alternative protein source, the interest of edible insect protein has been continuously increased. However, the extraction processing had distinct effects on the physicochemical properties and functionalities of this novel and sustainable protein. In this study, Tenebrio molitor larvae protein (TMLP) was extracted via ultrasound (US)-assisted alkaline extraction. The changes of extraction kinetics, physicochemical characteristics, and functional properties of TMLP as a function of US time (10, 20, 30, 40, 50 min) were investigated. The results showed that 30 min US treatment rendered the maximum protein yield (60.04 %) (P < 0.05). Meanwhile, Peleg's model was considered a suitable model to represent the extraction kinetics of TMLP, with a correlation coefficient of 0.9942. Moreover, the protein secondary structure, particle size, and amino acid profiles of TMLP were changed under the US-assisted alkaline extraction process. Additionally, a significant improvement of the functional properties of TMLP extracted with this method was observed compared to traditional alkaline extraction. In conclusion, the present work suggests that US-assisted alkaline extraction could be considered as a potential method to improve the protein yield, quality profiles, and functional properties of TMLP.  相似文献   

4.
Ultrasound is an advanced non-thermal food-processing technology that has received increasing amounts of interest as an alternative to, or an adjuvant method for, conventional processing techniques. This review explores the sono-physical and sono-chemical effects of ultrasound on food processing as it reviews two typical food-processing applications that are predominantly driven by sono-physical effects, namely ultrasound-assisted extraction (UAE) and ultrasound-assisted freezing (UAF), and the components modifications to food matrices that can be triggered by sono-chemical effects. Efficiency enhancements and quality improvements in products (and extracts) using ultrasound are discussed in terms of mechanism and principles for a range of food-matrix categories, while efforts to improve existing ultrasound-assist patterns was also seen. Furthermore, the progress of experimental ultrasonic equipments for UAE and UAF as food-processing technologies, the core of the development in food-processing techniques is considered. Moreover, sono-chemical reactions that are usually overlooked, such as degradation, oxidation and other particular chemical modifications that occur in common food components under specific conditions, and the influence on bioactivity, which was also affected by food processing to varying degrees, are also summarised. Further trends as well as some challenges for, and limitations of, ultrasound technology for food processing, with UAE and UAF used as examples herein, are also taken into consideration and possible future recommendations were made.  相似文献   

5.
Ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) techniques have been employed as complementary techniques to extract oils from vegetable sources, viz, soybean germ and a cultivated marine microalga rich in docosahexaenoic acid (DHA). Ultrasound (US) devices developed by ourselves, working at several frequencies (19, 25, 40 and 300 kHz), were used for US-based protocols, while a multimode microwave (MW) oven (operating with both open and closed vessels) was used for MAE. Combined treatments were also studied, such as simultaneous double sonication (at 19 and 25 kHz) and simultaneous US/MW irradiation, achieved by inserting a non-metallic horn in a MW oven. Extraction times and yields were compared with those resulting from conventional procedures. With soybean germ the best yield was obtained with a ‘cavitating tube’ prototype (19 kHz, 80 W), featuring a thin titanium cylinder instead of a conventional horn. Double sonication, carried out by inserting an immersion horn (25 kHz) in the same tube, improved the yield only slightly but halved the extraction time. Almost comparable yields were achieved by closed-vessel MAE and simultaneous US/MW irradiation. Compared with conventional methods, extraction times were reduced by up to 10-fold and yields increased by 50–500%. In the case of marine microalgae, UAE worked best, as the disruption by US of the tough algal cell wall considerably improved the extraction yield from 4.8% in soxhlet to 25.9%. Our results indicate that US and MW, either alone or combined, can greatly improve the extraction of bioactive substances, achieving higher efficiency and shorter reaction times at low or moderate costs, with minimal added toxicity.  相似文献   

