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Copyright of Revista Ciencia y Tecnología Agropecuaria is the property of Agrosavia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this article, a black ceramic coating is produced on the surface of 7075 aluminum alloy by plasma electrolytic oxidation (PEO) in a silicate electrolyte containing ammonium metavanadate (NH4VO3). The PEO processed sample is further subjected to hydrothermal treatment (HT) and fluorination treatment (FT) to obtain a superhydrophobic PEO/HT/FT coating. The 21‐day air durability test and the tape stripping test show that the superhydrophobic surface shows excellent air durability and mechanical durability. The antireflection test study shows that the average antireflection of the PEO/HT/FT coating is as high as 96.6% in the wavelength range between 400 and 1000 nm. Furthermore, electrochemical test results show that the corrosion current density of the PEO/HT/FT coating decreases to 2.49 × 10−6 A cm−2, three orders of magnitude lower than the aluminum substrate, and the anticorrosion efficiency is as high as 99.87%. The preparation of PEO/HT/FT coating provides more methods for the wide application of Al alloy in aerospace field. [ABSTRACT FROM AUTHOR]

Pork represents a major fraction of the meat consumed worldwide but only 30% of the blood generated in slaughterhouses is re-used as raw material for food and feed. Innovative technologies and efficient processing strategies capable of generating added-value products from it are now attracting attention. In this study, the hydrolysis of porcine coagulated blood using sub-critical solvent extraction was investigated. Biomass was hydrolyzed using different temperatures (120–210 °C), applying only water (sub-critical water; SCW) or water with a low concentration of alkali (0.1 mol L−1 NaOH) and different reaction times (30–90 min). Resultant hydrolysates were analyzed for crude and soluble protein, peptide profile, and bioactivity by combining protein quantification, antioxidant activity, and fast protein liquid chromatography measurements. Results showed that increasing temperature increases the degree of hydrolysis and that the addition of NaOH enhances the solubilization of peptides with high molecular weights. Also, hydrolysates showed interesting antioxidant activity, being 60 min the time of reaction with best antioxidant activity. Nevertheless, using only water (SCW) as solvent, without chemical additives, allows the delivering of interesting protein-based bioactive fractions. Sub-critical solvent treatment of porcine blood resulted in added-value fractions with potential bioactivities through a simple and environmentally friendly process. [ABSTRACT FROM AUTHOR]

Thermal waters have a global distribution and find extensive therapeutic use. In Morocco, which boasts more than twenty high-quality therapeutic thermal springs, few studies have focused on the quality of these waters. In this context, the present study evaluated the water quality using physicochemical, bacteriological, and radioactive parameters for the Benkachour thermal spring waters in Morocco. The results indicate that all chemicals, bacteriological, and radiological parameters are below the standards, except for global beta activity and temperature, which makes it hyperthermal, with an annual average temperature of 50.54°C. According to the Piper diagram, the water type is chloride-sodium-potassium. On the basis on these results, it was concluded that thermalism in the Eastern region of Morocco, specifically Benkachour in Oujda, can contribute to sustainable tourist development at the national and international levels due to the quality of the parameters analyzed and can be an effective complementary approach in the treatment of low-grade pathologies. The data from this study can serve as a baseline for assessing future changes and defining standards for the quality of hydrothermal baths as well as balneotherapy worldwide. [ABSTRACT FROM AUTHOR]

With the aim of further enhancing the bioactive performance of Ti–6Al–4V, ultrasonic‐assisted microarc oxidation (MAO) and hydrothermal (HT) treatments are combined to produce denser, more uniform hydroxyapatite (HA) crystals on the MAO coating herein. More Ca elements can be deposited on the coating and more TiO2 can be generated to form a thicker coating via ultrasonic assistance. Meanwhile, the MAO coating with ultrasonic assistance avoids the appearance of heterogeneous areas and homogenizes the distribution of elements. Those positive effects of ultrasonic‐assisted MAO coating provide favorable conditions for the subsequent HT treatment to form dense and uniform HA crystals. In vitro experiment shows that the ultrasonic‐assisted MAO coating has a higher number of MG63 cells compared with other samples. Moreover, the formation of HA crystals improves the biological activity of all samples. In the ultrasonic‐assisted sample after HT treatment, denser and more uniform HA crystals on the coating surface result in the higher alkaline phosphatase activity of the sample. [ABSTRACT FROM AUTHOR]

