Search Results (4,486)

Optimal sous-vide and multiphase cooking strategies remain underexplored despite their potential to improve the tenderness and juiciness of chicken breast. This study aimed to optimize sous-vide cooking conditions (Experiment I) and evaluate the effects of stepwise sous-vide cooking on the quality attributes (Experiment II). In Experiment I, a two-factor, three-level central composite design was employed to optimize the temperature (50, 60, and 70 °C) and time (3, 4.5, and 6 h) using response surface methodology. The optimal condition (55 °C for 3 h) significantly reduced cooking loss (11.47%) and shear force (11.84 N). In Experiment II, five cooking conditions were compared: conventional control (75 °C/30 min), sous-vide control (55 °C/180 min), and three stepwise methods (Stepwise I, 45 °C/180 min + 55 °C/180 min; Stepwise II, 55 °C/180 min + 75 °C/8.5 min; and Stepwise III, 55 °C/180 min + 95 °C/3 min). Stepwise II and III increased cooking loss (16.4% and 20.5%, respectively) and reduced moisture (p < 0.05), but Stepwise II significantly decreased shear force (12.50 N), retaining moisture comparable to conventional control (17.35 N). Stepwise sous-vide cooking, particularly Stepwise II, appears promising for enhancing tenderness without causing excessive water loss. Further research should evaluate the sensory properties and microbiological safety for potential practical applications. Full article

The microencapsulation of bioactive compounds from rapeseed oil using sodium alginate, in the presence and absence of an ultrasonic (US) field, is reported. A Box–Behnken experimental design is used to investigate the influence of process parameters on the microencapsulation yield; then, the response surface methodology is applied, to find their values ensuring its optimum yield. The operating parameters investigated are the ratio of sodium alginate to rapeseed oil, the microencapsulation time and the concentration of the calcium chloride solution. The US bath was used at its nominal power, and the microencapsulation temperature was kept at 20 °C, with a thermostat, for all experiments. A detailed study on the comparison of the two microencapsulation techniques (in the presence and absence of the US field) was carried out. Good results were obtained in the presence of the US field for optimal conditions, when the microencapsulation yield was 90.25 ± 0.02%, higher than the microencapsulation process performed in the absence of the US field, 87.11 ± 0.02%. The results also showed that the use of the US field (optimal conditions) led to an increase in encapsulation efficiency, total phenolic content and antioxidant capacity (76.56 ± 0.02%, 324.85 ± 0.01 mg GAE/g and 57.05 ± 0.12 mg/mL). The physicochemical description of microcapsules was performed using modern characterization methods. These results indicate that by increasing the microencapsulation yield of bioactive compounds through sonication, the process aims to achieve a uniform size distribution of microcapsules. Full article

This study evaluates the effects of steel slag powder (SSP), fly ash (FA), and steel slag sand (SSS) on mortar compressive strength. A response surface methodology (RSM) based on central composite design (CCD) was employed to model 7-day, 28-day, and 91-day strength development, considering three quantitative variables: SSP, FA, and SSS. Statistical results confirmed the reduced cubic models were significant and predictive (R² > 0.97), with non-significant lack of fit and adequate precision. Experimental results revealed that SSP and FA negatively affected early-age strength due to dilution effects and low initial reactivity, whereas SSS slightly improved it by enhancing particle packing. At later ages, SSP exhibited nonlinear effects, where moderate dosages enhanced strength, while excessive replacement led to strength reduction. SSS showed a continuously positive contribution across all ages, particularly at 91 days. Perturbation plots, contour maps, and gradient analyses indicated that SSS played a dominant role at later stages and that maintaining a proper balance among supplementary cementitious materials (SCMs) and aggregate replacements is crucial. The developed models and response surfaces provide practical guidance for designing slag-based mortars with improved mechanical properties and enhanced sustainability. Full article

