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1.
The degradation of phorate in apple juice by sonication was investigated in the present study. Results showed that sonication was effective in eliminating phorate in apple juice, and the ultrasonic power and sonication time significantly influenced the degradation of phorate (< 0.05). The degradation of phorate followed the first-order kinetics model well. Phorate-oxon and phorate sulfoxide were identified as the degradation products of phorate by gas chromatography-mass spectrometry (GC-MS). Moreover, the toxicity of apple juice samples spiked with phorate was significantly reduced by sonication (< 0.05). The quality indexes of apple juice including pH, titratable acidity (TA), electrical conductivity (EC), total soluble solids (TSS), and the contents of sucrose, glucose and fructose were not affected by sonication, and no visible difference in color was observed between the sonicated samples and the control.  相似文献   

2.
A study was initiated with the objective of evaluating the effects of sonication treatment on important quality parameters of extract of Pinus massoniana pollen. Sonication of extract was done (frequency 20 kHz and various amplitude levels) for 10, 30, 50 min, respectively. As results, total polysaccharide, phenolics and flavonoids significantly increased (P < 0.05). And sonicated P. massoniana pollen displays strong immuno-stimulating activity by increasing proliferations of splenic lymphocytes and subsets of CD4+ T cells (CD3+CD4+), CD8 T cells (CD3+CD8+), and increased Ig secretion. Sonicated P. massoniana pollen also showed anti-tumor function by inhibition of tumor cell proliferation, inhibition of ROS production, up-regulation of GSH/GSSG ration, up-regulating the gene expression of P53, Bax and down-regulating the gene expression of Bcl-2. Findings of the present study suggested the sonication treatment of P. massoniana pollen could improve the quality and bioactivity of P. massoniana pollen, indicating that sonication is effective in processing of pollen and could be a potential process in tumor prevention and treatment.  相似文献   

3.
Fresh apple juice treated with ultrasound (for 0, 30, 60 and 90 min, at 20 °C, 25 kHz frequency) was evaluated for different physico-chemical, Hunter color values, cloud value, antioxidant capacity, scavenging activity on 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical, ascorbic acid, total phenolics, flavonoids, flavonols and microbial characteristics. No significant effect of sonication was observed on pH, total soluble solids (°Brix) and titratable acidity of apple juice. Sonication significantly improved ascorbic acid, cloud value, phenolic compounds, antioxidant capacity, DPPH free radical scavenging activity and differences in Hunter color values. Moreover, significant reduction in microbial population was observed. Findings of the present study suggested that sonication treatment could improve the quality of apple juice. It may successfully be employed for the processing of apple juice with improved quality and safety from consumer’s health point of view.  相似文献   

4.
Ultrasonic treatment is an emerging food processing technology that has growing interest among health-conscious consumers. Freshly squeezed Chokanan mango juice was thermally treated (at 90 °C for 30 and 60 s) and sonicated (for 15, 30 and 60 min at 25 °C, 40 kHz frequency, 130 W) to compare the effect on microbial inactivation, physicochemical properties, antioxidant activities and other quality parameters. After sonication and thermal treatment, no significant changes occurred in pH, total soluble solids and titratable acidity. Sonication for 15 and 30 min showed significant improvement in selected quality parameters except color and ascorbic acid content, when compared to freshly squeezed juice (control). A significant increase in extractability of carotenoids (4–9%) and polyphenols (30–35%) was observed for juice subjected to ultrasonic treatment for 15 and 30 min, when compared to the control. In addition, enhancement of radical scavenging activity and reducing power was observed in all sonicated juice samples regardless of treatment time. Thermal and ultrasonic treatment exhibited significant reduction in microbial count of the juice. The results obtained support the use of sonication to improve the quality of Chokanan mango juice along with safety standard as an alternative to thermal treatment.  相似文献   