The growing interest in natural compounds is helping to improve the management of agro-industrial by-products such as the date seed as sources of such compounds. In this work, the application of a hydrothermal treatment at 160 and 180 °C for 60 min was studied to achieve the solubilization of its phenolic components and sugars in order to obtain biologically active extracts. The percentage of phenols and total sugars in the final extracts were very similar, at 45 and 25% for the 160 and 180 °C treatments, respectively. The treatment at a higher temperature allowed greater solubilization of other components. The antioxidant activity was measured as free-radical scavenging capacity. For the DPPH• method, expressed as EC50, the results were 0.34 and 0.37 mg/L, the TEAC values for the ABTS• method were 6.61 and 3.28 mg/g dried extract, and the values obtained by the ORAC method were 12.82 and 9.91 mmol Trolox/g dried extract, for 160 and 180 °C, respectively. All these values are higher than those of other plant extracts and extracts obtained using the whole date. Therefore, the date seed is a very important source of phenols, and through thermal and chromatographic processes, it is possible to obtain extracts with high antioxidant activity. [ABSTRACT FROM AUTHOR]

[Display omitted] Short-chain organic acids (SCFAs) are widely used in the chemical and food industries. However, their conventional production relies heavily on fossil raw materials, necessitating sustainable alternatives. Waste activated sludge (WAS) can serve as a renewable feedstock for SCFA production through oxidative hydrothermal pretreatment. Thus, the aim of this work was to optimize the production and recovery of SCFAs from partially oxidised WAS. To achieve this, WAS was treated by wet oxidation (WO) at different temperatures (160–200 °C) and ultrafiltered using ceramic membranes (50 and 1 kDa) to pre-purify the SCFAs. Subsequently, these acids were extracted with different combinations of trioctylamine (TOA), tributylphosphate (TBP) and octan-1-ol in the temperature range 25–50 °C. WO at 160 °C for 240 min maximized the SCFA production, obtaining a concentration of 6.07 g/L, with acetic acid as the main component (28.2 %). Membrane ultrafiltration operating in total recycle mode achieved rejections of 39% for TOC and 73% for colour, with a low SCFA rejection (4%) effectively pre-purifying the SCFAs present in the WAS. The main fouling mechanism was cake formation. The highest extraction yields of SCFAs at room temperature were achieved with a mixture of TOA and TBP at 10 % in octan-1-ol, extracting 34 % of the total SCFAs present in the 1 kDa permeate. Lower extraction yields were obtained with the pre-purified WAS compared to synthetic solutions of SCFAs, showing the detrimental effect of the matrix in liquid–liquid extraction. Increasing the temperature within the range of 25–50 °C generally had a favourable effect on the SCFA extraction. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of hydrothermal treatments (heat-moisture treatment (HMT) and annealing (ANN)) on the physicochemical properties and in vitro digestibility of yam starch and yam flour. Hydrothermal treatments decreased the pasting properties of yam starch and yam flour. Compared with yam starch, HMT significantly (p < 0.05) reduced the pasting viscosities of yam flour. Both HMT and ANN caused an increase of the gelatinization temperatures (T o , T p , and T c) and a decrease of enthalpy (△H). The increasement in ratio of 1047/1022 cm−1 and 995/1022 cm−1 suggested that HMT and ANN resulted in an increase in short-range order. The crystalline pattern of all samples was still A-type, and HMT yam starch exhibited higher crystallinity (26.20%). The most significant inhibition of in vitro digestibility was found in HMT yam flour, with slowly digestible starch and resistant starch contents increasing by 3.73% and 4.40%, respectively. Hydrothermal treatments made the no-starch ingredients in yam flour agglomerate and adhere to starch granules. Confocal laser scanning microscopy showed that the starch being coated or embedded by protein was a possible reason for the differences in physicochemical properties and in vitro digestibility between yam starch and yam flour. [ABSTRACT FROM AUTHOR]

