Effect Of Different Pretreatments Research Articles

Effect of simultaneous dual‐frequency ultrasound aided ethanolic pretreatment on drying kinetics, bioactive compounds, antioxidant activity, and physicochemical properties of apple slices using pulsed vacuum dryer

AbstractThis work aims at investigating effect of different pretreatments and varied temperature on the drying kinetics, bioactive compounds, antioxidant activity, microstructure and functional group of apple slices using pulsed vacuum dryer. Pretreated apple slices (Ethanol, US + W, and US + E) dried at varied temperature (60, 70, and 80°C) were analyzed to determine total phenolic content (TPC), total flavonoid content (TFC), 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH+), 2,2‐azino‐bis‐(3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS+), color, microstructure and FT‐IR spectroscopy. The findings revealed that US + E pretreatment significantly (p < .05) decreased drying time (20–33.33%). Activation energy and moisture effective diffusivity were 17.60–29.86 kJ/mol and 1.52–3.60 × 10−8m2/s, respectively. Microstructure evaluation showed disruption of cells structure and microchannels formation but was more prominent in US + E pretreatment with noticeable larger pores and several microchannels. US + E pretreatment retained TPC (64.89–75.75 mg/100 g GAE dw), TFC (45.96–56.25 mg/100 g ER dw), DPPH+(66.85–73.34%) and ABTS+(62.58–71.17%) than Ethanol, US + W, and control and was further corroborated by the observed peaks as revealed by the FT‐IR spectroscopy. Color (L*,a*,b*, whiteness) was better retained by Ethanol and US + E pretreatments. US + E pretreatment decreased drying time and also preserved bioactive compounds, antioxidant activity and color of apple slices.Practical applicationApples are popularly consumed fruits and confer various nutritional and health benefits to humans. Drying is the most common approach for apple processing and shelf life extension. However, drying often leads to a reduction in quality parameters as well as degradation of nutritional components of the apple. Novel pretreatment techniques like ultrasonic aided ethanolic pretreatment preceding to apple drying provides an added advantage over conventional drying methods in that it reduces dehydration time as a result of faster moisture removal, lowers energy consumption, improves process efficiency leading to industrial competiveness and it also preserves the nutritional and sensorial parameters of dried apple slices.

Use of high and ultra-high pressure based-processes for the effective recovery of bioactive compounds from Nannochloropsis oceanica microalgae

In this study, the recovery of different bioactive compounds from Nannochloropsis oceanica biomass is proposed using high and ultra-high pressure-based processes. The effect of different pretreatments to weaken cell wall was evaluated before pressurized liquid extraction (PLE). PLE was optimized using an experimental design with ethanol as extraction solvent. Optimum extraction conditions were found at 57 °C and 3 extraction cycles, providing a total carotenoids content of 115.1 ± 0.6 mg/g extract. Then, the residual biomass was extracted using limonene, and an enriched-lipid fraction was obtained. In parallel, ultra-high pressure extraction (UHPE) was applied directly to dry biomass to simultaneously disrupt the cell wall and extract the valuable compounds. Results showed that UHPE technique did not improve carotenoids extraction compared to PLE, although the recovery of polyunsaturated fatty acids was significantly better. Moreover, extracts were chemically characterized using high-performance liquid chromatography detection and gas chromatography coupled to mass spectrometry detection.

Effect of Different Pre-Treatments on Germination Indices and Chromosomal Aberrations of Aged Onion Seeds (Allium cepa)

Effect of Different Pre-Treatments on Germination Indices and Chromosomal Aberrations of Aged Onion Seeds (Allium cepa)

Effects of different pretreatments on the pore structure of Chinese yam during microwave freeze drying.