5.
Sonication is an emerging sustainable and eco-friendly technology that has been broadly explored in food processing and preservation. Sonication has the edges of low energy consumption and high efficiency than conventional decontamination methods and would not pass on secondary pollutants. In the current research, we analyzed the impact of sonication on anilazine fungicide reduction, bioactive compound, antioxidant activity, colloidal stability, and enzymatic and microbial load of tomato juice. Sonicated treatments were carried out at 40 kHz, 480 W, 30 ± 2 °C for 0, 8, 16, 24, 32, and 40 min in an ultrasonic bath cleaner. The GC–MS outcomes revealed that the anilazine maximum reduction in tomato juice attained 80.52 % at 40 min of sonication. The anilazine concentration reduced significantly (p ≤ 0.05) with increased sonication time. In contrast, sonication treatments have acquired the highest TFC, TPC, ascorbic acid, carotenoids, lycopene, ABTS, and ORAC assay than the untreated sample. The Sonication process significantly improved (p ≤ 0.05) colloidal stability by reducing particle size distribution, apparent viscosity, and sedimentation index. Sonication prolonged tomato juice's shelf life by reducing the total viable count from 6.31 to 1.91 log CFU/mL. Polygalacturonase and pectin methyl esterase of the sonication sample at 40 min were inactivated by 44.32 % and 64.2 %, respectively. Considering this issue from a future perspective, sonication processing can be used industrially to enhance fruit juice's nutritional properties and shelf life and reduce pesticides and other organic residues.  相似文献   

6.
Sonication and dielectric barrier discharge (DBD) plasma are sustainable emerging food processing technologies. The study investigates the impact of sonication, DBD-plasma, and thermal treatment (TT) on wheat sprout juice. The obtained results indicated a significant (p < 0.05) increase in chlorophyll, total phenolics, flavonoids, DPPH assay, and ORAC assay after DBD-plasma (40 V) and sonication (30 mins) treatment as compared to TT and untreated samples. Both emerging technologies significantly (p < 0.05) reduce the polyphenol oxidase and peroxidase activities, but the TT sample had the highest reduction. Moreover, the synergistic application of both technologies significantly reduced the E. coli/Coliform, aerobics, yeast and mold up to the 2 log reduction, but the TT sample had a complete reduction. DBD-plasma and sonication processing significantly decreased (p < 0.05) the particle size, reducing apparent viscosity (η) and consistency index (K); while increasing the flow behavior (n), leading to higher stability of wheat sprout juice. To assess the impact of emerging techniques on nutrient concentration, we used surface-enhance Raman spectroscopy (SERS) as an emerging method. Silver-coated gold nano-substrates were used to compare the nutritional concentration of wheat sprout juice treated with sonication, DBD-plasma, and TT-treated samples. Results showed sharp peaks for samples treated with DBD-plasma followed by sonication, untreated, and TT. The obtained results, improved quality of wheat sprout juice, and lower microbial and enzymatic loads were confirmed, showing the suitability of these sustainable processing techniques for food processing and further research.  相似文献   

7.
In order to obtain noni juice with high yield and good quality, the effect of combined extraction technique of enzymatic treatment (EZ) and ultrasonication (US) on the overall quality of noni juice was investigated. Moreover, the extraction performance of the EZ-US combined extraction technique was compared with that of EZ-based extraction and the US-based extraction. Response surface methodology (RSM) was designed to optimize the parameters of ultrasonic treatment, by taking consideration of the extraction efficiency, quality parameters and bioactive ingredients of noni juice. The results indicated that combined ultrasonic and enzymatic treatment achieved a synergistic effect on promoting the quality of noni juice. The maximum juice yield of 67.95 % was obtained under ultrasonication for 10 min at 600 W after enzymatic treatment (EZU). In addition, EZU-treated juice exhibited the highest contents of total phenolic and flavonoid, which were 148.19 ± 2.53 mg gallic acid/100 mL and 47.19 ± 1.22 mg rutin/100 mL, respectively, thus contributing to better antioxidant activity. Moreover, the EZU treatment significantly reduced the particle size of noni juice, and improved its suspension stability and rheological properties. FTIR results indicated that the treatments did not bring major changes in the chemical structure and the functional groups of compounds in noni juice. Therefore, EZU treatment can be successfully applied to the extraction of noni juice with better nutritional properties and overall quality.  相似文献   

8.
The objective of this study was to evaluate the effect of different treatments—heat treatment (HT), sonication (SC), thermosonication (TS), manosonication (MS), manothermal (MT), and manothermosonication (MTS) on Escherichia coli O157:H7, polyphenol oxidase (PPO), and anthocyanin content in blueberry juice. First, samples were treated at different temperatures (30, 40, 50, 60, 70, and 80 °C) and power intensities (280, 420, 560, and 700 W) for 10 min. Subsequently, samples were treated using combinations of power intensity and mild temperature for 10 min. For further study, samples were treated using HT (80 °C), TS (40 °C, 560 W), MT (350 MPa, 40 °C), MS (560 W, 5 min/350 MPa), or MTS (560 W, 5 min, 40 °C/350 MPa, 40 °C) for 5, 10, 15, 20 min for each treatment, and the results compared between treatments. HT significantly reduced PPO activation (2.05% residual activity after only 5 min), and resulted in a 2.00-log reduction in E. coli O157:H7 and an 85.25% retention of anthocyanin. Escherichia coli O157:H7 was slightly inactivated by TS after 5 min (0.17-log reduction), while residual PPO activity was 23.36% and anthocyanin retention was 98.48%. However, Escherichia coli O157:H7 was rapidly inactivated by MTS (5.85-log reduction) after 5 min, while anthocyanin retention was 97.49% and residual PPO activity dropped to 10.91%. The destruction of E. coli cells as a result of these treatments were confirmed using SEM and TEM. Therefore, a combination of sonication, high pressure, and mild heat allows the safety of blueberry juice to be maintained without compromising the retention of desirable antioxidant compounds.  相似文献   