Changes to the molecular properties of lignin over the course of biorefinery processing were investigated by using sweetgum as a feedstock. Hydrothermal pretreatment has been used because it is an economically attractive, green process. Three representative biorefinery lignin preparations were obtained, with about 70 % yield based on raw lignin. The three fractions included soluble lignin adsorbed on resin (XADL), solvent‐extracted lignin (HTCELp), and an additional ball‐milled residual lignin (HTRELp). By comparing the raw and biorefinery lignin preparations, it can be concluded that lignin undergoes both degradation and condensation throughout the various stages of the hydrothermal‐based biorefinery process. The two fractions made soluble by biorefinery processing, XADL and HTCELp, were found to be low‐molecular‐weight degradation products enriched with free phenolic hydroxyl groups. In addition, about 15 % of noncondensed phenolic units were involved in condensation reactions. Quantitative NMR spectroscopy analysis revealed that at least about 28 % of β‐O‐4′ substructures were cleaved. Hibbert's ketones were identified in XADL and HTRELp, which provided evidence of lignin undergoing acidolysis. The contents of β‐5′ and β‐β′ did not change significantly upon biorefinery processing. Finally, episyringaresinol was detected in XADL and HTCELp. It is hoped that these findings will help to further demonstrate the specific effects of biorefinery processing on lignin in hardwood and facilitate its utilization to improve biorefinery economics. [ABSTRACT FROM AUTHOR]

Immature Dolichos bean is popular in the Asian region, which is a potent source of vitamin C, antioxidants as well as other macro and micronutrients. Extending shelf life with retaining maximum quality parameters through hydrothermal treatments (HTT) followed by freezing of immature Dolichos bean were carried out. In particular, samples were undergone HTT (n = 9), cooled at room temperature, packed in HDPE packs and stored in a freezer (-18 °C±2), whereas samples without HTT considered as control. The samples were analyzed for physicochemical, sensory attributes, vitamin C and antioxidant activity after three months of freeze storage. In the case of vitamin C, antioxidant activity and color retention, significant differences (p < 0.05) were observed among HTT samples. HTT resulted in improving the cooking quality, sensory characteristics and retaining fresh like traits especially antioxidant activity and vitamin C in Dolichos bean. The study revealed that higher temperature (85 °C-98 °C) HTT for a shorter period of time (3 min) could be suitable for immature Dolichos bean to retain quality parameters without great loss during storage.

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study was on the comparison of hydrothermal treatments at 170 °C (steam injection) and 220 °C (steam explosion) to solubilize the organic matter contained in residual strawberry extrudate, focusing on phenolic compounds that were susceptible to be extracted and on sugars. After the extraction step, the remaining strawberry extrudate phases were subjected to anaerobic digestion to generate biogas that would compensate the energy requirements of the suggested hydrothermal treatments and to stabilize the remaining waste. Hydrothermal treatment at 220 °C allowed the recovery of 2053 mg of gallic acid eq. per kg of residual strawberry extrudate. By contrast, after hydrothermal treatment at 170 °C, only 394 mg of gallic acid eq. per kg of residual strawberry extrudate was recovered. Anaerobic digestion processes were applied to the de-phenolized liquid phase and the solid phase together, which generated similar methane productions, i.e., around 430 mL CH4/g volatile solids, after both 170 °C and 220 °C hydrothermal treatments. Considering the latest observation, hydrothermal treatment at 220 °C is a preferable option for the valorization of residual strawberry extrudate (RSE) due to the high solubilization of valuable phenolic compounds that can be recovered.