6.
High hydrostatic pressure (HHP) has high success potential in pollen protein extraction, but its effect on pollen protein profiles has not been studied yet. The aim of this study is to put forward whether HHP processing causes a change in the protein profiles extracted from pollens or not. In this study, proteins extracted from Betula pendula pollens were studied at 100, 200 and 300?MPa at room temperature for 5?min. In addition, the efficiency of three different extraction solvents, namely phosphate buffer saline (PBS) buffer pH 7.5, trichloroacetic acid–acetone and Tris–HCl buffer pH 8.8, was also observed, and the results were compared with the conventional pollen protein extraction procedure. As a result, it is concluded that 200?MPa for 5?min has extracted similar amounts of protein compared with the conventional extraction method which lasted for 24?h, which lasted for 24 h. On the other hand, the application time for 200 MPa for 5 min is extremely shorter when it is compared to the conventional extraction method.  相似文献   

7.
Passion fruit bagasse is a rich source of phenolic compounds, including piceatannol, a stilbene to which several biological activities are conferred. This work reports the application of pressurized liquid extraction (PLE) assisted by ultrasound (US) to intensify the extraction of phenolic compounds from defatted passion fruit bagasse (DPFB). PLE at different temperatures (65–75 °C) without and with different US powers (240–640 W) was performed to investigate the mechanism of the assisted process. The extracts were evaluated in terms of global, total phenolic (TP), piceatannol and total reducing sugar yields. The antioxidant capacity of the extracts was determined by FRAP and ORAC assays. PLE assisted by US increased the yields, resulting in 60% more TP and piceatannol. The observed yields suggest that the main mechanism driving PLE assisted by US from DPFB was the rise in temperature caused by the ultrasonic waves. Pearson coefficient revealed a strong correlation between antioxidant capacity and total phenolics and piceatannol yield. The three-line spline model was adequately fitted to the experimental curves, showing three extraction periods in which the recovery of TP and piceatannol was higher than 70% at the end of the falling extraction rate period. PLE assisted or not by US showed to be clean, efficient and green alternatives for the recovery of phenolic compounds. The findings of this work indicate that PLE assisted by US has a great potential to improve the extraction of bioactive compounds from natural products.  相似文献   

8.
This review presents a complete picture of current knowledge on ultrasound-assisted extraction (UAE) in food ingredients and products, nutraceutics, cosmetic, pharmaceutical and bioenergy applications. It provides the necessary theoretical background and some details about extraction by ultrasound, the techniques and their combinations, the mechanisms (fragmentation, erosion, capillarity, detexturation, and sonoporation), applications from laboratory to industry, security, and environmental impacts. In addition, the ultrasound extraction procedures and the important parameters influencing its performance are also included, together with the advantages and the drawbacks of each UAE techniques. Ultrasound-assisted extraction is a research topic, which affects several fields of modern plant-based chemistry. All the reported applications have shown that ultrasound-assisted extraction is a green and economically viable alternative to conventional techniques for food and natural products. The main benefits are decrease of extraction and processing time, the amount of energy and solvents used, unit operations, and CO2 emissions.  相似文献   

9.
Ganoderma mushroom cultivated recently in Malaysia to produce chemically different nutritional fibers has attracted the attention of the local market. The extraction methods, molecular weight and degree of branching of (1-3; 1-6)-β-d-glucan polysaccharides is of prime importance to determine its antioxidant bioactivity. Therefore three extraction methods i.e. hot water extraction (HWE), soxhlet extraction (SE) and ultrasound assisted extraction (US) were employed to study the total content of (1-3; 1-6)-β-d-glucans, degree of branching, structural characteristics, monosaccharides composition, as well as the total yield of polysaccharides that could be obtained from the artificially cultivated Ganoderma. The physical characteristics by HPAEC-PAD, HPGPC and FTIR, as well as the antioxidant in vitro assays of DPPH scavenging activity and ferric reducing power (FRAP) indicated that (1-3; 1-6)-β-d-glucans of Malaysian mushroom have better antioxidant activity, higher molecular weight and optimal degree of branching when extracted by US in comparison with conventional methods.  相似文献   