In order to explore the effects of different pretreatments on the pore structure of Chinese yam during Microwave Freeze Drying (MFD), the samples were treated by typical drying pretreatments including osmosis, blanching and ultrasound, and compared with the untreated samples. The results showed that the pretreatment had significant impacts on the porosity of MFD Chinese yam. Ultrasonic pretreatment could obtain the highest open porosity, and the internal pore network structure of the material showed a uniform sponge shape. The shape of pores obtained by blanching pretreatment was the most irregular. The pore network structure obtained by different pretreatments could result in various product texture and rehydration, which implied that pretreatment methods should be carefully selected according to actual requirements. All these pretreatments could improve the open porosity of MFD Chinese yam, which result in a better rehydration capability. Among them, ultrasonic treatment is worth further investigating. Keywords: microwave freeze drying, pretreatment, pore network structure, Chinese yam, porosity DOI: 10.25165/j.ijabe.20201304.5605 Citation: Wang H, Duan X, Zhao L J, Duan L L, Ren G Y. Effects of different pretreatments on the pore structure of Chinese yam during microwave freeze drying. Int J Agric & Biol Eng, 2020; 13(4): 232–237.

Red bell pepper (Capsicum annuum L.): Optimization of drying conditions and preparation of functional bread.

The aim of this study was to optimize the drying conditions (pretreatments and drying temperatures) of red bell pepper to obtain red bell pepper powder (RBP) with maximum bioactive retention and assess its potential use as a functional ingredient in bread. The RBP pretreated (blanching + dipping in ascorbic and citric acid solution) and dried at 60°C retained the highest bioactive compounds. Wheat flour blends were prepared with RBP at 0%, 2%, 4%, 6%, 8%, and 10% level of incorporation and among hydration properties, water absorption increased with increasing levels. The prepared breads were assayed for physical, nutritional, bioactive, and sensory characteristics. Bread supplementation with RBP improves its color, mineral, fiber, and bioactive properties. However, the texture of bread becomes hard with the increased level of RBP due to a decrease in specific volume. The significant increment was recorded for bioactive compounds, such as total phenols, antioxidant activity, flavonoids, and carotenoids as the level of powder increased. Bread enriched with 6% RBP showed highest sensory scores (8.45) and index of acceptability (87.83%) as compared to other breads. Thus, RBP acts as a valuable supplement for developing bread with improved nutritional and bioactive constituents. PRACTICAL APPLICATION: This study describes the effect of different pretreatments and drying temperatures for processing of RBP as a functional ingredient in bread, being a staple food around the world. RBP powder is a novel ingredient that improved the nutritional, bioactive, and appearance of bread. Hence, it will be helpful in the utilization of perishable crops like bell pepper and will demonstrate its commercial viability to improve the nutritive value of bakery products.

Pre-treatment of granular rice starch to enhance branching enzyme catalysis

Effects of different pre-treatments of granular rice starch using ethanol (ET) and maltogenic α-amylase (MA), separately or combined sequentially ET→MA, were performed to enable efficient subsequent modification with branching enzyme (BE). The pre-treated samples were characterized with respect to morphology, molecular structure, physicochemical properties and the rate of digestion to amylolytic enzymes. MA produced pores and also eroded the granular surface whereas ET caused coapted granules, noticeable swelling but no pores. Crystallinity and enthalpy of gelatinization dramatically decreased with ET and ET→MA. Subsequent BE catalysis increased the specific surface area, crystallinity, α-1,6-glucosidic linkage ratio and enthalpy. BE catalyzed branching resulted in more intact granules, less swelling capacity, solubility and granular separation as compared to their control. These effects were related to reduced amylolytic susceptibility. Pre-treatment prior to BE catalysis offers an efficient alternative way to modify granular starch with different structure and properties depending on the pre-treatment protocol.

Effects of different treatments on seed dormancy breaking and germination in Acer cappadocicum Gleditsch var. cappadocicum