Asparagus by-products were submitted to hydrothermal treatments to improve their solubility and antioxidant capacity. Four severity conditions were applied (logR& 3.05, 3.64, 4.23, 4.82) and two fractions were isolated from each treatment. The solid fibrous residues were enriched in cellulose, and depleted of hemicelluloses and phenolics. Their antioxidant activities were higher than those presented for asparagus bioactive fibers (81-154 vs 21-26 mmol Tholox/Kg) and did not correlate with phenol content. The soluble liquors were rich in phenolics and also contained changeable amounts of mono-, oligo-, and polysaccharides as a function of severity. The majority of the released oligosaccharides (xylooligosaccharides) are considered as prebiotic and their percentage could be optimized by modifying hydrothermal treatment conditions. This fraction presented very high antioxidant activity (131-232 mmol Trolox/Kg), and had a moderate correlation with phenols. Melanoidins are suggested to be present in both fractions. A new fiber fraction with potential prebiotic activity and high antioxidant activity has been obtained from asparagus by-products. Its high solubility in water and a pleasant flavor broaden its applications in food formulations, [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Hot water treatment (HWT) against Anastrepha ludens was developed achieving 48 °C in the core of grapefruits and holding it for 6 min. After heating, the grapefruits were hydro‐cooled and stored at 23 °C and analyzed for 16 days. The effect of microwave‐assisted HWT (MW‐HWT) on grapefruit quality was analyzed and compared with the quality of fruits treated with HWT and control fruits (without treatment). The physicochemical properties and chemical composition of essential oil were analyzed. RESULTS: MW‐HWT was equivalent to HWT according to accumulated heat calculations, with the advantage of being shorter. Treatments significantly affected the weight, color, maturity index, juice content, firmness, titratable acidity, pH, and ascorbic acid content of the grapefruits (P < 0.05), but had no effect on the total soluble solids (P > 0.05). The major components identified in the essential oil were d‐limonene and β‐myrcene, compounds responsible of the scent of the grapefruits. CONCLUSION: MW‐HWT was shorter (130 min) and had a lesser effect on the quality of the grapefruit when compared with fruits under HWT (188 min duration). Thus, this treatment could be considered as an alternative method against the Mexican fruit fly in grapefruit. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: A detailed design‐of‐experiment (DoE) study to investigate the cause–effect interactions of three process variables, that is, temperature (120–200 °C), holding time (0–30 min), and concentration (1.4–5.0 wt %), on the processing of citrus cellulosic matter using acid‐free microwave‐assisted selective scissoring (Hy‐MASS) is reported. Analysis of variance (ANOVA) showed that post‐microwave processing, the yield of cellulosic matter (25–72 %), decomposition temperature (345–373 °C), and crystallinity index (34–67 %) were strongly affected by temperature. SEM and TEM analyses showed that the isolated cellulosic matter was heterogeneous and consisted of a mixture of micro‐ and nanofibers more akin to microfibrillated cellulose (MFC) at low processing temperatures and tending towards aggregated cellulose nanofibrils (CNFs) and cellulose nanocrystals (CNCs) at higher processing temperatures. The water holding capacity of the processed cellulosic matter (15–27 g H 2 O  g−1) was higher than the original feedstock or previously reported values. The average molecular weight of the cellulosic matter (113.6–1095.9 kg mol−1) decreased significantly by a factor of 10 at operating temperatures above 180 °C, invoking significant scissoring of the cellulosic chains. The process energy input and costs varied between 0.142–0.624 kWh and 13–373 € kg−1, respectively, and strongly depended on the reaction time. [ABSTRACT FROM AUTHOR]

Twenty-five years ago, it was found that a significant fraction of the starch present in foods is not digested in the small intestine and continues to the large intestine, where it is fermented by the microbiota; this fraction was named resistant starch (RS). It was also reported that there is a fraction of starch that is slowly digested, sustaining a release of glucose in the small intestine. Later, health benefits were found to be associated with the consumption of this fraction, called slowly digestible starch (SDS). The authors declare both fractions to be 'nutraceutical starch.' An overview of the structure of both fractions (RS and SDS), as well as their nutraceutical characteristics, is presented with the objective of suggesting methods and processes that will increase both fractions in starchy foods and prevent diseases that are associated with the consumption of glycemic carbohydrates. [ABSTRACT FROM AUTHOR]

Hydrothermal treatment of biomass in the presence of phosphoric acid is proposed for the production of activated carbons (ACs). Interestingly, H3PO4 promotes the fixation of carbon atoms in the solid during hydrothermal treatment, which renders higher preparation yields than those of the conventional impregnation method. Upon carbonisation of the resulting hydrochars at 450 °C, a notable development of porosity is achieved by using a low amount and concentration of phosphoric acid; these conditions are not adequate for conventional activation. The viability of this process for the sustainable production of ACs has been successfully checked in four biomasses of different composition and structures, and ACs of surface areas above 2000 m2 g−1 and tuneable pore size distribution have been obtained. Electrochemical characterisation of ACs prepared at 750 °C in 1 m H2SO4 demonstrates that capacitances of approximately 150 F g−1 with acceptable rate performance can be obtained through this simple method. [ABSTRACT FROM AUTHOR]

