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1.
The aim of this study was to examine the effect of ultrasound on the solvent extraction of anti-oxidants from the rosemary herb and to scale up the ultrasonic extraction process. The anti-oxidants of interest were identified using HPLC. Results indicated that, compared with conventional solvent extraction, the use of ultrasound gives a more effective extraction at lower temperatures with less dependence on the extraction solvent employed and that scale up of the process is possible.  相似文献   

2.
Apple pomace, a by-product of the cider production, has been studied as a potential source of polyphenols, compounds of great interest for the industry. Ultrasound has been used to improve extraction efficiency in terms of time needed and total polyphenol content. A preliminary study has been first investigated to optimize ethanol proportion of aqueous extractant (50%, v/v) and solid/liquid ratio (<15%, w/v). A response surface methodology has then been used to maximize total polyphenol content of extracts and investigate influence of parameters involved in extraction procedures for both total polyphenols content and composition of extracts. Optimal settings reached from a central composite design were applied for ultrasound-assisted extraction and were compared to conventional procedure: yields were increased by more than 20%. Ultrasound-assisted polyphenols extraction from apple pomace appears to be a relevant, rapid, sustainable alternative to conventional procedure, and that scale up of the process is possible.  相似文献   

3.
The paper presents our results concerning the ultrasonically assisted extraction of bioactive principles from plant material. A comparison with classical methodologies is presented and technological aspects of ultrasonically assisted extraction are discussed.  相似文献   

4.
The instant controlled pressure drop (DIC) technology enabled both the extraction of essential oil and the expansion of the matrix itself which improved solvent extraction. The sequential use of DIC and Ultrasound Assisted Extraction (UAE) triggered complementary actions materialized by supplementary effects. We visualized these combination impacts by comparing them to standard techniques: Hydrodistillation (HD) and Solvent Extraction (SE). First, the extraction of orange peel Essential Oils (EO) was achieved by HD during 4 h and DIC process (after optimization) during 2 min; EO yields was 1.97 mg/g dry material (dm) with HD compared to 16.57 mg/g dm with DIC. Second, the solid residue was recovered to extract antioxidant compounds (naringin and hesperidin) by SE and UAE. Scanning electron microscope showed that after HD the recovered solid shriveled as opposite to DIC treatment which expanded the product structure. HPLC analyses showed that the best kinetics and yields of naringin and hesperidin extraction was when DIC and UAE are combined. Indeed, after 1 h of extraction, DIC treated orange peels with UAE were 0.825 ± 1.6 × 10?2 g/g of dry material (dm) for hesperidin and 6.45 × 10?2 ± 2.3 × 10?4 g/g dm for naringin compared to 0.64 ± 2.7 × 10?2 g/g of dry material (dm) and 5.7 × 10?2 ± 1.6 × 10?3 g/g dm, respectively with SE. By combining DIC to UAE, it was possible to enhance kinetics and yields of antioxidant extraction.  相似文献   

5.
Ultrasound is well known to have a significant effect on the rate of various processes in the food industry. Using ultrasound, full reproducible food processes can now be completed in seconds or minutes with high reproducibility, reducing the processing cost, simplifying manipulation and work-up, giving higher purity of the final product, eliminating post-treatment of waste water and consuming only a fraction of the time and energy normally needed for conventional processes. Several processes such as freezing, cutting, drying, tempering, bleaching, sterilization, and extraction have been applied efficiently in the food industry. The advantages of using ultrasound for food processing, includes: more effective mixing and micro-mixing, faster energy and mass transfer, reduced thermal and concentration gradients, reduced temperature, selective extraction, reduced equipment size, faster response to process extraction control, faster start-up, increased production, and elimination of process steps. Food processes performed under the action of ultrasound are believed to be affected in part by cavitation phenomena and mass transfer enhancement. This review presents a complete picture of current knowledge on application of ultrasound in food technology including processing, preservation and extraction. It provides the necessary theoretical background and some details about ultrasound the technology, the technique, and safety precautions. We will also discuss some of the factors which make the combination of food processing and ultrasound one of the most promising research areas in the field of modern food engineering.  相似文献   

6.
After preparation of medicine tinctures from the herbal plant Salvia officinalis by classical and ultrasound-assisted extraction with aqueous ethanol, the insoluble plant residues were subsequently treated with hot water and dilute alkali to isolate polysaccharide cell wall components. The yields of the hot water extract as well as total extracted polysaccharides were higher in the case of the ultrasound-treated plant in both laboratory and pilot plant experiments. The water-extractable polysaccharide fractions, in all cases, contained glucose, galactose and arabinose as main sugar components, whereas the alkali-extractable fractions were rich in xylans. The fractions also contained considerable amounts of proteins. The water-soluble polysaccharides may contribute to the biological activity of the plant decoction. The results indicate that the addition of a subsequent extraction step during the preparation of the herbal tincture might contribute to a better exploitation of the raw material.  相似文献   