Robust strains with high simultaneous nitrification and denitrification (SND) capabilities in hypersaline wastewater, particularly those containing different oxysalts, are rarely reported. Here, an isolated oxysalt-tolerant bacterium, Marinobacter sp. Y2, showed excellent nitrogen removal capabilities of around 98% at 11% salinity of NaCl or oxysalts such as Na₂SO₄, Na₂HPO₄, NaHCO₃, and NaNO₃ through response surface methodology optimization. At >5% salinities, Marinobacter sp. Y2 showed superior nitrogen removal performance in oxysalt-laden wastewater compared to chloride-based wastewater. In contrast, other SND strains, including Pseudomonas sp. and Halomonas sp., experienced significant activity inhibition and even bacterial demise in oxysalt-rich wastewater, despite their high halotolerance to NaCl. The excellent SND activities of the oxysalt-tolerant strain were further validated using single and mixed nitrogen sources at 11% Na₂SO₄ salinity. Moreover, the amplification of nitrogen removal functional genes and the corresponding enzyme activities elucidated the nitrogen metabolism pathway of the strain in harsh oxysalt environments. Full article

Ultrasound (US) is a non-thermal food processing method that can be used as a pre-treatment or integrated during drying to enhance mass transfer by inducing cavitation and forming microchannels in plant tissue. Thus, this study investigated the combined effect of ultrasound pre-treatment (21 kHz; 180 W; 10 min, 20 min, 30 min) and the subsequent hybrid drying process—ultrasound-assisted hot-air drying (temperature of 70 °C, frequency of 36 kHz; ultrasound power of 120 W, 160 W, 200 W)—on the drying kinetics and quality attributes of dried Gloster apples. The experimental design was optimized using the response surface methodology (RSM). The effects of ultrasound parameters on drying time, dry matter content, water activity, rehydration and hygroscopic properties, color change, textural properties, content of vitamin C, polyphenols and flavonoids, and antioxidant activity were evaluated. Among the analyzed variants, the most effective combinations were longer US duration (30 min) with lower US power (120 W) or shorter US duration (10 min) with higher US power (200 W). To obtain dried material with the most desirable rehydration and hygroscopic properties, a US power in the range of 120–160 W, preceded by a US pre-treatment lasting 20 min, should be selected. Conversely, optimizing the content of bioactive components would involve choosing the longest US treatment time and medium to high ultrasonic power during drying. These results provide actionable insights for the industry to tailor drying parameters based on the desired product attributes. Full article

This study compares the phenolic composition and antioxidant activity of extracts obtained using heat-assisted extraction (HAE) and ultrasound-assisted extraction (UAE), both optimized through response surface methodology (RSM), with the primary goal of maximizing the extraction of bioactive compounds from Thymus vulgaris L. Eight phenolic compounds were identified in the extracts, with rosmarinic acid being the most abundant. Depending on the selected conditions in each optimization, the concentration of this compound varied from 2.04 to 72.6 mg/g of extract for HAE and 0.73 to 73.5 mg/g of extract for UAE. The optimal conditions for each method that yielded the highest rosmarinic acid levels were as follows: for HAE, 27% ethanol at 91 °C for 121 min; and for UAE, 60 min at 500 W using 50% ethanol. The UAE-produced extract demonstrated superior antioxidant performance, particularly in inhibiting the formation of thiobarbituric acid reactive substances and oxidative haemolysis. Additionally, the extracts obtained using both optimized methodologies exhibited cytotoxic activity against five tumor cell lines and showed significant bactericidal and fungicidal effects against six bacterial and fungal strains. Overall, UAE proved more efficient as it enables the production of rosmarinic-acid-enriched extracts in less time, making them suitable as natural ingredients for industrial applications. Full article