Combined treatment with steam and heat was imposed on green Turkey oak (Quercus cerris L.) wood, both for sapwood and heartwood. Steaming was carried out in an autoclave at 100, 120, or 130 °C, and then a portion of the samples was heated in an oven for 2 h at 120 or 180 °C. Extraction with ethanol provided the greatest extractive contents in sapwood, and the extractive quantity decreased as the heating temperature was increased to 180 °C. In contrast, extraction with dichloromethane provided the greatest extractive content in heartwood, and no sizeable differences were found among the various treatments. Lignin amounts increased with rising treatment temperatures combined with steaming at 100 and 120 °C until the greatest value of 31.1% lignin content was reached. However, the lignin content decreased as the steaming temperatures rose to 130 °C. In all the combined treatments, the lignin content was greater in heartwood than in sapwood. Moreover, both steaming and heating applied individually produced no significant effect on lignin content. [ABSTRACT FROM AUTHOR]

Abstract: Standard maize starch (SMS) was hydrothermally treated by three processes; DV-HMT (Direct Vapor-Heat Moisture Treatment), RP-HMT (Reduced-Pressurized Heat Moisture Treatment) and DIC (in French: Détente Instantanée Contrôlée, instantaneous controlled pressure drop). Impact of processes were studied in order to determine the role of added steps of vacuum before and after treatment of starch by live steam at different pressures (1, 1.5, 2, 2.5 and 3bar) on morphological, pasting (Brabender) and rheological properties of SMS suspension. The three treatments tend to modify the physical properties of starch on the same way, but the extent of these modifications depends on the process and on the level presure applied. The intensity of modifications follows this order: DIC>RP-HMT>DV-HMT. This was attributed to the presence of the initial vacuum step (DIC and RP-HMT) which intensified the transfer phenomena and to the mechanical effect induced by the abrupt decompression towards vacuum (DIC) leading to weakness of starch granules. The treatments changed the shape and distribution size of granules. The sizes were shifted towards higher values after the treatment due both to the improvement of swelling capacity of granules and to the presence of agglomerates particles of different sizes as confirmed by scanning electron microscopy. The agglomerates glued together by gelatinized granules were favored by the direct contact of starch with steam during the treatments. The results showed for all treatments, a reduction of the consistency coefficient (k) and of the yield stress (τ 0) of starch suspensions with increasing of process intensity. For severe conditions (3bar), no difference between the treatments was observed; a complete fluidization of starch suspensions (the consistencies were too weak to be detected), τ 0 vanished and the rheological behavior tended to a Newtonian type. Elastic modulus (G′), measured during gelation at 25°C, decreased dramatically (G′<1Pa), that revealed the loss of rigidity and disappearance of granular integrity of starch. [Copyright &y& Elsevier]

Abstract: Tartary buckwheat was subjected to hydrothermal treatments for minimising rutin loss in buckwheat-based foods by water addition. When native buckwheat flour was mixed with water for 60min, the rutin content was distinctly reduced from 3.74g/100g to 0.31g/100g, increasing the amount of quercetin. However, the rutin content remained constant and quercetin was hardly detected in hydrothermally-treated buckwheat flour. Also, when noodles were prepared with wheat and buckwheat flours (7:3, w/w), the noodle samples containing hydrothermally-treated buckwheat flour, showed higher amounts of rutin (more than 0.83g/100g) than the control noodle with native buckwheat flour (0.27g/100g). In addition, the use of hydrothermally-treated buckwheat flour gave less pasting parameters and lower viscoelastic properties. The noodle dough with hydrothermally-treated buckwheat flour also had greater water absorption and development time during mixing while the elongation stress of the noodle dough was reduced. [Copyright &y& Elsevier]

