Influence Of Ultrasonic Pretreatment Research Articles

Influence of ultrasonic pretreatment on the quality attributes and pectin structure of chili peppers (Capsicum spp.)

Chili peppers (Capsicum spp.) exhibit a diverse range of quality characteristics and pectin structures, which are influenced by various factors. This study aimed to investigate the effects of ultrasound (US), ultrasonic combined hot blanching (US-BL), and ultrasonic combined freezing and thawing (US-FT) on the quality characteristics and pectin structure of vacuum pulsation-dried (VP) chili peppers. The results indicated that US-BL samples exhibited the highest L* and a* values, retained maximum capsorubin, and showed an increase in vitamin C, total phenols, and rehydration by 14.28 %, 40.87 %, and 8.66 %, respectively. In contrast, the US-FT samples exhibited the highest capsaicin and dihydrocapsaicin content, which increased by 54.97 % and 64.04 %, respectively. Pretreatment resulted in higher pectin linearity, a lower degree of branching, and a reduced molecular weight in the US-BL sample. Atomic force microscopy confirmed the degrading effect of pretreatment on the pectin structure. Pearson’s correlation analysis revealed that capsorubin, capsaicin analogs, vitamin C, and total phenols were highly correlated with pectin linearity and molecular weight. This study found that US-BL was the most effective pretreatment method for improving the quality of pulsatile chili peppers and provides theoretical support for the application of VP chili peppers.

Influence of ultrasonic pretreatment on drying and thermodynamic characteristics of Asian seabass fish skin during air-frying process

Influence of ultrasonic pretreatment on drying and thermodynamic characteristics of Asian seabass fish skin during air-frying process

Simulated in vitro gastrointestinal digestion of β-lactoglobulin treated by ultrasound: Detection of peptides profile and the antioxidant activity

The influence of ultrasonic pretreatment on the release and antioxidant activity of potential antioxidant peptides after in-vitro simulated gastrointestinal digestion of β-lactoglobulin (BLG) were measured by HPLC-MS/MS, chemical and cellular-based assays. The gastrointestinal digest was fractionated into four fractions by Sephadex G-25 gel filtration column, and fractions showed a considerable ABTS·+ scavenging ability. The fraction with the strongest antioxidant activity was produced by ultrasonicated BLG after gastrointestinal digestion, which relies on ultrasonic-promoted proteolysis to produce many small-molecule antioxidant peptides. The best active fraction has better cellular antioxidant activity and protection of H2O2-induced oxidative HepG2 cell model, which significantly increases the activities of antioxidant enzyme, and is concentration-dependent. HPLC-MS/MS analysis showed that there were more potential antioxidant peptides in the best active fraction. This research will provide a basis for the further application of ultrasonic in dairy products, which can promote the release of more potential antioxidant peptides-derived from gastrointestinal digestion.

Investigation on the influence of ultrasonic pretreatment on color, quality and antioxidant attributes of microwave dried Inula viscosa (L.)

Impact of various ultrasound pretreatment and microwave drying parameters on the qualitative and antioxidant characteristics of Inula viscosa (L.) was investigated in this study. The leaves of Inula viscosa (L.) were sonicated for 10, 20, and 30 min in an ultrasonic bath (37 kHz, 150 Watts). Microwave drying was done at three distinct times (1, 3, and 5 min) and with three different microwave power levels (100, 180, and 300 Watts). Microwave dried samples were tested for color characteristics (L*, a*, b*), chlorophyll, carotenoid, total phenol, and antioxidant content. All dried samples were prepared by infusing them in hot water as tea, and the sensorial properties of teas including odor, color, aroma, and overall acceptability were evaluated by panelists. For 10, 20, and 30 min of ultrasound pretreatment, the L* values of leaves varied from 37.70 to 49.76, 34.97 to 46.25, and 27.88 to 43.34, respectively. The total carotenoid concentration ranged from 0.12 to 0.32 mg/g DW, while the total chlorophyll content was from 0.44 to 0.94 mg/g DW. The antioxidant activity of Inula viscosa (L.) leaves that were dried at 300 Watts for 5 min did not change significantly as a result of ultrasound pretreatment. There was a significant positive correlation between aroma and TPC, as well as between color and overall acceptability. The darkest-colored teas were deemed preferable by the panelists.