10.
元素的形态分析在环境和生物分析中极其重要,因为元素在生物体内的作用及其代谢过程在很大程度上取决于元素存在的化学形态,而不仅仅是元素的总量。形态分析是指测定样品中构成元素总量的单独物理化学形式的浓度。最先进的形态分析方法是色谱分离和光谱检测的联用技术,特别是色谱和电感耦合等离子-质谱(ICP-MS)的联用。但是,联用技术的设备投入大、运行成本高,难以在常规实验室中的推广应用。在许多情况下,采用非色谱分离方法对样品进行处理,也可以得到足够的元素形态信息。基于非色谱分离、原子光谱测定的元素形态分析方法的费用低、操作简单、易于推广应用。本文总结了元素形态分析的样品前处理方法,综述了基于原子光谱法的元素形态分析中比较常用的非色谱分离技术,对溶剂萃取、浊点萃取、单滴微萃取、分散液液萃取等分离技术的原理、应用和优缺点进行了评述,介绍了固相萃取中常用的吸附剂及其在元素形态分离中的应用,以及氢化物发生、共沉淀等分离方法。相比于色谱分离方法,非色谱方法是快速、灵敏、廉价的分离技术。  相似文献   

11.
In spite of the high added value and tremendous output from duck processing industries, duck liver (DLv) is underutilized and a major factor is related to its prominent off-flavor perception which hampers the consumption and processing attributes. This work was designed to investigate the impact of low-frequency ultrasound (US) pretreatments on the headspace volatilome evolution of DLv and its isolated protein (DLvP) microstructure, aiming at exploring the potential of US technology to inhibit off-flavor perception and possible mechanisms behind. Results suggested that US pretreatment resulted in decreased lipid oxidation and off-flavor perception, simultaneously without significantly causing physicochemical influence including texture, pH and color. US induced obvious tertiary structural changes of DLvP, as revealed by the intrinsic fluorescence and surface hydrophobicity (H0), whereas the SH, S-S, secondary structure and molecular weight of DLvP remained unaffected, suggesting the presence of molten globule state (MG-state) under ultrasonic conditions. Besides, the headspace contents of flavor compounds, mainly aldehydes and alcohols, were significantly decreased whereas acids were increased. Multivariate analysis suggested an obvious US-induced effect on the volatilome evolution of DLv samples. Discriminant analysis recognized the aroma compounds including aldehydes and alkenals as the major contributors leading to the change of olfactory characteristics of DLv after ultrasonic treatment. Correlation analysis demonstrated the positive relationship between the volatile markers variation and the increased H0 values, a characteristic attribute of MG-state protein. The results obtained in this work suggested that US technology matched with suitable parameters could be a very promising approach to modulate the off-flavor perception of liver products by altering DLvP conformation.  相似文献   

12.
Ultrasound-assisted extraction is widely recognized as an eco-friendly technique due to low solvent consumption and time extraction as well as enhanced extraction efficiency with respect to conventional methods. Nevertheless, it would be convenient to avoid the usually used organic solvents to reduce the environment pollution. In this regard, Deep Eutectic Solvents (DES) represent nowadays a green and sustainable alternative for the extraction of bioactive compounds from natural sources. In this study, an efficient extraction of stevioside and rebaudioside A from Stevia rebaudiana coupling ultrasound with DES was developed. A solvent screening was performed using the predictive approach COnductor-like Screening MOdel for Real Solvent (COSMO-RS). The effect of three independent variables, namely % of water, temperature, and sonication amplitude, were investigated by the response surface methodology (RSM). Comparing ultrasound-assisted extraction (UAE) with conventional extraction, it has been demonstrated that the amount of steviol glycosides through UAE is almost three times higher than that obtained by the conventional method. Possible physicochemical factors involved in the UAE mechanism were discussed.  相似文献   

13.
The objective of this work was to develop a new process for pomegranate peels application in food industries based on ultrasound-assisted extraction of carotenoids using different vegetable oils as solvents. In this way, an oil enriched with antioxidants is produced. Sunflower oil and soy oil were used as alternative solvents and the effects of various parameters on extraction yield were studied. Extraction temperature, solid/oil ratio, amplitude level, and extraction time were the factors investigated with respect to extraction yield. Comparative studies between ultrasound-assisted and conventional solvent extraction were carried out in terms of processing procedure and total carotenoids content. The efficient extraction period for achieving maximum yield of pomegranate peel carotenoids was about 30 min. The optimum operating conditions were found to be: extraction temperature, 51.5 °C; peels/solvent ratio, 0.10; amplitude level, 58.8%; solvent, sunflower oil. A second-order kinetic model was successfully developed for describing the mechanism of ultrasound extraction under different processing parameters.  相似文献   