Germination of legumes followed by hydrothermal treatments is an effective mean of improving nutritive value of legumes. The protein content of mungbean, chickpea and cowpea increased by 9-11, 11-16 and 8-11% after germination. A significant ( p ≤ 0.05) decrease in protein content was observed on pressure cooking and microwaving in all three legumes. The carbohydrates decreased by 1 to 3% during soaking and 2 to 6% during germination. A significant ( p ≤ 0.05) improvement in in vitro protein digestibility (IVPD) was observed after soaking as well as after three germination periods. Germination resulted in an increase in IVPD from 15 to 25% in mungbean, 6 to 17% in chickpea and 6 to 17% in cowpea. A significant ( p ≤ 0.05) increase in IVPD was observed when raw sprouts of three legumes were subjected to pressure cooking and microwaving. In vitro starch digestibility (IVSD) increased significantly ( p ≤ 0.05) after germination, the percent increase being 8 to 12% in mungbean, 9 to 11% in chickpea and 10 to 13% in cowpea. The duration of germination had significant ( p ≤ 0.05) effect on IVSD. A significant ( p ≤ 0.05) improvement in IVSD was observed when legume sprouts were subjected to pressure cooking and microwave cooking. [ABSTRACT FROM AUTHOR]

Abstract: Hydrothermal treatment of ZnO nanostructures involves low temperatures (150–200°C) and elevated water vapor pressure for the purpose of the improvement in the material properties. Under such moderate conditions, no significant changes in the morphology would be expected. Nevertheless, such treatment results in a significant change of nanostructured morphologies of ZnO. The observed changes are dependent on the starting material properties and the substrate used for the growth. In the case of Si substrate, hydrothermal treatment results in significant Si contamination of the samples. In terms of the optical properties, improvements are observed only in some cases, while samples with excellent starting optical properties are degraded by the treatment. Mechanisms responsible for the observed changes are discussed. [Copyright &y& Elsevier]

The purpose of the research was to determine the effect of heat-moisture treatment at different phases and temperatures on resistance starch (RS) level on native starches samples of several botanical sources and to evaluate the thermal stability of different granules. Samples of potato, cassava, wheat, and corn starches were moisturized up to 30% wet basis and then treated in a convection oven at 80, 100, and 120°C during 40 and 60 minutes. RS was determined gravimetrically by a modification of Method 991.43 of the AOAC for the determination of total dietary fibre. All samples were submitted to different thermal analysis in a range from 40 to 180°C at 10°C/min. Overall, in the treated samples an increase of RS was observed, being the corn starch sample treated at 120°C and 60 minutes - the one that presented the highest content of RS (4.2%). Other treated samples showed a decrease in the gelatinization enthalpies with the presence of granular fusion, indicating internal re-arrangement, an increase in the gelatinization temperature and the thermo stability below 95°C. [ABSTRACT FROM AUTHOR]

Abstract: Nutritional and antioxidant properties of phenolic compounds are important in relation to human health and palatability of products. 3,4-Dihydroxyphenylglycol (DHPG) is a strong antioxidant found in small amounts in virgin olive oil and table olives, with an antioxidant activity even higher than that of the powerful hydroxytyrosol. The origin of this antioxidant is completely unclear since has never been reported as a free plant metabolite. In this respect possible precursors of DHPG have also been discussed in this study. The presence of soluble compounds that either contain DHPG in their molecular structure or act as substrates for its synthesis has been showed for the first time. The quantities of DHPG recovered in olive drupe tissue by thermal treatment exceed widely the values indicated in the literature, showing the release or formation of additional DHPG from precursors after heating. In addition, DHPG obtained under certain extraction conditions from fresh solid waste of two-phase olive oil extraction systems (alperujo) is its most important phenolic compound. Therefore, the solid olive waste is a good source of this simple monomer phenol. The chemical structure, purity and racemic nature of isolated DHPG were also analysed for the first time by NMR experiments. [Copyright &y& Elsevier]