Influence of ultrasonic pretreatment on structural properties and biological activities of lupin protein hydrolysate

SummaryThis study examined how application of ultrasound pretreatment (UP) (400 W, 20 kHz for 5, 10 min) influenced the structural characteristics, molecular weight distribution, amino acid composition and biological activity of hydrolysate prepared from lupin protein using protamex enzyme. Circular dichroism (CD) and Fourier transform infrared (FTIR) techniques revealed changes in secondary structure after UP, while changes in molecular weight pattern were revealed by SDS‐PAGE and MALDI‐TOF analyses. Also, the crystallinity and surface hydrophobicity of the hydrolysates were affected by UP. The amino acid compositions of the hydrolysate varied, especially glutamic acid, arginine and aspartic acid. In vitro biological assays showed that antioxidant, α‐glucosidase, α‐amylase and ACE inhibitory activities significantly improved in sonicated hydrolysates compared with non‐sonicated samples, and this may be linked to the structural modifications caused by UP. Hence, the application of UP to lupin protein could en hance the biological activity of its hydrolysate.

Influence of ultrasonic pre-treatment on Pyrolysis and Combustion of Sewage Sludge by TG

The combustion and pyrolysis processes of sewage sludge were studied in the current report. Two kinds of sewage sludge(SS) were used, SS the sewage sludge was not treated, while SS-U90KHz the ultrasonic bath pre-treated sewage sludge with a frequency of 90KHz was not treated. Wastewater treatment plants are the origins of waste sludge. Analyses were performed roughly and finally. Thermogravimetric research analyzed the thermal behaviour of the analysed sewage bucket (TGA). The samples were heated at a constant rate of 25 to 800 Celsius by air (combustion) and nitrogen flow (pyrolysis). For sludges which have been investigated. In the TG/DTG curves, comparable thermal profiles were available. All of the TG/curves DTG’s were divided into three periods. At the same time, during the combustion stage, the sewage sludge decomposition occurred in the 180-580 0C range. The pyrolysis procedure took place at a lower rate, but less weight loss..

Influence of ultrasonic pretreatment on electrohydrodynamic drying process of goji berry

Influence of ultrasonic pretreatment on electrohydrodynamic drying process of goji berry

Evaluation of Ultrasound Pretreatment for Enhanced Anaerobic Digestion of Sida hermaphrodita

The influence of ultrasonic pretreatment with specific energy input ranging from 25 to 550 kJ/kg volatile solids on the mixture of Sida hermaphrodita (L.) Rusby mixed with cattle manure disintegration and subsequent anaerobic digestion was assessed. The pretreatment process led to significant increase in the biomass solubility by 21.9% as chemical oxygen demand and enhanced biogas yield by 157% (567.1 L biogas/kg volatile solids) when the specific energy input was from 200 to 550 kJ/kg. However, only pretreatments where ultrasound was applied at 25–50 kJ/kg led to positive net energy gain, indicating that the biomass processing with this method does not always compensate the energy consumption for irradiation.

Influence of ultrasonic pretreatment on the structure, antioxidant and IgG/IgE binding activity of β-lactoglobulin during digestion in vitro

The influence of ultrasonic pretreatment on the structure, antioxidant activity, and IgG/IgE binding activity of β-lactoglobulin (β-Lg) during digestion in vitro were studied by spectroscopy, chromatography and ELISA. After β-Lg was treated by ultrasonic prior to digestion in vitro, the treated β-Lg showed high intrinsic fluorescence emission, more of the hydrolytic products and high antioxidant activity, which depend on the proteolysis promoted by ultrasonic, and produced many small-molecule antioxidant peptides. Native β-Lg was resistant to gastric digestion and retained its allergenicity. However, the allergenicity of ultrasonicated β-Lg after gastric digestion was increased due to ultrasonic promotes the production of peptides with intact structure and immunogenicity. Subsequent gastrointestinal digestion, ultrasonicated β-Lg has a diametrically opposite results because the increase of small peptides with the decreasing of immunogenicity. Therefore, the structural changes of β-Lg by ultrasonic and gastrointestinal digestion were responsible for improving the antioxidant activity and reducing the IgG/IgE binding activity.

Influence of ultrasonic pretreatment on the co-pyrolysis characteristics and kinetic parameters of municipal solid waste and paper mill sludge

In this study, through orthogonal experiments design, the influences of ultrasonic pretreatment (frequency, power and treatment time) on co-pyrolysis and catalytic pyrolysis of municipal solid waste and paper mill sludge were explored. The differential thermogravimetry curves became steeper and the peak values were larger after pretreatment, which made the pyrolysis reaction rapidly and the volatile separated out timely. However, the change of pyrolysis characteristics was not obvious after adding MgO. The catalytic effect of MgO increased with the increase of sludge ratio. After pretreatment, the average activation energy of the samples had an overall increasing trend, but the change was small. MgO had a decreasing effect on activation energy, and with the increasing proportion of sludge the degree of reduction became significant. In addition, high ultrasonic frequency had a negative effect on reducing activation energy.

