•Hydrothermal process is an effective fractionation process for Sargassum.•Pretreated Sargassum was subjected to cellulases and hemicelluloses enzymes.•Stirred tank and bubble column bioreactor were ...performed for PSSF and SSF.
Sargassum spp. is a biomass that can potentially use as an alternative for bioethanol production. Hydrothermal processes (liquid hot water and steam explosion pretreatment) were carried out at different operational conditions. Enzymatic hydrolysis performed a preliminary test with different ratios 1:1 and 1:2 (cellulases and hemicellulases) of enzyme loading, once selected 1:2 ratio was obtained conversion yield of 99.91% and therefore carried a scale-up in stirred bioreactor getting 95.92% saccharification yield. Pre-simultaneous saccharification and fermentation strategy was performed in a continuous stirred tank bioreactor (CSTBR), producing ethanol yield of 57.69%, and for simultaneous saccharification and fermentation strategy was performed in a bubble column reactor was 71.37% ethanol yield. The energy efficiency was analyzed in different scenarios; the best data was 30.19 (gsugar/MJ) in the bioreactor enzymatic hydrolysis process. This development allows for establishing the conditions for a third-generation biorefinery on a circular bioeconomy using Sargassum biomass.
The maintenance of buildings has become an important issue with the construction of many high-rise buildings in recent years. However, the cleaning of the outer walls of buildings is performed in ...highly hazardous environments over long periods, and many accidents occur each year. Various robots are being studied and developed to reduce these incidents and to relieve workers from hazardous tasks. Herein, we propose a method of spraying high-pressure water using a pump and nozzle, which differs from conventional methods. The cleaning performance parameters, such as water pressure, spray angle, and spray distance, were optimized using the Taguchi method. Cleaning experiments were performed on window specimens that were contaminated artificially. The cleaning performance of the proposed method was evaluated using the image-evaluation method. The optimum condition was determined based on the results of a sensitive analysis performed on the image data. In addition, the reaction force due to high pressure and impact force on the specimens were investigated. These forces were not sufficient to affect the propeller thrust or cause damage to the building's surface. We expect to perform field tests in the near future based on the output of this research.
Summary
High‐pressure extraction was used to produce pomegranate peel extract, later incorporated in carrot juice. Chemical, microbiological and sensorial analyses were performed during storage to ...untreated, high‐pressure and thermally processed juices incorporating pomegranate peel extract. Fortified juices showed lower counts for mesophiles and psychrophiles than the nonfortified ones (P < 0.05). Total phenolic and hydrolysable tannin contents, and antioxidant activity had superior values in supplemented juices during storage. The extract did not affect any sensorial parameter. On the 28th day, pressurised juices exhibited lower microbial loads in comparison with heated process, but phenolic compounds, antioxidant activity and several sensorial descriptors were identical between both processing technologies. The β‐ and α‐carotene content decreased after processing, and pressurised juices exhibited higher residual activity for peroxidase (P < 0.05). These data suggest that the application of pomegranate peel extract in treated carrot juices (2.5 mg mL−1) improves their microbial safety and antioxidant capacity, without impairing the sensorial aspects.
Development of a beverage with improve antioxidant properties: microbiological studies and consumer acceptance.
The effect of high pressure thermal (HPT) treatments on the inactivation of spores of non-proteolytic type E Clostridium botulinum TMW 2.990 was investigated at high pressures (300 to 600 MPa) and ...elevated temperatures (80 to 100 °C) in four low-acid foods (steamed sole, green peas with ham, vegetable soup, braised veal) and imidazole phosphate buffer (IPB). In addition, corresponding conventional thermal treatments at ambient pressure were performed to expose possible synergisms of pressure and temperature on spore inactivation. In general, spore count reduction was more efficient by combining pressure and temperatures < 100 °C and the overall process duration could be shortened due to accelerated heating rates (adiabatic effect). Processing at 90 °C and 600 MPa resulted in inactivation below the detection limit after 5 min in all foods except steamed sole. Traditional thermal processing of spores at 90 °C for 10 min, on the other hand, did not result in an estimated 6-log reduction. Additional HPT treatments in steamed sole and IPB did not reveal pronounced food matrix dependent protective effects. Here, varying pressure levels did not appear to be the driving force for spore count reduction in steamed sole at any temperature. By applying a Weibull distribution on destruction kinetics of isobaric/isothermal holding times, 6D-values were calculated. Compression and decompression phase (1 s pressure holding time) had a considerable impact on spore count reduction (max. -2.9 log units) in both, foods and buffer. Hence, compression and decompression phases should directly be included into the total lethal effect of HPT treatments to avoid prolonged holding times and overprocessing.