9.
This work explored the effect of ultraviolet-assisted ultrasound (US-UV) as an emerging non-thermal sterilization technology on mango juice in aspects of microbial growth and quality changes. The juice in the ice bath was subjected to US-UV treatment at different US powers (0–600 W) and times (0–40 min), and no pathogen bacteria could be detected after treatment, while the physicochemical features (particle size, suspension stability, color, content of total polyphenols, carotenoids, sugar, reducing sugar and protein) and antioxidant ability of treated juice was preserved or improved to some extent. Based on these results, we further validated its positive effects on the nutritional value (content of ascorbic acid and soluble dietary fiber, antioxidant ability) and quality parameters (titratable acid, sugar acidity, total soluble solids, rheological behavior, metal elements) of mango juice treated at the optimal US parameter (10 min, 600 W); Not only the inactivation of polyphenol oxidation enzyme, peroxidase and pectin methylesterase was achieved but also the treated juice has a significant different volatile profile compared with the fresh juice, which might offer the better color, texture, and smell. Importantly, through the HPLC-MSD-Trap-XCT (phenols) and UPLC-Q Exactive Orbitrap-MS (carotenoids) study, the US-UV treatment will not cause difference on compounds composition, but it was responsible for changes in content of individual compounds, especially the all-trans-β-carotene, became the main component of carotenoids in processed mango juice (increased from 43.72% to 75.15%, relative content), and the oxygenated carotenoids (xanthophylls) are highly sensitive to the US (reduced from 50.96% to 4.85%) while the carotenes show a strong resistance to the US (increased 49.04% to 95.15%). Thus, the overall safety and quality of mango juice were enhanced while the sensory characteristics remained stable, suggesting that this non-thermal combination sterilization processing may successfully be implemented in the commercial processing of mango juice.  相似文献   

10.
The inactivation of Saccharomyces cerevisiae NCFB 3191 using high hydrostatic pressure of 300 MPa at 20°C with a holding time of 0, 1, 5 and 10 min was investigated with model suspensions in phosphate-buffered saline and in beetroot juice. The reduction in S. cerevisiae NCFB 3191 in model suspensions was about 5 log after 10 min of pressurization, irrespective of the initial level of cell concentration in the samples (5.4–8.7 log cfu/mL). The baroprotective effect of beetroot juice on yeast cells during pressurization was observed; the reduction was lower and was only 3.5 log (the inoculum was 5.4 log cfu/mL). No sublethal injury among the surviving cells of the studied yeast strain was found.  相似文献   

11.
The aim of this study was to investigate the effect of high hydrostatic pressure (HHP) treatment (200, 300, 400?MPa; 5°C, 15°C and 25°C; 5 and 10 min) on some quality properties of pomegranate juice. Juice samples are obtained under industrial conditions at two different squeezing pressure levels (100 and 150?psi – 0.689 and 1.033?MPa, respectively). Results are compared against conventional thermal treatment (85°C/10 min) and raw sample. For all three processing temperature, HHP combinations at 400?MPa for 10 min were sufficient to decrease the microbial load around 4.0 log cycles for both squeeze levels. All HHP treatments showed no significant decrease at antioxidant activity, total phenolic content and monomeric anthocyanin pigment concentrations, while there was a significant decrease (p?≤?.05) in thermal-treated samples. Being the highest sugar alcohol in pomegranate juice, mannitol content must be considered for determining the authenticity, and mannitol content increased with squeezing pressure and thermal treatment.  相似文献   

12.
Three-dimensional analysis of intensity distribution in the interference field of two interfering waves enables one to reconstruct the corresponding wave vectors at each point in space. This has been exploited to specify the radii of curvature, the refractive indices and the thicknesses of a single lens and components of a doublet. The introduced technique is very suitable for lenses of small diameters and short focal lengths.  相似文献   