Influence of Ultrasonic Pretreatment with Hot Air Drying on Nutritional Quality and Structural Related Changes in Dried Sweet Potatoes

Abstract The drying of sweet potatoes not only helps to prolong its storage life but the dried form reportedly enriched with high bioactive compounds than regular sweet potatoes. The study aims to investigate the influence of dual-frequency ultrasound pretreatments (40 and 60 kHz) at two different hot air drying temperatures (70 °C and 80 °C) on quality of dried product. Ultrasound pretreatment at 40 kHz with 70 °C maintained the phytochemical compounds in the dried sweet potatoes. Ellagic acid and chlorogenic acid were found as predominant phenolic acids using HPLC analysis, while identification of two new bioactive compounds quercetin-3-rhamnoside and quercetin 3-β-D-glucoside were the novel finding of the current study. A short new band appeared in FTIR in all treatments from 2164 to 2041 cm−1 which refers to C = C alkenes functional group. The multivariate analysis showed a great influence of USH3 and USH1 with a positive relationship with most of bioactive compounds.

Comparative Study of Yield, Chemical Composition and Antioxidant Activity of Wild Algerian Lavandula stoechas L. Obtained by Ultrasound Pre-treatment and by Conventional Hydrodistillation

The paper presents research results concerning the influence of ultrasonic pre-treatment (time intervals of 10, 20, 30, 45, and 60 min) on the process of extraction of essential oils from wild Algerian Lavandula stoechas. Tests were carried out in two populations. A sonication pre-treatment time of 10 min followed by 90 min of hydrodistillation (US-HD) gives a yield of 1.60 ± 0.1% of Kodiat essential oils (KEO). This pre-treatment time proved to be the best when compared with other pretreatment times. However, overall best yield (1.03 ± 0.07%) of El-Kahla essential oils (EEO) was obtained at 60 min of pre-treatment. These yields are higher compared with those (0.64 ± 0.02% and 0.50 ± 0.02%) obtained after 180 min of only hydrodistillation (HD) for the two samples of Lavandula stoechas, respectively. About 90.69% and 89.36% of total compounds were identified using chromatography–mass spectrometry (GC– MS) in KEO and EEO treated by ultrasound versus untreated samples (89.26% and 76%, respectively). A qualitative and quantitative difference in chemical composition between the essential oils of treated and untreated samples of the two harvesting sites was found. The percentage of most of the major compounds (fenchone, camphor, 1,8-cineole, bornylacetate, myrtenyl-acetate, and viridiflorol) and other compounds identified is higher in treated samples. GC/FID (flame ionization detector) analysis of KEO showed that the percentage of fenchone and camphor as major components is greater at 60 and 20 min of ultrasonic (US) pretreatment, respectively, compared with HD and the other US pre-treatment times. Results of the present study clearly indicated that sonication treatments are effective in enhancing the antioxidant activity of Lavandula stoechas extracts and could be further explored for commercial purposes to benefit consumers and the environment.

Energy performance evaluation of ultrasonic pretreatment of organic solid waste in a pilot-scale digester

It has been proven that ultrasonic pretreatment (UP) has positive effect on biogas generation from previous lab-scale studies. However, that is not always the case in larger scale processes. The purpose of this study was to evaluate the effectiveness of UP to biogas generation in terms of anaerobic digestion process and energy efficiency. Parameters including total solids (TS) and ultrasonic treatment operational parameters of organic solid waste (OSW) resulted from our past lab scale UP studies were applied in this study. OSW with 6–10% TS was treated using a lab-scale ultrasonic processor using various power densities (0.2–0.6 W/mL) at different time periods up to 30 min. Results of lab scale confirmed that OSW with 6% TS sonicated with 0.2 W/mL power density in 30 min gave the best outcome for the pilot scale experiment. To simulate the condition of an actual scale, in addition to energy analysis, two different organic loading rates (OLR), namely 500 and 1500 gVS/m3day were examined. The pilot digester was fed with OSW with or without the pretreatment based on the aforementioned specifications. The results showed that UP effectively improves biogas generation in terms of quantity and quality (CH4/CO2). Furthermore, it decreases the time to reach the maximum cumulative biogas volume comparing to the untreated feed. The key achievement of this research has confirmed that although the relative increase in the energy gain by the influence of UP was more remarkable under the 500 gVS/m3day OLR, energy analysis showed a better energy gain and energy benefit as well as jumping in biogas yield up to 80% for UP treated OSW under 1500 gVS/m3day OLR.