This study was carried out to determine effects of different pretreatment on seed germination and to overcome dormancy in Acer cappadocicum seeds. The seeds were collected in 2008 three times with aproximately 15-days intervals. In order to overcome dormancy, several germination treatments were applied. The treatments were (1) different seed collection time, (2)soaking in water, (3) cold-moist stratification and (4) GA<sub>3</sub> (gibberellic acid) application. The treated seeds were germinated in growing chamber at 5 <sup>0</sup>C and in greenhouse conditions. This research showed that seeds of Acer cappadocicum exhibit physiological dormancy and require stratification period to overcome seed dormancy. The highest germination percentage in the growing chamber subjected to GA<sub>3</sub> process after eight weeks of stratification treatment was 62 % for Acer cappadocicum seeds. The highest germination percentage in greenhouse was obtained with cold stratification after eight weeks (95 %). It was found out that GA<sub>3</sub> treatment had a significant effect on germination in growth chamber + 5 <sup>0</sup>C but GA<sub>3</sub> treatment didn’t have a significant effect on germination in greenhouse conditions. GA<sub>3</sub> treatment and soaking of unstratified seeds in water for 48 hr didn’t have any positive effect on germination value in greenhouse conditions. Although growth chamber and green house results both indicated that seed collection time did not seem to play a role as statistically on seed germination, Duncan’s test showed that the third seed collection time was in a different group.

The effects of different pre-treatments on the physicochemical composition and sensory acceptability of ‘Kacang Koro’ energy bar

Every good food comes with its negative side, and ‘Kacang Koro’ is one of them. Although ‘Kacang Koro’ contains a lot of protein, it also has a negative side, such as an anti-nutritional factor. These anti-nutrient factors need to be removed in order to produce nutritious food. This study was aimed to determine the effect of pre-treatment (soaking, soaking-boiling, soaking-roasting, soaking-microwave) on physicochemical composition and sensory acceptability in ‘Kacang Koro’ energy bar. The energy bars were subjected to physical analyses, proximate analysis, calorie content, phytochemical analyses and sensory analysis. All the different treatments of ‘Kacang Koro’ energy bar showed moisture content of 8.29 - 12.42%, ash of 1.09 - 1.11%, crude protein of 7.51 - 10.14%, crude fat of 12.75 - 17.77%, crude fibre of 2.78 - 3.62%, and carbohydrate of 57.19 - 63.91%. The calorie content was found to be 484.81 - 511.29 kcal/100 g. The oxalate content in all ‘Kacang Koro’ pre-treated is ranged between 29.81 - 45.1 mg/kg. The phytic acid content is between 0.15% - 0.37% and the tannin content is in the range of 25.53 L - 52.30 mg GAE/L. Energy bar with soaking-microwave pretreated ‘Kacang Koro’ has higher value in crude protein, crude fat, and crude fibre but moderate in moisture and carbohydrate content, meanwhile lower in ash content. Sensory acceptability tests showed the sweetness, taste and overall acceptability of the samples were significantly different between ‘Kacang Koro’ energy bars using soaking compared to soaking-microwave pretreatment. The pre-treatment of ‘Kacang Koro’ may boost the use of these ‘Kacang Koro’ in the food industry and promote their application.

Indigofera zollingeriana'nın Tohum Çimlenmesinde Ön İşlem Etkisinin İyileştirilmesi

Indigofera zollingeriana is one of Indigofera species distributed in Indonesia and known as forage crop. Seed is an important factor which influences cultivation of I. zollingeriana due to low seed germination. The objective of the research was to determine the effect of different pre-treatment as chemical scarification (98% of H2SO4, 0.3% of KNO3, glycerine (C3H8O3) at 70oC), hot water at 70oC with different duration of immersion or soaking and mechanical scarification using sand paper on I. zollingeriana’s seed germination. Pre-treatment had significant differences and improved germination percentage, germination speed index and shoot length. The positive correlation was noted between germination percentage and germination speed index.

Effect of different pre-treatments on seed germination of Prosopis juliflora and Dalbergia sissoo: a step towards mutation breeding