7.
Ultrasound has a significant effect on the rate of various processes in food, perfume, cosmetic, pharmaceutical, bio-fuel, materials, or fine chemical industries, despite some shortcomings. Combination with other conventional or innovative techniques can overcome these limitations, enhance energy, momentum and mass transfer, and has been successfully demonstrated in many recent studies. Various ultrasound combined hybrid and innovative techniques are systematically summarized in this review for the first time. Ultrasound can be combined with diverse conventional techniques including Soxhlet, Clevenger, enzyme, hydrotropes, ionic liquids, Deep Eutectic Solvents (DES) or Natural Deep Eutectic Solvents (NADES), to enhance mixing and micro-mixing, reduced thermal and concentration gradients, and selective extraction. Moreover, combinations of ultrasound with other innovative techniques such as microwave, extrusion, supercritical fluid, subcritical and pressure liquids, Instant controlled pressure drop (DIC), Pulsed Electric Field (PEF), Ultra-Violet (UV) or Infra-Red (IR) radiations, Counter-current chromatography (CCC), or centrifugal partition chromatographs (CPC) can enable reduced equipment size, faster response to process control, faster start-up, increased production, and elimination of process steps. The theories and applications of these ultrasound combined hybrid and innovative techniques as well as their advantages and limitations are compared, and further perspectives are proposed. This review provides new insights into advances in ultrasound combined techniques and their application at research, educational, and industrial level in modern food and plant-based chemistry.  相似文献   

8.
Abstract

Hydrostatic pressure technology is a novel non-thermal food processing technology whereby foods are subjected to high hydrostatic pressure, generally in the range of 100 to 600 MPa, at or around room temperature.  相似文献   

9.
The insoluble plant residues, obtained after preparation of medicinal tinctures from the roots of valerian (Valeriana officinalis L.) by classical and ultrasound-assisted extraction with aqueous ethanol in a pilot plant, were subsequently treated with hot water to isolate the accessible polysaccharide cell wall components. At almost equal amounts of the hot-water extractable material, the yields of the recovered polysaccharides were lower in the ultrasonical experiment. This is due to the fact that a part of accessible polysaccharides were already solubilised by the aqueous ethanol and recoverable from the medicinal tincture. Therefore, the net yield of extracted polysaccharides was enhanced in the ultrasonical procedure. This fact as well as the sugar composition and structural features of the isolated polysaccharides suggest that ultrasonication have attacked the integrity of cell walls, released and degraded its most accessible polysaccharides (pectic polysaccharides and starch) and increased also the extractibility of its less accessible components--xylan, mannan and glucan. The water-soluble polysaccharide fractions from both the conventional and ultrasonical experiments exhibit significant immunostimulatory activities in mitogenic and comitogenic thymocyte tests.  相似文献   

10.
A quantitative analysis of the total content low-molecular antioxidants in extracts from food and medicinal plants with the help of a method based on the interaction of antioxidants with 2,2-diphenyl-1-picrylhydrazyl (DPPH), a stable radical, and of the amperometric method is performed. The results obtained by these two methods exhibit a high correlation (r = 0.96). A comparative analysis of the total content of antioxidants (AOs) in 14 food and medicinal plants and of the activity of these AOs with respect to DPPH was conducted.  相似文献   

11.
The objective of this work is to discuss the main parameters that influence the sonication extraction of Ilex paraguariensis leaves. For this purpose, the extraction time, solvent polarity, solvent volume, sample mass and particle size were evaluated. Results showed that the main variable affecting the extraction process was the solvent polarity. Though in a less extent, temperature and extraction time also demonstrated to be important parameters, while the other variables did not present a significant influence on the extraction yield. The extracts at the optimized condition were compared with those obtained by maceration, in terms of mass yield and chemical composition. The major compounds identified in the extracts were caffeine and palmitic acid. Some saturated hydrocarbons such as fatty acids, fatty acid methyl esters, phytosterols, and theobromine were also identified in the fractions.  相似文献   

12.
13.
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   

14.
Concept of waste to wealth is a hot topic with research ongoing globally to reduce carbon footprint. In an effort to follow up this cause present study focused on tomato industry waste specifically the peel of tomatoes for extraction of pectin. Pectin extraction was performed using five different extraction techniques (Ultrasound assisted extraction (UAE); microwave assisted extraction (MAE); ohmic heating assisted extraction (OHAE); ultrasound assisted microwave extraction (UAME) and ultrasound assisted ohmic heating extraction (UAOHE) at different power levels to study its extraction and degradation kinetics and in turn to optimize the extraction process. The extracted pectin yield ranged from 9.30% for OHAE to 25.42% for MAE. Also, there was very less difference in the yield of MAE and UAME extracted pectin, but at the cost of major difference in degree of esterification 59.76 ± 0.70 and 73.33 ± 1.76%, respectively. In addition, all the pectin extracted under optimized conditions was having acceptable purity, [Galacturonic acid (GalA) content ranged from 675.8 ± 11.31 to 913.3 ± 20.50 g/kg of pectin]. FTIR analysis confirmed the presence of functional groups in the finger print region of identification for polysaccharide in all the extracted pectin. According to obtained results, UAME can be considered as better green extraction technology in terms of extraction yield as well as in quality of pectin compared to the other treatments used. Therefore, results suggest that UAME can be used as an efficient pectin extraction method from tomato processing waste.  相似文献   