Mathematical modeling and influence of ultrasonic pretreatment on microwave vacuum drying kinetics of lotus (Nelumbo nucifera Gaertn.) seeds

ABSTRACTThe people of Southeast Asia often use lotus as a highly sought-after food source. Here, the effects of ultrasonic pretreatment on the drying kinetics of lotus (Nelumbo nucifera Gaertn.) seeds under microwave vacuum drying were investigated. The best fit model to predict the drying kinetics was also proposed. Lotus seeds were subjected to ultrasonic pretreatment at frequencies of 20, 35, and 80 kHz and power intensity of 0.75 and 1.50 W/g for 10 min using an ultrasonic bath and then to microwave vacuum drying. Five different mathematical models were fitted to the experimental data and a newly proposed model was selected based on model with highest regression coefficient (R2), lowest root mean square error (RMSE), sum square error (SSE), and chi-square (χ2), respectively. Time-domain nuclear magnetic resonance and field scanning electron microscope were used to describe the water state of ultrasonic samples and examine microstructure, respectively. The results showed that ultrasonic pretreatment performed at a relatively low frequency and relatively high power intensity had a positive effect on reducing the drying time (6.25–31.25%) during microwave vacuum drying because of the redistribution of water and the formation of microchannels. In parallel studies, the new model showed the best fit to the drying curve.

Influence of Ultrasonic Pretreatment on Deliquoring Properties in Expression of Carrots

Influence of Ultrasonic Pretreatment on Deliquoring Properties in Expression of Carrots

Influence of ultrasonic pretreatment on the yield of bio-oil prepared by thermo-chemical conversion of rice husk in hot-compressed water

The aim of the current study is to investigate the feasibility of thermo-chemical conversion of rice husk in hot-compressed water via ultrasonic pretreatment to increase the bio-oil yield. The results show that ultrasonic pretreatment remarkably changes the structures of the rice husk, such as enhancing swelling and surface area, eroding lignin structure, and resulting in more exposure of the cellulose and hemicellulose. The highest bio-oil yield of 42.8% was obtained from the thermo-chemical conversion at 300 °C and 0 min of the residence time for the 1 h pretreated rice husk. GC-MS analysis indicates that the relative contents of phenols, 5-Hydroxymethylfurfural, and lactic acid are higher in bio-oils obtained from the pretreated rice husks than that from the raw rice husk.

Heterogeneous Preparation of Polyaniline-Cellulose Conductive Composites with Cellulose Pretreated by Ultrasonic and its Electrical Properties

A series of conductive composites polyaniline(PANI)-cellulose were heterogeneously synthesized by chemical oxidative polymerization of aniline with native cellulose pretreated by ultrasonic. The morphology and chemical structure of the composites were examined by SEM and FTIR. TGA was used to study their thermal properties. The electrical conductivity was measured at room temperature by the standard four-probe method. For the sake of illuminating the influence of ultrasonic pretreatment on the structure and properties of PANI-cellulose composites, the SEM microphotographs, FTIR spectrum and TG curve of the PANI-cellulose composites prepared with native cellulose without any treatment were also shown in this paper to serve as reference. The PANI content and electrical conductivity of these two composites were also compared. It was found that cellulose surface was severely eroded by ultrasonic wave, and PANI homogeneously dispersed on this eroded cellulose surface in the form of particles. In reverse, the PANI particles loaded on the surface of untreated cellulose with evident aggregation. The homogeneous dispersion of PANI particles would be favor for the improvement of the electrical conductivity of the composites. From the FTIR spectra, it was verified that there was no difference between these two composites. It indicated that ultrasonic force did not lead to the variation of the chemical structure of cellulose. TG curves revealed that the thermal stability of PANI-cellulose composites was obviously enhanced than pure cellulose due to the protection of PANI particles deposited on its surface. Nevertheless, ultrasonic has a negative effect on the thermal stability of the composites, which resulted in the long cellulose molecular chains change into shorter ones, so the decomposition of composite occurred at lower temperature. It was because that ultrasonic pretreatment contributed to the homogeneous dispersion of PANI and more PANI particle depositing on the cellulose surface. Therefore, the PANI-cellulose composites with ultrasonic pretreated cellulose have more PANI content and higher electrical conductivity than the composites with untreated cellulose. Moreover, the difference of these two factors between the two composites became more and more marked with increasing of the amount of aniline. When aniline used was up to 0.5 g, the PANI content in the former was 48.2% more than the latter. This work provided a facile method for the synthesis of PANI-cellulose conductive composites with excellent conductivity.

00/00712 Influence of ultrasonic pretreatment on the coal liquefaction

00/00712 Influence of ultrasonic pretreatment on the coal liquefaction