Effect Of Ultrasound Pretreatment Research Articles

Effect of ultrasound pre-treatment on ultrafiltration performance in obtaining phenolic compounds from wine production wastes

Effect of ultrasound pre-treatment on ultrafiltration performance in obtaining phenolic compounds from wine production wastes

Correlation of Viscoelastic Properties with Water Status of Scallop Adductors During Heat Pump Drying: Effects of Ultrasound Pretreatment and Drying Conditions

Correlation of Viscoelastic Properties with Water Status of Scallop Adductors During Heat Pump Drying: Effects of Ultrasound Pretreatment and Drying Conditions

Effects of ultrasound pretreatment on flavor characteristics and physicochemical properties of dry-cured ham slices during refrigerated vacuum storage

The application of ultrasound to dry-cured ham may be an option to improve the flavor of meat products storage at vacuum for long periods of time. To investigate the ultrasound-induced influence on flavor characteristics of ham, slices of 9 and 12 months of processing were vacuum packaged and stored at refrigerated temperatures up to 40 d to study the changes of volatile compounds by using solid phase micro-extraction (SPME) and GC-MS and their sensory profile by free choice profile (FCP). Besides, the changes in physicochemical properties (pH, humidity, water activity, color and composition) after ultrasound and storage were determined. Results showed that ultrasound changed the flavor profile of ham slices especially in 12 m hams and after 40 d of storage, with decreased level of linear and Strecker aldehydes and increased level of ketones and alcohols. Sensory results suggested that ultrasound favored the formation of cured and nutty odors with a higher impact in long processing hams (12 m) as observed in the volatile profile as well as increased redness without affecting other physicochemical properties. Therefore, ultrasound is a potential approach to improve the flavor and color characteristics of dry-cured ham slices during vacuum refrigerated storage.

Ultrasound pretreatment enhances moisture migration and drying quality of mulberry via microstructure and cell-wall polysaccharides nanostructure modification

The effects of ultrasound pretreatment (20 kHz, 30 W/L) on mulberries' texture, microstructure, characteristics of cell-wall polysaccharides, moisture migration, and drying quality were investigated over exposure times ranging from 15 to 45 min. Ultrasound induced softening of mulberry tissue, accompanied by an increase in water-soluble pectin and a decrease in chelate-soluble pectin and Na2CO3-soluble pectin concentrations. Noticeable depolymerization of the pectin nanostructure was observed in the pretreated mulberries, along with a decrease in molecular weight, attributed to side-chain structure cleavage. Ultrasound loosened the cell wall structure, increased free water content and freedom, thereby reducing water diffusion resistance. Ultrasound pretreatment reduced drying time by 11.2 % to 23.3 % at various processing times compared to controls. Due to significantly enhanced drying efficiency, the optimal pretreatment time (30 min) yielded dried mulberries with higher levels of total phenolics and total anthocyanins, along with an increased antioxidant capacity. The results of this study provide insights into the mechanisms by which ultrasound pretreatment can effectively enhance the mulberry drying process.

ULTRASON ÖN İŞLEM UYGULAMASININ DERİN YAĞDA KIZARTILMIŞ TAVUK ŞNİTZELLERİN YAĞ EMİLİMİNE VE KALİTESİNE ETKİSİ

Although deep-fried products are enjoyed by consumers of different age groups, they contain large amounts of oil, which affects product quality and cannot fail to meet the demand for a healthy diet. In this study, the effect of ultrasound pretreatment on the oil absorption and quality of deep-fried chicken schnitzels was investigated. For this purpose, chicken schnitzel samples were subjected to ultrasound pretreatment at different amplitudes (32 and 64%) and times (10, 20, and 30 min) and then deep-fried at 180 °C. Ultrasound pretreatment improved the crispness by reducing the hardness of schnitzel samples and also reduced oil absorption by 36-53%. According to the findings obtained from SEM analysis, ultrasound pretreatment caused collapses and deformations in the microstructure of the schnitzel samples, leading to the formation of many microscopic channels. Also, ultrasound pretreatment kept the original sensory properties of the schnitzel samples. These results show that ultrasound pretreatment has greatly improved the quality of chicken schnitzels.