For improving the seed germination of Prosopis juliflora and Dalbergia sissoo different treatments were tested, including side cutting, abrasion, overnight soaking in boiling water, scalding in actively boiling water for <br />1 minute and immersion in 30%, 60% and 95% H<sub>2</sub>SO<sub>4</sub> solution. Results showed that abrasion with sandpaper and side cutting were the most effective methods to break seed dormancy in both species, while scalding in actively boiling water for 1 minute, overnight soaking and different concentrations of H<sub>2</sub>SO<sub>4</sub> gave low to zero seed germination. Based on the positive effects of scarification it was concluded that seed dormancy in both species was due to water impermeability of the seed coat. Mutation breeding involves the treatment of large quantities of seeds, therefore abrasion with sandpaper was the most efficient and less labour-intensive method; this method was subsequently used for determination of LD<sub>50</sub> as it is a prerequisite in a mutation breeding program. Abrasion before irradiation had a positive effect on P. juliflora whereas it had a negative effect on D. sissoo seeds. Seeds of both species were exposed to different doses of gamma rays such as 0, 100, 200, 300, 400 and 500 Gy using a <sup>60</sup>Co source. The LD<sub>50</sub> for P. juliflora was 651 Gy based on the rate of seed germination indicating that P. juliflora had tolerance to irradiation and low radiosensitivity to gamma ray. A high LD<sub>50</sub> of 1097 Gy was observed for D. sissoo, suggesting high tolerance to irradiation and very low radio sensitivity. These findings will help to initiate a mutation breeding program in both species to obtain desirable mutants with desirable characteristics such as thornless genotypes, better tree form, disease resistance and increased genetic diversity.

One-Step or Two-Step Acid/Alkaline Pretreatments to Improve Enzymatic Hydrolysis and Sugar Recovery from Arundo Donax L.

Energy crops are not easily converted by microorganisms because of their recalcitrance. This necessitates a pretreatment to improve their biodigestibility. The effects of different pretreatments, as well as their combination on the enzymatic digestibility of Arundo donax L. were systematically investigated to evaluate its potential for bioconversion. Dilute alkaline pretreatment (ALP) using 1.2% NaOH at 120 °C for 30 min resulted in the highest reducing sugar yield in the enzymatic hydrolysis process because of its strong delignification and morphological modification, while ferric chloride pretreatment (FP) was effective in removing hemicellulose and recovering soluble sugars in the pretreatment stage. Furthermore, an efficient two-step ferric chloride-alkaline pretreatment (FALP) was successfully developed. In the first FP step, easily degradable cellulosic components, especially hemicellulose, were dissolved and then effectively recovered as soluble sugars. Subsequently, the FP sample was further treated in the second ALP step to remove lignin to enhance the enzymatic hydrolysis of the hardly degradable cellulose. As a result, the integrated two-step process obtained the highest total sugar yield of 420.4 mg/g raw stalk in the whole pretreatment and enzymatic hydrolysis process; hence, the process is a valuable candidate for biofuel production.

Enhancing swine wastewater hydrolysis with thermophilic bacteria and assisted pretreatments.

Slow degradation rate of swine wastewater, which is mainly caused by particulate and refractory organic matters, is the main drawback of anaerobic digestion. Therefore, it is necessary to improve the hydrolysis of swine wastewater. In this study, different pretreatments were used to hydrolyze swine wastewater, including thermophilic bacteria (TB), alkali, acid, ultrasound (UL), and ultrasonic-combined thermophilic bacteria (UL-TB) pretreatment. The hydrolysis effect was investigated by analyzing the changes of pretreated soluble chemical oxygen demand (SCOD), soluble protein, and carbohydrate. The experimental results showed that effect of different pretreatments on swine wastewater hydrolysis had the following order: TB=alkali>UL-TB>UL>acid. Alkali pretreatment was effective for the release of protein from swine wastewater, and TB pretreatment was advantageous for carbohydrate release during hydrolysis. The results could provide valuable information for the disposition of swine wastewater as well as the application of TB-related pretreatments. PRACTITIONER POINTS: TB and alkali pretreatment exhibited the highest hydrolysis ability. The release of carbohydrate by TB was higher than other pretreatments. Ultrasonic assistance generated inhibition on the hydrolysis of TB.