This study presents a systematic calibration of discrete element model (DEM) parameters for fermented grains (19.4% moisture) using the Hertz–Mindlin with JKR contact model to optimize robotic end-effector design in liquor distillation. By integrating cylinder lift experiments and response surface methodology, we identified three critical parameters (JKR surface energy, restitution, and rolling friction coefficients) through Plackett–Burman screening and steepest ascent optimization. The Box–Behnken design derived optimal values of 0.0429 J/m² surface energy, 0.183 restitution coefficient, and 0.216 rolling friction coefficient. The validation results demonstrated excellent agreement between the simulated and experimental angles of repose (AORs), with a simulated AOR of 36.805° and an experimental value of 36.412°, corresponding to a 1.08% error. The geometric congruence of the deposition morphology and the notable symmetrical distribution characteristics of the left and right angles of repose confirm the robustness of the parameter calibration methodology. This study provides a theoretical basis for the kinematic parameter optimization of the end-effector distribution mechanism in fermented grain-loading robots, providing critical insights for advancing automated control in solid-state liquor distillation processes. Full article

The response surface methodology (RSM) is utilized to construct a corrosion prediction model for steel pipelines for underground gas storage (UGS). Four key corrosion-influencing factors—the CO₂ partial pressure, Cl⁻ concentration, temperature, and flow rate—are identified by investigating the operating parameters of 14 UGS extracted pipelines (Nos. S1–S14) in China. Based on the operating parameters, 29 sets of high-temperature and high-pressure autoclave corrosion tests are designed and carried out. A quadratic regression equation model for corrosion rate prediction is fitted using the data from the corrosion test results. The p-values of the model’s four influencing factors are <0.01, indicating that the influencing factors are significant and reasonable. The F-value of the model is greater than the critical value, and the noise probability p-value is <0.01, indicating that the model has good fitness. The determination coefficient R² of the model is 0.9753, which is close to 1. Therefore, the observed value and the response value of the model are obviously correlated: i.e., the model has a high degree of truth. The model is used to predict the corrosion rate of 14 UGS pipelines: S3 and S14 are severely corroded, while the others are moderately corroded. Full article

Microbially synthesized postbiotics have unique properties and advantages; however, systematic studies on the efficient production and biological functions of postbiotics from Bacillus subtilis are limited, which greatly restricts their applications. In this study, we obtained a novel crude exopolysaccharide (EPS) postbiotic from Bacillus subtilis H4. We systematically optimized the EPS production strategy using single-factor analysis, Plackett–Burman design, the path of steepest ascent method, and response surface methodology. The optimized EPS yield was significantly improved, with a maximum yield of 15.01 g/L under the addition of 4.12% soy peptone, 8.99% sucrose, and 0.06% MnSO₄. We found that EPS is a neutral, heterogeneous polysaccharide with a pyranose ring, with a molecular weight of 44,304.913 kDa and a melting point of 218 °C. It consists of glucose, galactose, arabinose, glucosamine, and mannose at a molar ratio of 58.85:19.81:14.75:10.89:6.58. EPS exhibits strong antioxidant capacities, scavenging ABTS and DPPH radicals with IC50 values of 1 and 6 mg/mL, respectively. Moreover, it shows notable anti-inflammatory properties, dramatically inhibiting the lipopolysaccharide (LPS)-induced elevation of nitric oxide (NO) levels and over-activation of the TLR4-NF-κB signaling pathway. These findings highlight the potential of EPS as a multifunctional bioactive compound, offering great promise for its application in the food, clinical, and feed industries. Full article

Marine biofouling is a significant challenge for industries that rely on seawater. This study examined the effect of structural materials, carbon concentration, and salinity on biofilm formation. Furthermore, it compares the disinfection efficiency of chlorine (NaClO) and bromine (NaBr) biocides and attempts to identify their optimal dosing. Among tested materials, PVC exhibited the highest microbial attachment (40%), followed by plastic (30%) and concrete (23%). Biofilm attachment and growth increased with higher concentrations of total organic carbon (TOC), which depends upon the seawater’s salinity. The simultaneous reduction of salinity and TOC concentration further enhanced the biofilm attachment and growth. A strong positive linear correlation (r = 0.98 and p = 0.003) was found between the initial cell count of seawater and biofilm formation. Disinfection experiments showed that NaBr (97.36%) was slightly more effective than NaClO (95.83%). Response Surface Methodology (RSM) identified optimal disinfection conditions: 0.6 mg/L biocide concentration and 138 min dosing period. Generally, there are three strategies for reducing biofilm growth: selecting appropriate materials, controlling carbon concentrations, or optimizing concentrations and dosing periods with biocides. Full article