15.
超声波在食品技术中的应用   总被引:14,自引:0,他引:14       下载免费PDF全文
强超声在媒质中传播时产生力学效应、空化效应和热效应,产匝此增强质量传输和热传递,对介质产生强的切向力。本文对超声波在辅助或强化提取,冷冻、乳化、结晶和干燥等食品的加工技术中应用加以综述。  相似文献   

16.
Abstract

High pressure (HP) technology appears to be of paramount interest for valuable applications in pharmacy and medicine, owing to academic studies and industrial developments of this technology for food processing. The main potential application of HP between 100 MPa and 1200 MPa (1 kbar to 12kbar) is the inactivation of biological agents (bacteria, moulds, yeasts, virus and even prions) which allows the sterilization (i.e, “pascalization”) of thermo-, chemo-, or radio-sensitive materials and chemicals. The immunogenicity of some pressure-killed bacteria or virus suggests also the potentiality of making new vaccines. Another interest of the HP technology is the possibility of storage at subzero temperatures without freezing of cells and animal tissues to be used for cells and organs for transplant. HP engineering may be used for enzyme-catalyzed synthesis of fine chemicals, production of modified proteins of medical or pharmaceutical interest, and organic synthesis of pharmaceuticals.  相似文献   

17.
In this paper an ultrasound assisted procedure for the extraction of the bio-available fraction of humic substance in marine sediments is described. The proposed method is based on a preliminary 24 h 8 M HCl treatment already proposed in a previous paper [M. Mecozzi, E. Pietrantonio, M. Amici, Fres. Environ. Bull. 7 (1998) 605], followed by consecutive extractions by 0.5 M NaOH coupling to an ultrasonic treatment. The main advantages of the ultrasound procedure are the reduced times of extraction which take 30 min in contrast to the 24 h required by shaking method and the possibility to perform also the quantitative estimation of the extractable fraction of humic substance present in marine samples.  相似文献   

18.
Power ultrasound, as an emerging green technology has received increasing attention of the petroleum industry. The physical and chemical effects of the periodic oscillation and implosion of acoustic cavitation bubbles can be employed to perform a variety of functions. Herein, the mechanisms and effects of acoustic cavitation are presented. In addition, the applications of power ultrasound in the petroleum industry are discussed in detail, including enhanced oil recovery, oil sand extraction, demulsification, viscosity reduction, oily wastewater treatment and oily sludge treatment. From the perspective of industrial background, key issue and resolution mechanism, current applications and future development of power ultrasound are discussed. In addition, the effects of acoustic parameters on treatment efficiency, such as frequency, acoustic intensity and treatment time are analyzed. Finally, the challenges and outlook for industrial application of power ultrasound are discussed.  相似文献   

19.
Ultrasonic technology was applied for extraction of polyphenols and antioxidants from the rice bran using ethanol as a food grade solvent. Response surface methodology (RSM) was used to optimize experimental conditions for extraction of polyphenols and antioxidants. Three independent variables such as solvent percentage (%), temperature (°C) and time (min) were studied. Effect of ethanol concentration was found to be significant on all responses. Total phenolic content (TPC) varied from 2.37 to 6.35mg gallic acid equivalent/g of dry sample. Antioxidant activity of the extracts was determined by the ferric reducing antioxidant power (FRAP) assay and scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. FRAP and DPPH values varied from 31.74 to 57.23μmol Fe(2+)/g of dry sample and 16.88% to 55.61% inhibition, respectively. Extraction yields ranged from 11 to 20.2%. Optimal ultrasonic-assisted extraction (UAE) conditions were identified as 65-67% ethanol, 51-54°C, 40-45min. The experimental values agreed with those predicted by SRM models, thus indicating suitability of the model employed and the success of RSM in optimizing the extraction conditions.  相似文献   

20.
The effect of high-power ultrasound pretreatment on the extraction of podophyllotoxin from Podophyllum peltatum was investigated. Direct sonication by an ultrasound probe horn was applied at 24 kHz and a number of factors were investigated: particle size (0.18-0.6 mm), type of solvent (0-100% aqueous ethanol), ultrasonic treatment time (2-40 min), and power of ultrasound (0-100% power intensity, maximum power: 78 W). The optimal condition of ultrasound was achieved with 0.425-0.6 mm particle size, 10 min sonication time, 35 W ultrasound power, and water as the medium. There was no obvious degradation of podophyllotoxin with ultrasound under the applied conditions, and an improvement in extractability was observed. The SEM microscopic structure change of treated samples disclosed the effect of ultrasound on the tissue cells. The increased pore volume and surface area after ultrasonic treatment also confirmed the positive effect of ultrasound pretreatment on the extraction yield of podophyllotoxin from the plant cells.  相似文献   

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