Physicochemical and nutraceutical properties of tomato powder as affected by pretreatments, drying methods, and storage period

ABSTRACT This study was carried out to evaluate the effect of different pretreatments, drying methods, and storage period on physicochemical and nutraceutical properties of tomato powder. The results revealed that freeze-dried tomato powder showed significantly (p < .05) higher ash, total sugar, reducing sugar, ascorbic acid, lycopene, β-carotene, lightness (L*), redness (a*), and yellowness (b*) values than hot-air-dried samples. However, pH, titratable acidity, and TSS (oBx) showed non-significant difference (p > .05) between hot-air- and freeze-dried samples. Comparing the different pretreatments sodium metabisulphite 1% treated sample (T2) showed highest total sugar, reducing sugar, rehydration ratio, TSS (oBx), lightness (L*), redness (a*) and yellowness (b*) values than non-pretreated samples (T0) and 0.5% ascorbic acid + 0.5% citric acid-treated samples (T1). While T1 showed the highest ascorbic acid, lycopene, and β-carotene contents than T2 and T0. The results obtained indicated that TSS (oBx), pH, total sugar, reducing sugar, rehydration ratio, ascorbic acid, β-carotene, lycopene, and color parameters (L*, a,* and b*) of both freeze-dried and hot-air dried powdered samples showed decreasing trend, while moisture and titratable acidity showed an increasing trend with the advancement of storage period from 0 to 30 days.

Effect of ethanol-wet bonding on porosity and retention of fiberglass post to root dentin.

This in vitro study aimed to assess the effects of different pretreatments used to adapt glass-fiber posts cemented to root canals with different resin cements, regarding porosity percentage and bond strength. Twelve bovine incisor roots were prepared with Largo drills. After post space preparation, the specimens were randomized into two types of pretreatment groups (n = 3): water-wet bonding and ethanol-wet bonding. After the post were cemented, the roots were stored in 100% humidity at room temperature for 7 days. The samples were scanned by microcomputed tomography (micro-CT). Images were reconstructed by NRecon software, and CTAn software was used to analyze the porosity percentage (%) at the luting interface. Evaluation of the push-out bond strength was performed by serially cutting the roots, and submitting the slices to testing. Additionally, the resin cement post-gel shrinkage values (%) were measured using the strain-gauge method (n = 10). Data were analyzed by two-way ANOVA, Tukey's test and Student's t test (a = 0.05). The roots prepared with ethanol-wet bonding using RelyX™ U200 had significantly lower porosity in the coronal and apical thirds (p < 0.05). The group prepared with ethanol-wet bonding using RelyX™ ARC presented better bond strength results in the coronal and apical thirds (p < 0.05). RelyX™ ARC (0.97%) produced a higher post-gel shrinkage value than RelyX™ U200 (0.77%). Canals pretreated with ethanol-wet bonding presented better outcomes in regard to porosity percentage and push-out bond strength.

Effects of different pretreatments on physicochemical properties and phenolic compounds of hawthorn wine

ABSTRACT The physicochemical properties, organic acid, and phenolic profiles of hawthorn wines prepared by different pretreatments were analyzed. It was found that fermentation together with smashed seeds was favorable for ethanol production, while thermal maceration, addition of pectinase and amyloglucosidase significantly increased the levels of sugar-free extract, residual sugar, total phenolics, flavonoids, and most individual phenolic comounds, showing beneficial effects on improving nutritive value of hawthorn wine. Addition of pectinase and amyloglucosidase caused an increase of methanol content by 34.88% and 26.97%, respectively, while thermal maceration decrease the methanol content by 36.20%. Addition of amyloglucosidase yielded the highest contents of procyanidins as well as flavanols, while thermal maceration and addition of pectinase were favorable for improving phenolic acid level. All the pretreatments significantly increased the contents of succinic acid and malic acid in the final wines, among which thermal maceration and addition of pectinase yielded the highest content of succinic acid and malic acid respectively.

Effects of different pretreatments on the pore structure of Chinese yam during microwave freeze drying

Effects of different pretreatments on the pore structure of Chinese yam during microwave freeze drying

Effect of Different Processing Methods on Phytochemical Contents and Neuroprotective Activity of Camellia euphlebia Leaves Extract.