Ferritin, an emerging protein resource, has garnered significant attention in scientific research due to its biocompatibility and unique cavity structure capable of encapsulating bioactive compounds. This study aimed to optimize ultrasound-assisted extraction (UAE) for enhancing ferritin yield from northern pike liver byproducts and evaluate its potential as a nanocarrier for chlorogenic acid (CA). Through response surface methodology (RSM), the optimal UAE parameters were established as 200 W ultrasonic power, 1:3 solid–liquid ratio, and 25 min extraction time. Under these conditions, the ferritin extraction yield reached 139.46 mg/kg, representing a 4.02-fold increase compared to conventional methods (34.65 mg/mL). Electrophoretic analysis confirmed the electrophoretic purity of the extracted liver ferritin. Comprehensive characterization using UV-vis spectroscopy, FTIR, and fluorescence spectroscopy revealed preserved structural integrity of UAE-extracted ferritin. Homology modeling provided molecular insights into the ferritin architecture. Successful encapsulation of CA was achieved with an encapsulation efficiency of 13.25%, as quantified by HPLC. Analysis by DLS and ζ potential as well as TG and DSC showed that not only the thermal stability of CA was enhanced after ferritin encapsulation, but also that the ferritin remained stable with a cage-like structure. This investigation establishes UAE as an effective strategy for valorizing fish processing byproducts through high-yield ferritin extraction while demonstrating the protein’s functional capacity as a nanocarrier for bioactive compound delivery. The findings highlight the dual advantage of sustainable resource utilization and advanced delivery system development through this biotechnological approach. Full article

In this study, C18-functionalized magnetic silica nanoparticles (Fe₃O₄@SiO₂@C18) were used as adsorbents for the magnetic solid-phase extraction (MSPE) of organic contaminants commonly applied to aquaculture water (organic booster biocides, herbicides, and insecticides) followed by Gas Chromatography coupled to Mass Spectrometry (GC–MS). The extraction conditions and efficiency of the nanoparticles for the determination of ten pesticides (atrazine, ethoxyquine, chlorothalonil, chlorpyriphos methyl, methyl parathion, chlorpyriphos, resmethrin, λ-cyhalothrin, permethrin, and irgarol) were thoroughly investigated. Several experimental parameters affecting the extraction efficiency such as the amount of sorbent, extraction time, and elution time were optimized by employing experimental designs as response surface methodology. Validation experiments showed that the average recoveries of target analytes were in the range of 60% to 99%. The optimized method exhibited good linearity (R² > 0.9901) and satisfactory precision (Relative Standard deviations, RSDs < 15%). The method detection limits ranged between 1.9 ng L⁻¹ and 62 ng L⁻¹. Finally, the MSPE method was successfully applied to aquaculture water samples collected from the Thesprotia region (N.W. Greece), Thermaikos Gulf (N. Greece) and Butrint (S.W. Albania). Full article