Abstract: Zirconium doped mesoporous SBA-15 materials with initial Si/Zr ratios of 10 and 20 have been prepared under microwave-hydrothermal conditions using a non-ionic triblock copolymer surfactant as structure-directing agent, as well as zirconyl chloride and zirconium propoxide as two zirconium sources. The effect of a short (5min) and long (1.5h) sol ageing time on the degree of heteroatom incorporation was tested. Changes in the mesopore size and arrangement were monitored with the aid of powder X-ray diffraction (XRD) and gas nitrogen adsorption/desorption at 77K. The degree of Zr incorporation into the silica framework of the final product was inferred from the analysis by energy-dispersive X-ray spectroscopy and compared with the starting value based on the amount of zirconium added to the reaction mixture. In the case of samples with the lowest initial theoretical molar ratio, the synthesis conditions did not affect the degree of heteroatom incorporation into the silica framework and all zirconium could be introduced under the conditions applied. The structure of materials was strongly dependent on the conditions used, and a more regular pore arrangement was obtained for longer maturation stages. The classical hydrothermal synthesis did not result in a significantly higher efficiency in the heteroatom insertion, though microwave-assisted treatment yielded materials with thicker pore walls. Further increase in the amount of zirconium added to the initial gel did not contribute to a greater heteroatom loading in the final product under microwave conditions. [Copyright &y& Elsevier]

Abstract: Samples of rice husks and corn cobs were subjected to hydrothermal treatments in aqueous media under conditions leading to maximal xylooligomer concentration, and the reaction liquors were extracted with dichloromethane (DCM) to assess the type and amount of reaction byproducts with potential application as food ingredients and cosmetics. The identified DCM-soluble compounds were classified in four categories (sugar-derived compounds, lignin-derived compounds, nitrogen-containing compounds and fatty acids). The experimental results were compared with literature data. [Copyright &y& Elsevier]

Abstract: Recent developments on the manufacture, purification and biological effects of xylo-oligosaccharides are reviewed. Xylo-oligosaccharides (XO) can be produced by chemical and/or enzymatic methods from a variety of xylan-containing raw materials, and then refined by physicochemical treatments. Considered as food ingredients, xylo-oligosaccharides have favourable technological properties and cause prebiotic effects derived from their ability to modulate the intestinal function. Besides the effects related to their effects in the large bowel, a range of additional biological activities have been reported for XO. Other topic discussed include the utilization of XO in synbiotic preparations, their technological properties and market perspectives. [Copyright &y& Elsevier]

Abstract: Rice husks were subjected to hydrothermal processing in aqueous medium to cause the degradation of xylan to xylooligosaccharides. The resulting solid phase, with enhanced contents of cellulose and lignin, was assayed as a substrate for enzymatic hydrolysis either directly or after treatments with hydrogen peroxide in alkaline media under a variety of operational conditions. Solid yield, solid composition and susceptibility to enzymatic hydrolysis were assessed by empirical modelling. The susceptibility of the solids to enzymatic hydrolysis was greatly improved by peroxide treatments. Under selected conditions (oxidizing treatments with 50g hydrogen peroxide/100g solids at 80°C for 4h using a liquor to solid ratio of 15g/g) lignin was removed in high proportion, and cellulose was almost quantitatively recovered in solid phase. In the subsequent enzymatic hydrolysis (using an enzyme/substrate ratio of 25FPU/g at liquor to solid ratio of 15g/g for 48h), 67.9% of cellulose was converted into glucose, leading to a medium containing 43.5g glucose/L. Higher cellulose conversions were achieved when the liquor to solid ratio employed in the enzymatic hydrolysis was increased, but then the final glucose concentrations decreased owing to the higher amount of liquid. [Copyright &y& Elsevier]

Abstract: The effect of hydrothermal treatments on the properties of Finger millet starch was investigated. Finger millet was modified by heat-moisture treatment, HMT at 100°C, 16h; 20% moisture level (MHT-20), 25% moisture level (MHT-25) and 30% moisture level (MHT-30) and annealed, ANN at 50°C for 48h (MAN). Results of the pasting characteristics shows that MNS and MAN were indicative of type ‘B’ starch which is characteristic of normal cereal starches, while HMT starches were Type ‘C’ which is characteristics of cross-linked or legume starches. MNS belonged to the type ‘A’ pattern of cereal starches. X-ray diffractometry studies (XRD) show that MNS gave strong peaks centered at 23.5, 20.3, 18.2, 17.15, and 15.15Å, while HMT and ANN starches retained the typical ‘A’ pattern. Scanning electron microscopy (SEM) studies show that the shape and surface characteristics of the starches were irregular, polygonal-shaped granules, with less than 1% cavity or ruptured granules. Modification did not affect the appearance. All the starches swell as the temperature increased in the order MNS>MAN>MHT-20>MHT-25>MHT-30, and solubilized at different rate in the following order: MHT-30>MHT-20>MHT-25>MAN>MNS. The gelation profile of the starches ranged from 4 to 8% (w/v), while its oil and water absorption capacity ranged from 1.90 to 2.50 and 2.75 to 3.25g/g, respectively. [Copyright &y& Elsevier]