Effects of ultrasound pretreatment on the enzymolysis of hybrid sturgeon (Huso dauricus × Acipenser schrenckii) protein and the structural, functional, and antioxidant properties of hydrolysates

In the current study, hybrid sturgeon hydrolysates were prepared using ultrasound (US) pretreatments for different periods (0, 15, 30, and 45 min) followed by an enzymolysis process using compound proteinase, and their structural, functional, and antioxidant properties were examined. The application of US pretreatments significantly increased the hydrolysis process. SDS-PAGE analysis revealed that as sonication time was increased, peptides with lower molecular weights were obtained. Based on US pretreatment time, hydrolysates demonstrated significant changes in free amino acids, solubility, emulsifying properties, surface hydrophobicity, and water-oil holding ability. Furthermore, US pretreatments had a significant impact on the antiradical activity (DPPH• and ABTS•+) at different hydrolysate concentrations. Partial least-squares regression (PLSR) analysis revealed a positive relationship between most hydrolysate properties and the degree of hydrolysis. These findings indicated that using US pretreatments would be a promising procedure for improving the functional, structural, and antioxidant properties of hybrid sturgeon hydrolysates, thereby expanding their application in the field of food processing.

Effect of ultrasound pretreatment and soaking time on Quinoa malting.

In this study, malt was produced from quinoa seeds using different ultrasound treatment with different intensities (20%, 60%, and 100%), ultrasound times (5, 10, and 15 minutes), and soaking times (2, 6, and 10 hours) at a frequency of 20 kHz. The seeds were soaked in water at 25°C during exposure to ultrasound waves. The results showed that an increase in soaking time led to a higher malting yield and percentage of soluble solids (°Brix), followed by a downward trend. This trend was intensified by longer exposure to ultrasound waves at higher intensities. The interaction effect of ultrasound wave and soaking time on physicochemical properties showed a downward trend, followed by an upward trend in cold-water and hot-water extract yields, reducing sugar, soluble nitrogen, color, and Kolbach index, with increasing levels of the variables. Finally, quinoa malt treated with an ultrasound intensity of 100% for 15 minutes and soaked for 6hours exhibited the best physicochemical characteristics.

Effect of Ultrasound Pretreatment on the Moisture Migration and Quality of Cantharellus cibarius Following Hot Air Drying.

The effect of different ultrasound pretreatment powers (0-500 W) before hot air drying on the moisture migration and quality of Cantharellus cibarius (C. cibarius) was investigated in this study. The results showed that the ultrasound pretreatment accelerated the drying rate. When the ultrasound power was 400 W, the drying time of C. cibarius was reduced by 18.90% compared with the control group. The low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) results showed that the ultrasound pretreatment increased the water mobility in C. cibarius. The scanning electron microscopy (SEM) results revealed that the ultrasound pretreatment promoted the expansion of intercellular pores. In addition, the rehydration capacity and quality characteristics of the ultrasound-pretreated dried C. cibarius were better than those of the control group. Overall, this study concluded that ultrasound pretreatment is a promising pretreatment method for the hot air drying of C. cibarius products to reduce the total drying time significantly and improve the retention rate of the total phenolics and flavonoids of dried C. cibarius.

Effect of ultrasound pretreatment and drying air temperature on the drying characteristics, physicochemical properties, and rehydration capacity of raisins

Effect of ultrasound pretreatment and drying air temperature on the drying characteristics, physicochemical properties, and rehydration capacity of raisins

The Effect of Ultrasound Pretreatment on Pectin Extraction from Watermelon Rind Using Microwave-Assisted Extraction

Ultrasound pretreatment and microwave-assisted extraction (MAE) techniques were used to extract pectin from watermelon rind. This work investigated the effect of the power and time of pretreatment on the yield and characteristics of the extracted pectin. Imaging studies showed that ultrasonic pretreatment changed the morphology of the raw powder, leading to a greater porosity, and facilitated the extraction process. The highest extraction yield of pectin was 19.08% (w/w), for 5 min of extraction at 500 W ultrasonic pretreatment. Ultrasonic pretreatment affected the degree of esterification and the galacturonic acid content of pectin. The galacturonic acid content of all samples was higher than 69.0%. Extraction pretreatment reduced the surface tension value of the aqueous solution of pectin and affected the foam capacity of pectin and its monosaccharidic composition. The ultrasonic pretreatment caused significant changes in pectin characteristics, such as intrinsic viscosity, viscosity average, molecular weight, ratio of homogalacturonan to rhamnogalacturonan and the water holding capacity. In addition, kinetic studies showed that a kinetic empirical model adequately describes the effect of ultrasonic pretreatment on foam stability and its half-time.