During the last decade, pressure intensified technologies have become more attractive and competitive alternatives for several industrial processes. A growing interest in safe and environmentally ...friendly products, the increasing availability of industrial-scale commercial units, and the stricter regulations are the main reasons behind this phenomenon. In particular, supercritical and subcritical fluid technologies offer suitable alternatives for the processing of citrus fruits. On the one hand, these technologies can replace conventional processes all along the production chain, i.e., peel oil refinement, preservation of organoleptic properties of juices, pectin extraction, etc. On the other hand, the selective green solvents used in these technologies allow obtaining high-quality and high-value-added products from citrus fruit waste. In this review, the most significant achievements in the processing of citrus fruits and derived wastes by innovative supercritical and subcritical fluid technologies are presented. Advantages and drawbacks against conventional processes, as well as future perspectives, are discussed.
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•Citrus fruits are among the ten higher global gross production value crops.•Almost half of the production is discarded as low-cost by-products.•Novel pressure intensified technologies for the overall processing of citrus fruits.•Selective green solvents for producing high-quality and high-added-value products.•Pro and cons against conventional industrial processes and future perspectives.
To date, the oxidation behavior of crystal materials is not fully understood; additional research is needed to understand the oxidation of materials. Herein, density functional theory (DFT) ...calculations and a 3D kinetic Monte Carlo (KMC) model are used to investigate the infiltration and diffusion behaviors of oxygen atoms within the crystal. Oxygen molecules readily adsorbes on crystal surfaces of the material and rapidly dissociates, verified by both first-principles calculations and energy-dispersive spectrometer (EDS) results. The infiltration ability of oxygen atoms into the inner crystal layers is affected by the surrounding oxygen atom, lattice compactness, and other factors. Energy-barrier calculations show that crystal thin/dense layers have significant effects on the crystal oxidation process, so high-pressure technology is used to investigate this correlation experimentally. KMC calculations and thermogravimetric analyses (TGA) show the infiltration behavior of oxygen atoms in the main crystal plane (211) toward the inner layers has the highest proportion to the actual high-temperature oxidation behavior of the title material. The results of both the KMC calculations and thermal experiments show the material peeled off upon further oxidation, which accelerates oxidation. At the same time, high-pressure treatment increases the oxidation resistance of materials at lower temperatures (<600 °C).
Blue crab (Callinectes sapidus) is a highly valuable wild fishery species of crab native to the waters of the western Atlantic Ocean and the Gulf of Mexico. The annual commercial production of live ...blue crabs is approximately 50,000 metric tons with a dockside value of USD 200 million. Presently the US blue crab processing industry sells crab meat in three basic forms: fresh crab meat, pasteurized crab meat, and frozen crab meat. By far “Fresh” is the most desirable form of crab meat. However, fresh crab meat has a limited shelf life. This study evaluated the effects of high-pressure processing (HPP) on enhancing the microbiological quality and shelf life of blue crab meat. Live blue crabs were pressure-cooked in a retort (≥115 °C for 4–6 min). The crab meat was handpicked, packed in plastic containers with seals, subjected to HPP treatment, and stored at 4 °C. Container integrity and water leakage issues were examined by observation in addition to weight comparison before and after HPP treatment; the shelf life of crab meat with and without HPP treatments was examined via microbiological tests and sensory evaluations. Results show that polypropylene containers sealed with 10K OTR (oxygen transmission rate) film could withstand high pressure without water leakage issues; HPP treatment at 600 MPa for 3 min could extend the shelf life of fresh, cooked, and handpicked crab meat from 6 days to 18 days based on the strictest APC (aerobic plate account) limit (APC ≤ 100,000 CFU/g). The sensory quality of the HPP-treated crab meat was well accepted throughout the 3-week storage period. The results support the use of HPP as an effective non-thermal processing technology to enhance the microbiological quality and extend the shelf life of fresh RTE blue crab meat.