13.
The exceptional properties of graphene and its structural uniqueness can improve the performance of nanocomposites if it can attain the uniform dispersion. Tip sonication assisted graphene solvent dispersion has been emerged as an efficient approach but it can cause significant degradation of graphene structure. This study aimed to evaluate the parametric influence of tip sonication on the characteristics of sp2 carbon structure in graphene nanoplatelets by varying the sonication time and respective energy at three different amplitudes (60%, 80% and 100%). The study is essential to identify appropriate parameters so as to achieve high-quality and defect-free graphene with a highly desirable aspect ratio after solvent dispersion for composite reinforcement. Quantitative approach via Raman spectroscopy is used to find the defect ratio and lateral size of graphene evolved under the effect of tip sonication parameters. Results imply that the defect ratio is steady and increases continually with GNPs, along with the transformation to the nano-crystalline stage I up to 60 min sonication at all amplitudes. Exfoliation was clearly observed at all amplitudes together with sheet re-stacking due to considerable size reduction of sheets with large quantity. Finally, considerable GNPs fragmentation occurred during sonication with increased amplitude and time as confirmed by the reduction of sp2 domain (La) and flake size. This also validates the formation of edge-type defect in graphene. Convincingly, lower amplitude and time (up to 60 min) produce better results for a low defect content and larger particle size as quantified by Raman analysis.  相似文献   

14.
Sugarcane juice (Saccharum officinarum) is a proven nutritious beverage with high levels of antioxidants, polyphenols, and other beneficial nutrients. It has recently gained consumer interest due to its high nutritional profile and alkaline nature. Still, high polyphenolic and sugar content start the fermentation in juice, resulting in dark coloration. Lately, some novel techniques have been introduced to extend shelf life and improve the nutritional value of sugarcane juice. The introduction of such processing technologies is beneficial over conventional processes and essential for producing chemical-free, high-quality, fresh juices. The synergistic impact of these novel technologies is also advantageous for preserving sugarcane juice. In literature, novel thermal, non-thermal and hurdle technologies have been executed to preserve sugarcane juice. These technologies include high hydrostatic pressure (HHP), ultrasound (US), pulsed electric field (PEF), ultraviolet irradiation (UV), ohmic heating (OH), microwave (MW), microfludization and ozone treatment. This review manifests the impact of novel thermal, non-thermal, and synergistic technologies on sugarcane juice processing and preservation characteristics. Non-thermal techniques have been successfully proved effective and showed better results than novel thermal treatments. Because they reduced microbial load and retained nutritional content, while thermal treatments degraded nutrients and flavor of sugarcane juice. Among non-thermal treatments, HHP is the most efficient technique for the preservation of sugarcane juice while OH is preferable in thermal techniques due to less nutritional loss.  相似文献   

15.
The objective of this study was to evaluate changes in color, betalain content, browning index, viscosity, physical stability, microbiological growth, antioxidant content and antioxidant activity of purple cactus pear juice during storage after thermoultrasonication at 80% amplitude level for 15 and 25 min in comparison with pasteurized juice. Thermoultrasound treatment for 25 min increased color stability and viscosity compared to treatment for 15 min (6.83 and 6.72 MPa, respectively), but this last parameter was significantly lower (p < 0.05) compared to the control and pasteurized juices (22.47 and 26.32 MPa, respectively). Experimental treatment reduced significantly (p < 0.05) sediment solids in juices. Total plate counts decreased from the first day of storage exhibiting values of 1.38 and 1.43 log CFU/mL, for 15 and 25 min treatment, respectively. Compared to the control, both treatments reduced enterobacteria counts (1.54 log CFU/mL), and compared to pasteurized juice decreased pectinmethylesterase activity (3.76 and 3.82 UPE/mL), maintained high values of ascorbic acid (252.05 and 257.18 mg AA/L) and antioxidant activity (by ABTS: 124.8 and 115.6 mg VCEAC/100 mL; and DPPH: 3114.2 and 2757.1 μmol TE/L). During storage thermoultrasonicated juices had a minimum increase in pectinmethylesterase activity (from day 14), and exhibited similar total plate counts to pasteurized juice. An increase of phenolic content was observed after 14 days of storage, particularly for treatment at 80%, 25 min, and an increase in antioxidant activity (ABTS, DPPH) by the end of storage.  相似文献   