Ultrasonic-assisted enzymatic extraction of sulfated polysaccharide from Skipjack tuna by-products

The effect of ultrasound pretreatment on extraction efficiency of sulfate polysaccharides (SPs) using alcalase from different by-products of Skipjack tuna including head, bone and skin was evaluated. Structural, functional, antioxidant and antibacterial properties of the recovered SPs using the ultrasound-enzyme and enzymatic method were also investigated. Ultrasound pretreatment significantly increased the extraction yield of SPs from all the three by-products compared with the conventional enzymatic method. All extracted SPs showed high antioxidant potential in terms of ABTS, DPPH and ferrous chelating activities where the ultrasound treatment enhanced antioxidant activities of the SPs. The SPs exerted strong inhibiting activity against various Gram-positive and Gram-negative bacteria. The ultrasound treatment remarkably increased antibacterial activity of the SPs against L. monocytogenes but its effect on other bacteria was dependent on the source of the SPs. Altogether, the results suggest that ultrasound pretreatment during enzymatic extraction of SPs from tuna by-products can be a promising approach to improve extraction yield but also bioactivity of the extracted polysaccharides.

Effect of ultrasound pretreatment and microwave vacuum drying in the production of dried poniol fruit

AbstractThis study suggested a combination of microwave and vacuum drying to meet the requirements of preserving the nutritional content of fresh poniol fruit, consuming lower energy, and having a faster drying rate. In this study, the influence of microwave power, vacuum level, and citric acid pretreatment level on the product quality of dried poniol was analyzed. The citric acid pretreatment was conducted in an ultrasonicator bath. The pretreated was dried by changing the microwave power () from 400 to 800 W and the vacuum level () from 300 to 600 mmHg. The quality of the dried product was analyzed in terms of total phenolic content (), antioxidant activity (), total change in color (), and rehydration ratio () of dried poniol fruit. The response range in the sequence was between 22.219–38.361 mg GAE/g, 69.037–92.578 %DPPH inhibition, 23.451–40.148, and 1.38–3.81, respectively, at various combinations of independent variables. The optimal combination of independent variables for maximal recovery of total phenolic content, antioxidant activity, rehydration ratio, and minimal color changes was obtained at 440 W power level, 600 mmHg vacuum, and pretreated with citric acid of concentration .8%. Under the optimum combination of independent variables, the total phenolic content, antioxidant activity, rehydration ratio, and total color change values were 37.904 mg GAE/g, 92.973%, 23.906, and 3.307, respectively. Because of the low temperature in the vacuum process combined with the rapid heating time of microwaves, the results indicate that microwave vacuum drying might be a viable alternative method for improving the quality of dried food products.Practical ApplicationsMicrowave vacuum drying is a technology that uses microwave radiation to generate heat in the absolute pressure range between the triple point of water and atmospheric pressure. Heat is generated in microwave vacuum drying by directly converting electromagnetic energy into kinetic molecular energy. Hence, heat is generated deep inside the product being dried. Because interior temperatures are greater than exterior temperatures, evaporating water is driven to the surface, resulting in higher partial pressure. As a result, the moisture evaporating within the product is released through the pore structure of the macro‐capillary system of the solid material, resulting in a faster drying rate. Since the superficial layer does not dry out completely, the surfaces remain porous. This method results in a superior end product that is also very nutritious with enhanced sensory properties. As a result, this approach is used in the chemical, pharmaceutical, and food industries.

Ultrases Ön İşleminin Mısırın Kurutma Sırasındaki Fiziksel Özelliklerine Etkisi

In this study, the effect of some pre-treatments (conventional and 40 kHz 200 W ultrasound soaking) on corn drying was studied. One-hour pre-treated corn samples were dried at 80, 90 and 100 °C in the laboratory type convective air dryer for 240 min time. The moisture contents and physical characteristics such as length, width, thickness, equivalent diameter, equivalent volume, sphericity, thousand kernel weight and hectoliter weight of pre-treated corn samples at each temperature were analyzed for every 60 min during 240 min drying. When the conventional and ultrasound soaking pre-treatments were compared in the temperature range of 80-100 °C during 240 minutes drying of corn, the changes in the reduction rates in moisture content, thousand-kernel weight, hectoliter weight, equivalent diameter and equivalent volume values were 77-86% and 87-90%, 24-27% and 26-29%, 10-13% and 19-20%, 3-10% and 4-9%, 9-25% and 11-25%, respectively. When the results of the research were analyzed, the effect of ultrasound pre-treatment, drying temperature and drying time on moisture content, dimensions (length, width, thickness), equivalent diameter, equivalent volume, sphericity, thousand kernel weight and hectoliter weight of corn grains were found to be significant (P≤0.05).