In diesem Beitrag stellt sich Juniorprofessorin Sulamith C. Frerich von der Ruhr‐Universität Bochum (RUB) vor. Sie gibt Einblick in aktuelle Forschungsfragen und zeigt, wie sie universitäre Aufgaben ...mit außeruniversitärer Forschung verbindet. Fachlich berichtet sie aus Kunststoffcharakterisierung und ‐verarbeitung sowie numerischer Simulation und Prozessoptimierung. Für die anwendungsnahe Kompositherstellung aus Polymeren und Wirkstoffen nennt sie zwei Beispiele und beschreibt, wie sie den Transfer gestaltet. Zusätzlich erläutert sie, wie Online‐Lehre in der Verfahrenstechnik funktioniert.
In this article, junior professor Sulamith C. Frerich from the Ruhr University Bochum (RUB) introduces herself. She provides insight into current research issues and shows how she combines university tasks with non‐university research. She reports from plastics characterization and processing as well as numerical simulation and process optimization. She gives two examples for application‐oriented composite production from polymers and active ingredients and describes how she designs the transfer. In addition, she explains how online teaching works in process engineering.
Juniorprofessorin Sulamith C. Frerich von der Ruhr‐Universität Bochum (RUB) gibt Einblick in aktuelle Forschungsfragen im Sinne der Nachhaltigkeit. Ihre Schwerpunkte liegen in der Verarbeitung und Charakterisierung von Kunststoffen in Gegenwart von verdichteten Gasen, wobei sie die Prozesse unter Einsatz numerischer Simulationen optimiert.
The term “chemical reactor” appears for the first time in open literature at the end of First World War, while in Germany the term “reaction technology” was coined in the 1950s, although chemical ...reactions and processes have been known for thousands of years. In the early days, reactors were furnaces and pots, which specialized further over the centuries. With the Industrial Revolution many reactor types were already known, and industrialization brought an enormous innovation thrust in the field of products as well as technologies. The diversity of reactors today is almost uncomprehensive and so efforts to standardize apparatus are understandable.
The reactor technology evolved from simple pots and ovens to modern stirred tank and tubular reactors. Product development, process knowledge, material science and simulation tools guided the development to a high variety. Currently, modular design and planning methods lead to standardized equipment.
The effects of soaking milkfish fillet in 3% or 9% NaCl brines for 90 min at 4°C, and followed by processing with varying hydrostatic pressures (300, 400, 500, and 600 MPa) for 5 min on microbial ...quality and physicochemical properties were evaluated. After brine salting, the color of the fillet, the L* (lightness), W (whiteness), and ΔE (color difference) values increased with the increases in pressure, whereas the a* (redness) and b* (yellowness) values decreased, indicating that the fillet became brighter and whiter. Among them, 3% brine salting combined with pressures of 300 and 400 MPa groups had higher redness (a* value) and lower ΔE value compared to the higher pressure groups. Regarding the texture of the fillet, the hardness and chewiness of unsalted fish were significantly higher than that of brine salted fish under the same pressure, whereas the cohesiveness of the unsalted fillet was significantly lower than that of brine salted fillet. The results indicates that brine salting could make the instrumental texture of fish softer, which can compensate for the disadvantages of increased hardness and chewiness of the fillet caused by high-pressure processing. Brine salting combined with high pressure produced a significantly reducing effect on aerobic plate count (APC), psychrotrophic bacteria count (PBC), and total volatile basic nitrogen (TVBN) values of the fish as compared with that by brine salting or high pressure alone. Therefore, brine salting at a proper brine concentration (3%) and followed by high-pressure processing at 300 or 400 MPa for 5 min can improve or maintain a relatively good color and texture, as well as result in a synergistic bactericidal effect.
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