16.
采用考虑Davidson修正的内收缩多参考组态相互作用方法和相关一致基aug—CC—pV5Z,在0.103—1.083nm的核间距内计算了SO+离子b4∑-态的势能曲线.采用态相互作用方法和非收缩全电子aug.CC—pCVTZ基组、利用完全Breit—Pauli算符计算了旋轨耦合效应对光谱常数的影响.为提高势能曲线和旋轨耦合常数的计算精度,考虑了核价相关效应和相对论效应对势能曲线的影响.核价相关效应是使用CC—pCVTZ基组计算的;相对论效应是在-cc-pV5Z基组水平上使用三级Douglas.Kroll.Hess哈密顿算符计算的.利用得到的势能曲线,计算了各种情况下的光谱常数,并进行了详尽的分析和讨论.结果表明:在MRCI+Q/aug—cc—pV5Z+CV+DK理论水平获得的光谱常数总体上最接近实验值.在MRCI+Q/aug-cc-pV5Z+CV+DK理论水平,用全电子aug—cc—pCVTZ基组计算旋轨耦合修正时得到的旋轨耦合常数为1cm^-1.利用MRCI+Q/aug-cc-pV5Z+CV+DK理论水平得到的势能曲线,通过求解核运动的振转Schr6dinger方程,计算了无转动SO+离子b4∑-态前20个振动态的G(v),Bv和Dv等分子常数.其值与已有的实验结果一致.本文得到的光谱常数和分子常数达到了很高精度,能为进一步的光谱实验和理论研究提供可靠参考.文中的大部分光谱常数和分子常数均属首次报道.  相似文献   

17.
The neutron total cross-sections of thulium (~(169)Tm) were measured in the neutron energy region from 0.01 eV to 100 eV by using the time-of-flight method at the Pohang Neutron Facility, which consists of an electron linac, a water-cooled tantalum target with a water moderator, and a 12 m time of flight path. Two thulium plates with different thicknesses were used for the neutron transmission measurement. The background level was determined by using a notch-filter of Co, In, and Cd sheets. The present measurement was compared with the previous ones, and a new set of resonance parameters of ~(169)Tm isotope was obtained from the transmission rate by using the SAMMY code, with a comparison with the recommended parameters by Mughabghab.  相似文献   

18.
The neutron total cross-sections of thulium(169Tm) were measured in the neutron energy region from 0.01 eV to 100 eV by using the time-of-flight method at the Pohang Neutron Facility,which consists of an electron linac,a water-cooled tantalum target with a water moderator,and a 12 m time of flight path.Two thulium plates with different thicknesses were used for the neutron transmission measurement.The background level was determined by using a notch-filter of Co,In,and Cd sheets.The present measurement was ...  相似文献   

19.
In this study, removal of Cresol Red (CR), a cationic triphenylmethane dye, by 300 kHz ultrasound was investigated. The effect of additive such as potassium monopersulfate (oxone) was studied. Additionally, sonolytic degradation of CR was investigated at varying power and initial pH. RC can be readily eliminated by the ultrasound process. The obtained results showed that. Sonochemical degradation of CR was strongly affected by ultrasonic power and pH. The degradation rate of the dye increased substantially with increasing ultrasonic power in the range of 20–80 W. This improvement could be explained by the increase in the number of active cavitation bubbles. The significant degradation was achieved in acidic conditions (pH = 2) where the color removal was 99% higher than those observed in higher pH aqueous solutions. The ultrasonic degradation of dye was enhanced by potassium monopersulfate (oxone) addition. It was found that the degradation of the dye was accelerated with increased concentrations of oxone for a reaction time of 75 min.  相似文献   

20.
The effects of high-intensity ultrasonic (HIU) treatment on the functional properties of egg yolk were studied in the present work. After HIU treatment, the emulsifying, foaming and gel properties of the egg yolk solution significantly increased, but the foam stability decreased. SDS-PAGE results showed that there was no obvious change in the protein bands of egg yolk, indicating that the yolk proteins did not undergo covalent crosslinking or degradation. HIU treatment enhanced the zeta potential of egg yolk components in solution and increased the free sulfhydryl content of egg yolk proteins. Moreover, the particle size distribution of egg yolk components in solution changed markedly, and these changes demonstrated that HIU treatment caused the aggregation of yolk low-density lipoprotein and the partial dissociation of yolk granules. These results revealed that HIU treatment could change the aggregation of yolk components, which in turn could influence the solution characteristics of egg yolk, finally resulting in changes to the functional properties of egg yolk.  相似文献   

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