Effects of ultrasound pretreatment at different powers on flavor characteristics of enzymatic hydrolysates of cod (Gadus macrocephalus) head

To make better use of cod head (Gadus macrocephalus), a by-product of fish processing, the effects of ultrasound pretreatment on the enzymatic properties and volatile compounds of cod head enzymatic hydrolysates were investigated. The results demonstrated that ultrasound pretreatment at 150–600 W had a positive effect cod head enzymatic hydrolysates. The soluble peptides content of the enzymatic hydrolysates reached the highest value of 5.31 ± 0.16 mg/mL at the ultrasound power level of 450 W, and the content of peptide molecules < 3-kDa was up to 93.96%. The type and relative content of volatile compounds, especially aldehydes, alcohols, and ketones, also increased with the increase the ultrasound power. The electronic tongue results indicated that ultrasound pretreatment reduced bitterness and astringency. The electronic nose results indicated that the hydrogen- and alkane-containing odor components in the hydrolyzed liquid after ultrasound pretreatment differed significantly from conventional enzymatic hydrolysates. In conclusion, ultrasound pretreatment may be applicable as a suitable technology to assist enzymatic hydrolysis of the cod head, and as such, promote the utilization of fish by-products.

Investigation of the effect of ultrasound pretreatment on shrinkage of cornelian cherry during hot air drying

Investigation of the effect of ultrasound pretreatment on shrinkage of cornelian cherry during hot air drying

Effect of ultrasound pre-treatment on carbonaceous copper-bearing shale flotation

Although numerous studies have been implemented on identifying the impact of acoustic waves on mineral beneficiation, its fundamental aspects remain unclear in the literature. The present work, for the first time, systematically investigates the role of ultrasound pre-treatment (UPT) in the carbonaceous copper-bearing shale flotation. To this end, conditioning was carried out at different powers of applied ultrasound. Non-treated and UPT shale flotation tests were performed in the presence of frother (MIBC) and collector (KEX). To analyse particle surface charge variation and collector adsorption properties after application of UPT, zeta potential and ultraviolet–visible spectroscopy measurements were implemented, respectively. The generation of sub-micron bubbles due to the acoustic cavitation was characterised by laser-based particle size measurements. Shale hydrophobicity was determined using the sessile drop and captive bubble techniques.The micro-flotation results showed that the mass recovery increased by 40% at 20 W of applied ultrasonic power. The positive effect of UPT on the copper-bearing shale flotation was related to: i) generation of ultrafine bubbles due to the acoustic cavitation phenomenon and ii) the cleaning effect through transient bubble collapse. However, rigorous ultra-sonication diminished the recoverability of the sample owing to the less intensified number of ultrafine bubbles on the particle surfaces and formation of free H and OH radicals, which led to the oxidation of particle surfaces. These statements were correlated well with the observations of the zeta potential, particle size analysis and quantified ultrafine bubbles. Finally, we briefly highlighted fundamental knowledge gaps in flotation and ultrasound-related issues for future work.

Effect of mono- and dual frequency power ultrasound assisted enzymolysis on the degree of hydrolysis and ACE inhibitory activity of Stevia protein hydrolysates

&#x0D; &#x0D; &#x0D; &#x0D; Purpose: To study the effects of ultrasound pretreatment at different frequencies and working modes, including mono frequency ultrasound (MFU) and dual-frequency ultrasound (DFU), on the degree of hydrolysis (DH) and angiotensin-I-converting enzyme (ACE) inhibitory effect of Stevia protein (SP).&#x0D; Methods: Protein from Stevia leaves was extracted by water (50 g suspended in 1000 mL). The hydrolysis of stevia protein extract (SPE) was carried out using alcalase at 5 % enzyme substrate (E/S) ratio. A study was then carried out to investigate its microstructure and morphology using scanning electron microscopy (SEM).&#x0D; Results: The results showed that ultrasound pretreatment did not increase DH of SP significantly (p &gt; 0.05). However, the highest ACE inhibitory activity of stevia protein hydrolysate was obtained at DFU level (20/50 KHz). Overall, ultrasonic frequency mode had a significant influence on ACE inhibitory activity.&#x0D; Conclusion: The frequency selection of ultrasound pretreatment of SP is essential for the preparation of ACE inhibitory peptide.&#x0D; &#x0D; &#x0D; &#x0D;

Effect mechanism of ultrasound pretreatment on fibrillation Kinetics, physicochemical properties and structure characteristics of soy protein isolate nanofibrils