14.
A novel protein extraction method of ultrasound-assisted basic electrolyzed water (BEW) was proposed, and its effects on the structural and functional properties of Antarctic krill proteins were investigated. Results showed that BEW reduced 30.9% (w/w) NaOH consumption for the extraction of krill proteins, and its negative redox potential (−800 ~ −900 mV) protected the active groups (carbonyl, free sulfhydryl, etc.) of the proteins from oxidation compared to deionized water (DW). Moreover, the ultrasound-assisted BEW increased the extraction yield (9.4%), improved the solubility (8.5%), reduced the particle size (57 nm), favored the transition of α-helix and β-turn to β-sheet, promoted the surface hydrophobicity and disulfide bonds formation of krill proteins when compared to BEW without ultrasound. These changes contributed to the enhanced foam capacity, foam stability and emulsifying capacity of the krill proteins. Notably, all the physicochemical, structural and functional properties of the krill proteins were comparable to those extracted by the traditional ultrasound-assisted DW. This study suggests that the ultrasound-assisted BEW can be a potential candidate to extract proteins, especially offering an alternative way to produce marine proteins with high nutritional quality.  相似文献   

15.
Natural resource depletion, negative environmental effects and the challenge to secure global food security led to the establishment of the Sustainable Development Goals (SDGs). In need to explore underutilized sustainable protein sources, this study aims at isolating protein from cowpea by ultrasound-assisted extraction (UAE), where the techno-functional characteristics of the protein isolates were studied at different sonication conditions i.e., 100 W and 200 W at processing times ranging from 5 to 20 min. The US at 200 W-10 min produced the optimal results for all properties. In this process combination, there was an increase in protein yield, solubility, water-holding capacity, foaming capacity and stability, emulsion activity and stability, zeta-potential, and in-vitro protein digestibility from 31.78% to 58.96%, 57.26% to 68.85%, 3.06 g/g to 3.68 g/g 70.64% to 83.74%, 30.76% to 60.01%, 47.48% to 64.26%, 56.59% to 87.71%, –32.9 mV to −44.2 mV and 88.27% to 89.99%, respectively and particle size dropped from 763 nm to 559 nm in comparison to control. The microstructure and secondary-structure alterations of proteins caused by sonication were validated by SEM images, SDS-PAGE, and FTIR analyses. Sonication leads to acoustic cavitation and penetrate the cell walls, improving extraction from the solid to liquid phase. After sonication, the hydrophobic protein groups were exposed and proteins were partially denatured which increased its functionality. The findings demonstrated that UAE of cowpea protein improved yield, modify characteristics to fit the needs of the food industry, and contribute to achieving SDGs 2, 3, 7, 12, and 13.  相似文献   

16.
Green coconut water has unique nutritional and sensorial qualities. Despite the different technologies already studied, its enzymatic stability is still challenging. This study evaluated the use of ultrasound technology (US) for inactivating/sensitizing coconut water peroxidase (POD). The effect of both US application alone and as a pre-treatment to thermal processing was evaluated. The enzyme activity during US processing was reduced 27% after 30 min (286 W/L, 20 kHz), demonstrating its high resistance. The thermal inactivation was described by the Weibull model under non-isothermal conditions. The enzyme became sensitized to heat after US pre-treatment. Further, the use of US resulted in more uniform heat resistance. The results suggest that US is a good technology for sensitizing enzymes before thermal processing (even for an enzyme with high thermal resistance). Therefore, the use of this technology could decrease the undesirable effects of long times and/or the high temperatures of the conventional thermal processing.  相似文献   