Copyright of Boletin Intexter del Instituto de Investigacion Textil y Cooperacion Industrial Terrassa is the property of Universitat Politecnica de Catalunya and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Boletin Intexter del Instituto de Investigacion Textil y Cooperacion Industrial Terrassa is the property of Universitat Politecnica de Catalunya and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Brewery’s spent grain was treated with water in a process oriented towards the production of xylo-oligosaccharides (XOS). A wide range of temperatures and reaction times were tested and the effects of these operational variables on hemicellulose solubilization and reaction products were investigated. The maximal XOS yield (61% of the feedstock xylan) was obtained at 190 °C after 5 min of reaction. Several oligosaccharide mixtures with different molecular weight distributions were obtained depending on temperature and reaction time. Longer reaction times led to decreased oligosaccharide production and enhanced concentrations of monosaccharides, sugar decomposition products and acetic acid. With reaction times leading to the maximal yields of XOS, little decomposition into organic acids and aldehydes was found at all the temperatures assayed. From the composition of processed solids, it was calculated that 63–77% of the initial xylan was selectively solubilized in autohydrolysis treatments. [Copyright &y& Elsevier]

The preparation of heterogeneous catalysts has by now lost all empirical aspects. The approach is scientific and involves a wide number of specific competencies of solid state chemistry, analytical chemistry, physical chemistry, kinetics, rheology, etc. The fundamental aspects in the preparation of heterogeneous catalysts starting from catalyst design up to the catalyst in its final form are briefly reviewed, with focus on the key factors in each preparation step and the main differences between laboratory and industrial scale preparations. The main properties of monolithic catalysts and their preparation methods are also reported, considering their relevance for environmental applications. [Copyright &y& Elsevier]

[Display omitted] • Classification of sludge products from hydrothermal treatments is proposed. • Chemical oxygen demand fractionation and the role of oxygen were studied. • Non-readily biodegradable fraction was twice in absence of oxygen. • Wet oxidation led to higher mineralisation and minimisation of solid fraction. • Oxygen turns intermediates and non-volatile hydroxy acids into volatile fatty ones. As the wide variety of compounds that are solubilised and generated during hydrothermal treatments of sewage sludge cannot be defined individually, this study proposes a classification based on chemical characteristics and biodegradability. Moreover, it has deepened understanding of the role of oxygen in the reaction mechanisms and the evolution of chemical oxygen demand (COD) fractions and their components during hydrothermal treatments (180 °C, 80 bar). This information is necessary before separating specific compounds or using the hydrolysates directly as fertiliser or fermentation media. Results revealed the existence of an initial stage of sludge solubilisation (30 – 60 min), mainly produced by hydrolysis reactions and without mineralisation, followed by a second stage where oxygen promoted the conversion of solubilised compounds, mineralisation and the minimisation of the solid fraction. Total COD and total suspended solids (TSS) were reduced by 48% and 75% after 210 min of wet oxidation, compared to 28% and 50% after thermal hydrolysis. Oxygen led to a final liquid hydrolysate with fewer easily assimilable compounds (38% of the initial total COD converted into readily biodegradable), inorganic elements (17 g/kg TSSo) and refractory, inhibitory and less assimilable compounds (1.1 g O 2 /L of slowly and non-biodegradable COD) compared to that obtained in its absence (61%, 24 g/kg TSSo and 2.3 g O 2 /L, respectively). Oxidation mechanisms favoured the conversion of non-volatile hydroxy acids (NVHA) and intermediate compounds to volatile fatty acids (VFA), with VFA concentration being almost 3 times higher under an oxidising atmosphere, but with NHVFA 57% lower. [ABSTRACT FROM AUTHOR]