Self-assembly of soy proteins into nanofibrils is gradually considered as an effective method to improve their technical and functional properties. Ultrasound is a non-thermal, non-toxic and environmentally friendly technology that can modulate the formation of protein nanofibrils through controlled structural modification. In this research, the effect of ultrasound pretreatment on soy protein isolate nanofibrils (SPIN) was evaluated by fibrillation kinetics, physicochemical properties and structure characteristics. The results showed that the optimum ultrasound condition (20% amplitude, 15 min, 5 s on-time and 5 s off-time) could increase the formation rate of SPIN by 38.66%. Ultrasound reduced the average particle size of SPIN from 191.90 ± 5.40 nm to 151.83 ± 3.27 nm. Ultrasound could increase the surface hydrophobicity to 1547.67 in the initial stage of nanofibrils formation, and extend the duration of surface hydrophobicity increased, indicating ultrasound could expose more binding sites, creating more beneficial conditions for nanofibrils formation. Ultrasound could change the secondary and tertiary structure of SPIN. The reduction of α-helix content of ultrasound-pretreated soy protein isolate nanofibrils (USPIN) was 12.1% (versus 5.3% for SPIN) and the increase of β-sheet content was 5.9% (versus 3.5% for SPIN) during fibrillation. Ultrasound could accelerate the formation of SPIN by promoting the unfolding of SPI, exposure of hydrophobic groups and formation of β-sheets. Microscopic images revealed that USPIN generated a curlier and looser shape. And ultrasound reduced the zeta potential, free sulfhydryl groups content and viscosity of SPIN. SDS-PAGE results showed that ultrasound could promote the conversion of SPI into low molecular weight peptides, providing building blocks for the nanofibrils formation. The results indicated that ultrasound pretreatment could be a promising technology to accelerate SPIN formation and promote its application in food industry, but further research is needed for the improvement of the functional properties of SPIN.

Influence of pre‐treatments on the degradation kinetics of chlorophylls in morisa xak (Amaranthus caudatus) leaves after microwave drying

AbstractDrying is one of the complex processes, comprising parallel heat and mass transfer reactions. It extends the shelf life of perishable agricultural produces (like green leafy vegetables) by decreasing the level of water activity. In the present work, hot water and ultrasound pretreatments were conducted, prior to the dehydration of fresh morisa xak (Amaranthus caudatus) leaves by microwave drying for improving color stability. In order to assess the color degradation kinetics of chlorophyll, the impact of drying techniques on hunter color parameters (L*, a*, b*) and total color difference (TCD) has been evaluated. Thermal degradation of chlorophyll of the green leaves followed the first order kinetics and Arrhenius equation was employed to describe the temperature dependence of the reaction rate constant. From the study, the protective effect of ultra sound pretreatment on the color stability of morisa xak leaves prior to microwave drying can be observed.Practical ApplicationsMorisa xak is popular and an important green leaves consumed by North Eastern Part of India. As it has high moisture content, morisa xak leaves has been prone to deterioration during post‐harvest storage. Microwave drying has been preferred over traditional hot air drying method due to its high drying rates and better drying quality. As chlorophyll is the main coloring pigment in green leaves, its deterioration is very common during drying. In the current investigation, different pre‐treatments (hot water and ultra sound) were applied to morisa xak leaves before microwave drying to improve the chlorophyll content. The results of the study indicated that the application of ultra sound pretreatment before microwave drying could be a promising technique in comparison with hot air drying method for drying of green leaves with minimum degradation in chlorophyll.

Effects of ultrasound pretreatment followed by far-infrared drying on physicochemical properties, antioxidant activity and aroma compounds of saffron (Crocus sativus L.)

In the current study, the influence of ultrasound pretreatment followed by far-infrared drying on the drying rate, color difference and microstructure of saffron was investigated. The effect of pretreatment duration (30 and 60 s) and drying temperature (50, 60, 70 and 80 °C) on the main chemical composition, total flavonoid, antioxidant activity and volatile flavor compounds in saffron was also evaluated. The results indicated that the total drying time decreased with the increase of pretreatment duration. Especially at 50 °C, the drying time was reduced by 21.05% after 60 s pretreatment. It could also be found that 30 s ultrasound pretreatment with far-infrared drying at 50 °C was the best combination to obtain a good quality of the dried saffron. Under this condition, the samples had the highest chemical properties and volatile compounds, including crocin Ⅰ (20.78%), crocin Ⅱ (10.41%), flavonoid content (10.84 mg/g), antioxidant scavenging activity (58.92%), and major volatile flavor components (54.52%), as well as the acceptable drying time (35 min) and low color difference (26.32). The results of this study confirmed that ultrasound pretreatment had obvious effects and could be recommended for far-infrared drying of saffron.