17.
Custard apple seed oil is a marketable product extracted from custard apple seed which is a potential agriculture waste. The present work aims to elucidate simultaneous extraction of the custard apple seed oil and proteins using three phase partitioning (TPP). The efficient oil extraction was executed by optimization of parameters including time, slurry ratio, salt concentration, and slurry to t-butanol ratio. Additionally, the application of ultrasound as process intensification tool for TPP was studied that reduces the time of conventional TPP and increases the yield by 2.53%. The work also comprises a comparative study of two modes of ultrasound application, namely ultrasound pre-treatment and simultaneous ultrasound assisted TPP. This work proves ultrasonic pre-treatment followed by TPP as a superior mode of ultrasound application that attributes 33.6 ± 0.56% (w/w) oil extraction with optimized pre-treatment time of 150 s, 30 W ultrasound power and 75% duty cycle. Extraction kinetics studied for conventional, Ultrasound assisted Three Phase Partitioning (UTPP), and Ultrasound Pre-treatment assisted Three Phase Partitioning (UPTPP) were observed to fit Peleg’s model.  相似文献   

18.
等离子体排灰气处理系统是聚变反应装置氘氚燃料循环系统中极为重要的环节。该系统的主要功能是从反应后的排灰气中回收剩余的氘氚燃料,并处理壁材料净化、系统维护等非正常运行模式以及分析与辅助系统中产生的含氚杂质气体。介绍了国际上聚变堆等离子体排灰气的组成和主要处理工艺,简述了钯膜分离、膜反应及催化反应-膜分离、电解反应、分解反应及氧化-分解等各关键单元技术的基本原理和研究进展,并进行了分析和评价,提出了目前国内在该领域需要开展的研究工作。  相似文献   

19.
Maillard reaction (MR) is one of the most important chemical reactions in the food science domain with a long history of more than 100 years. As for ultrasound-assisted MR (US-MR), it has gradually drawn attention in a recent decade. Purpose of this paper is to provide a systematic review on recent advances of US-MR in model systems, glycation of protein, and food processing. Fundamental studies on simple MR model systems (i.e. reducing sugar and amino acid) have reported a promoted generation of colored and volatile MR products (MRPs). Critical steps influenced by US and possible mechanisms have been elucidated simultaneously. Other studies focused on modification of proteins which undergoes a glycation between proteins and saccharides as the initial stage of MR. Since the MR rate is extremely low in the presence of protein and saccharide, US becomes a promising mean of promoting the glycation. As a result, a number of functional properties of glycated protein obtained by US are significantly promoted, which extend their utilization in the food industry. The rest of studies reviewed in this article are concentrated on applying US to process real foods. Many attributes changed during US-assisted processing are induced by MR. Positive aspects brought by the promoted US-MR include enhanced antioxidant capacity and organoleptic properties (e.g. desirable color, low bitterness, enhanced flavor, etc.), as well as inhibited hazards (e.g. advanced glycation end-products, acrylamide, etc.) formed in the processed foods. Meanwhile, the promoted MR by US may also inevitably bring some negative aspects to the processed foods due to unfavored yellowish/browning colors, off-flavors and hazard components.  相似文献   

20.
《X射线光谱测定》2005,34(6):481-492
Proton beams can destroy tumors better than other radiation treatment options because they deliver their energy in a very accurate way, while leaving the surrounding tissue undamaged. However, it requires a very accurate prediction of the Bragg peak position within the patient's body. In existing proton treatment centers, the dose calculations are performed based on x‐ray computed tomography (CT) and the patient is positioned with x‐ray radiographs. During the 1970s and early 1980s, it was shown that the use of proton beams rather than conventional x‐rays could have some advantages. With the development of specialized medical proton gantries at Loma Linda University Medical Center (USA) and several other proton treatment centers worldwide, interest in this question has been renewed. The modern approach has advanced from simple proton film radiography to CT reconstructions from proton energy loss measurements employing individual proton tracking techniques. This permits image degradation due to multiple Coulomb scattering, one of the main problems of proton CT, to be reduced. Current work is devoted to the comparison of conventional x‐ray CT and proton computed tomography (pCT) as two alternative tools for measuring the physical properties of the human body, required for proton treatment planning. In this paper, a brief comparative overview of the physical basics of both methods are followed by the analysis of Monte Carlo simulation results. The first‐generation CT scheme was assumed for simplicity. The precisions relative to water volumetric electron density distributions, extracted from CT and pCT images, and the sources of absolute errors are discussed. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

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