β-glucans from filamentous fungi are important for human health. There is limited research on polysaccharides from filamentous fungi, and no reports have been published regarding the optimization of culture media to produce β-glucans from Rhizopus oryzae using liquid waste from potato starch processing. In this regard, the fermentation conditions to produce β-glucans from Rhizopus oryzae M10A1 were optimized using the one variable at a time (OVAT) and response surface methodology (RSM). The β-glucans were chemically characterized by determining moisture, nitrogen, protein, fat, ash, and total carbohydrates. The color, molecular weight, β-glucan content, monosaccharide composition, and structural and conformational characteristics were assessed by colorimetry, gel permeation chromatography, high-performance liquid chromatography, and Fourier transform infrared spectroscopy, respectively. The microbial indicators, mesophilic aerobes, molds, yeasts, and Escherichia coli were quantified following ISO standard protocols. Optimization indicated that supplementation with 0.8% (w/v) glucose and ammonium sulfate enhanced heteroglycan production (3254.56 mg/100 g of biomass). The β-glucans exhibited high purity, a light brown color, a molecular weight of 450 kDa, and a composition predominantly consisting of glucose and galactose. These findings suggest that β-glucans from Rhizopus oryzae M10A1 could be used for food and health applications. Full article

Understanding cancer etiology requires replicating the tumor microenvironment (TME), which significantly differs from standard in vitro cultures due to nutrient limitations, acidic pH, and oxidative stress. To address this, a microfluidic bioreactor (µBR) with an expanded culture surface was designed to optimize exosome enrichment and glioblastoma cell behavior. Using response surface methodology (RSM), key parameters—including medium exchange volume and interval time—were optimized, leading to about a six-fold increase in exosome concentration without artificial inducers. Characterization techniques (SEM, AFM, DLS, RT-qPCR, and ELISA) confirmed significant alterations in exosome profiles, cancer stemness, and epithelial-mesenchymal transition (EMT)-related markers. Notably, EMT was induced in the µBR system, with a six-fold increase in HIF-1α protein despite normoxic conditions, suggesting activation of compensatory signaling pathways. Molecular analysis showed upregulation of SOX2, OCT4, and Notch1, with SOX2 protein reaching 28 ng/mL, while it was undetectable in traditional culture. Notch1 concentration tripled in the µBR system, correlating with enhanced stemness and phenotypic heterogeneity. Immunofluorescent microscopy confirmed nuclear SOX2 accumulation and co-expression of SOX2 and HIF-1α in dedifferentiated CSC-like cells, demonstrating tumor heterogeneity. These findings highlight the µBR’s ability to enhance stemness and mimic glioblastoma’s aggressive phenotype, establishing it as a valuable platform for tumor modeling and therapeutic development. Full article

Sunflower press cake (SPC), a by-product of the edible oil industry, represents a promising source of plant-based protein. This study aimed to investigate and optimize protein recovery from SPC using conventional (CE) and advanced extraction techniques, including Ultrasound and Microwave-Assisted Extraction (UMAE), Pressurized Liquid Extraction (PLE) and Enzyme-Assisted Extraction (EAE). The protein content both in extracts and in the precipitated mass was measured through Lowry assay, while the amino acid profile of the extracted proteins under optimal conditions was analyzed via High-Performance Liquid Chromatography (HPLC). Extraction parameters were optimized using response surface methodology (RSM) for each method. Among the novel methods studied, UMAE and PLE demonstrated superior efficiency over CE, yielding higher protein recovery in significantly shorter extraction times. Optimal UMAE conditions (10 min, 0.03 g/mL, 450 W microwave power, and 500 W ultrasound power) yielded a precipitation yield (PY) of 21.2%, protein recovery in extract (PR_E) of 79.9%, and protein recovery in precipitated mass (PR_P) of 66.3%, with a protein content (PC_P) of 902.60 mg albumin eq./g. Similarly, optimal PLE conditions (6 min, 0.03 g/mL, and 50 °C) resulted in PY, PR_E, and PR_P of 17.7, 68.9, and 47.4%, respectively, with a PC_P of 932.45 mg albumin eq./g. EAE using Aspergillus saitoi protease was comparatively less effective. The amino acid profiling confirmed SPC as a valuable protein source, with glutamic acid, arginine, and aspartic acid being the most abundant. These results highlight the potential of UMAE and PLE as efficient strategies for valorizing edible oil industry by-products into high-quality protein ingredients for food and biotechnological applications. Full article