Camellia euphlebia is a new food source and traditional folk medicine in China. Previous studies have demonstrated the antidepressant activity of Camellia euphlebia extract by both in vivo and in vitro experiments. The effects of different pretreatments on phytochemical contents and neuroprotective activity of Camellia euphlebia extract were further investigated in order to develop an optimal processing method that makes the extraction more efficient. Six different powders of Camellia euphlebia leaves were prepared by different pretreatments. The particle size and morphology were examined by using a Malvern particle size analyzer and scanning electron microscopy, respectively. The results showed that the percentage of powder particle size within a range of 0.2∼40 μm was up to 79.18% after press-shear assisted interaction technology pretreatment by 2% addition of shellfish shell powder, and the cells were broken completely. Additionally, the contents of flavonoids, polysaccharides, polyphenols, saponins, and catechin in the extract were 11.78 ± 0.62%, 34.60 ± 3.37%, 6.15 ± 0.29%, 9.43 ± 1.19%, and 1.99 ± 0.11%, respectively, which were higher than those of the other five extracts. Moreover, the extract had the strongest neuroprotective activity by comparing the neuroprotective effect of different extracts on corticosterone-induced neurotoxicity in differentiated PC12 cells. It is concluded that press-shear assisted interaction technology with 2% addition of shellfish shell powder pretreatment, to a great extent, improved the dissolution of bioactive ingredients in Camellia euphlebia.

Effect of Novel Ultrasonic- Microwave Combined Pretreatment on the Quality of 3D Printed Wheat Starch-Papaya System

This study was aimed at investigating the effect of novel ultrasonic-microwave combined pretreatment on the three-dimensional (3D) printing quality of wheat starch-papaya system. In this study, microwave heating (MH) and ultrasonic- microwave combined heating (UMCH) were used as pretreatment in order to gelatinize the system so that it can be printed. During the heating process, the effects of different pretreatments (MH and UMCH) and different low microwave power (60 W, 70 W and 80 W) were compared in terms of the gelatinization degree, rheological properties, dielectric properties, water status distribution, texture, microstructure and printing accuracy. The results showed that when the microwave power was 80 W, the printing effect of samples pretreated by UMCH was the best. Its support stability, line uniformity, and height retention were relatively at an optimum level.

Effect of Different Pretreatments on the Development of Oyster Mushroom Powder and its Utilization in Cookies Formulation

Effect of Different Pretreatments on the Development of Oyster Mushroom Powder and its Utilization in Cookies Formulation

Highly Active Catalysts Based on the Rh4(CO)12 Cluster Supported on Ce0.5Zr0.5 and Zr Oxides for Low-Temperature Methane Steam Reforming

Syngas and Hydrogen productions from methane are industrially carried out at high temperatures (900 °C). Nevertheless, low-temperature steam reforming can be an alternative for small-scale plants. In these conditions, the process can also be coupled with systems that increase the overall efficiency such as hydrogen purification with membranes, microreactors or enhanced reforming with CO2 capture. However, at low temperature, in order to get conversion values close to the equilibrium ones, very active catalysts are needed. For this purpose, the Rh4(CO)12 cluster was synthetized and deposited over Ce0.5Zr0.5O2 and ZrO2 supports, prepared by microemulsion, and tested in low-temperature steam methane reforming reactions under different conditions. The catalysts were active at 750 °C at low Rh loadings (0.05%) and outperformed an analogous Rh-impregnated catalyst. At higher Rh concentrations (0.6%), the Rh cluster deposited on Ce0.5Zr0.5 oxide reached conversions close to the equilibrium values and good stability over long reaction time, demonstrating that active phases derived from Rh carbonyl clusters can be used to catalyze steam reforming reactions. Conversely, the same catalyst suffered from a fast deactivation at 500 °C, likely related to the oxidation of the Rh phase due to the oxygen-mobility properties of Ce. Indeed, at 500 °C the Rh-based ZrO2-supported catalyst was able to provide stable results with higher conversions. The effects of different pretreatments were also investigated: at 500 °C, the catalysts subjected to thermal treatment, both under N2 and H2, proved to be more active than those without the H2 treatment. In general, this work highlights the possibility of using Rh carbonyl-cluster-derived supported catalysts in methane reforming reactions and, at low temperature, it showed deactivation phenomena related to the presence of reducible supports.