Independent Process Variables Research Articles

Sustainable production of biodiesel from waste cooking oil using magnesium oxide nano catalyst: An optimization study

Biodiesel is rapidly becoming an efficient substitute for fuel and a potentially significant future renewable energy source. In recent years, used cooking oil has been used as a feedstock for biofuel to reduce production costs. Due to its high catalytic activity, low cost, and eco-friendliness, Nano magnesium oxide (MgO) has attracted attention as a catalyst for biodiesel production. Our work presents the preparation of nanomagnesium oxide (MgO) by the sol–gel method, and its characterization. Optimum conditions and the productive combination of waste cooking oil, methanol, and the synthesized nanocatalyst were predicted using response surface methodology. The optimum conditions were methanol to oil ratio of 7:1, temperature of 50 °C and time of 60 min. The expected values for the yield of biodiesel production responses are quite like the actual values, demonstrating the consistency of the models used for establishing a relationship between the independent process variables and the responses. The predicted model's F-value was 9.09 indicating that the model is significant. The model's pure error had a poor correlation, as the "Lack of Fit F-values” 4.16. The quadratic model fits the data well because the R-squared value for the model equation 92%. The expected values for the yield of biodiesel production responses are quite like the actual values, demonstrating the consistency of the models used for establishing a relationship between the independent process variables and the responses. Biodiesel was characterized using gas chromatography–mass spectrometry and Fourier transform infrared spectroscopy.

DESIGN AND IN VIVO EVALUATION OF NAPROXEN-LOADED TRANSFEROSOMAL GEL FOR TRANSDERMAL DELIVERY

Objective: The main objective of the present study was to formulate, optimize, and evaluate naproxen transfersomal gels. Methods: Reverse phase evaporation was used to create thirteen different formulations of naproxen-loaded transfersomes. Using Response Surface Methodology (RSM) and Central Composite Designs (CCD), the influence of independent process variables, such as soy lecithin, cholesterol content and surfactant concentration, on dependent variables, such as entrapment effectiveness and vesicle size of naproxen transfersomes, was assessed. In vitro, ex-vivo, and in vivo drug release of formulations were also studied. Results: It was discovered that the NTG7 formulation of transfersomes had the maximum entrapment effectiveness and ideal vesicle diameter. The optimized NTG7 formulation displayed a maximum drug content of 97.4% and a maximum drug release of 88.03%. The release of naproxen from the final gel adhered to the Korsmeyer-Peppas release model. The ex-vivo drug release of the optimized formulation was found to be 85.91% for 24 h. The maximum drug concentration after oral administration was 843.54±7.67ng/ml, and Tmax was 3.0±0.08h. The improved formulation's AUC0-∞ was greater than the commercial formulation's. A higher drug concentration in the blood compared to the marketed formulation suggested better systemic absorption of naproxen from the gel formulation. After three months, at a temperature range of 2 to 8 °C, the formulation demonstrated correct semisolid consistency and good stability and there was also no appreciable change in the initial values of appearance, pH, and % drug content. Conclusion: The above findings imply that the gel created using naproxen-loaded transfersomes may be a potentially valuable new formulation.

Optimization of Process Variables in the production of Biodiesel from Jatropha-Neem Hybrid Feed stock Mixture

In the search for suitable clean and renewable fuels to replace conventional diesel, alternatives such as biodieselsare being researched upon daily. Challenges of low biodiesel yield per hectare of vegetable oils have prompted the need for optimization. This research is aimed at optimizing process variables in the production of biodiesel from the mixture of Jatropha and Neem seed oils. A 31-run Central Composite Design was employed in a response surface optimization process; four independent process variables, namely temperature, time, catalyst concentration and mixing speed were optimized in an alkali based transesterification process of biodiesel synthesis. The result was a 97.05% biodiesel yield from Jatropha –Neem hybrid mixture.

Methocarbamol Transferosomal Gel For Topical Delivery: In-vitro, Ex-vivo and In-vivo Evaluation

Because of their capacity to permeate across the stratum corneum’s barriers to penetration, transferosomes are one of the vesicular transporters that have recently attracted a lot of research and attention. The current study aimed to analyze and improve methocarbamol transferosomal transdermal gels. Reverse phase evaporation was used to create thirteen different formulations of methocarbamol-loaded transfersomes. Using face-centered central composite designs, the influence of independent process variables, like soy lecithin content and surfactant concentration, on dependent variables, such as entrapment effectiveness and the vesicle size of methocarbamol transfersomes, was assessed. The ex-vivo permeation flux of methocarbamol and the lipid to surfactant ratio/skin absorption efficiency of the drug and transferosomal gels were optimized. The optimized formulation showed an entrapment efficiency of 95%, a vesicle diameter of 428 nm, a drug content of 96.6% and a zeta potential of −28.9 mV. In-vitro and ex-vivo drug release rate in optimised gels was found to be 86.43 and 84.12% for 24 hours, respectively. This tranferosomal delivery method for transdermal methocarbamol may be preferable to the standard of care.

Removal of Dibenzothiophene from Liquid Fuels by Photocatalytic Desulfurization over Zn‐Terephthalate Complex: A Process Modelling and Optimization by Response Surface Methodology

AbstractThe Zn‐terephthalate complex was synthesized by hydrothermal method at 180 °C and applied as a novel macroporous photocatalyst in the desulfurization of dibenzothiophene (DBT) from a fuel model to produce DBT sulfone. The physical‐chemical properties of the photocatalyst were characterized by Fourier Transform Infrared (TIR), Raman spectroscopy, powder X‐ray diffraction (XRD), field‐emission scanning electron microscopy (FESEM), photoluminescence spectroscopy and UV‐Vis diffuse reflectance spectroscopy (UV‐Vis DRS). The characterization results indicated the formation of mono‐nuclear paddlewheel metal‐organic framework (MOF) as Zn [COO]2 frameworks. The photocatalytic experiments were designed by the Box‐Behnken method of response surface methodology (RSM) and the photocatalytic process was modelled and optimized. Three independent process variables i. e. concentration of dibenzothiophene, the amount of photocatalyst and light irradiation time were considered in the experimental design. The determination coefficient (R2) of the model is 0.97. The optimum removal of DBT (50.4 %) resulted in a fuel model containing 50 ppm DBT, desulfurized by 0.060 g of Zn‐MOF photocatalyst under visible light for 180 min. The predicted response (DBT removal%) by the RSM model was 50.68 %. According to the Pareto analysis, the order of importance of independent factors on the response was as follows: Irradiation time>m(photocatalyst)>C(DBT).

Assessing and optimizing the efficacy of synthesized CaO-based nano-catalysts for biodiesel production

ABSTRACT The current research proposed the work on the consumption of waste cooking oil (WCO) as a valuable resource for the production of biodiesel. This study focuses on maximizing output yield by employing composite heterogeneous catalysts, namely calcinated calcium oxide with aluminum oxide (CaO/Al2O3) and calcium oxide with titanium oxide (CaO/TiO2). The calcination process was adopted for the catalysts at 600°C for 5 h to improve catalytic activities and to increase surface area. XRD and TGA were implemented to analyze the crystal structure and thermal stability of these heterogeneous catalysts. Experimentation was planned by implementing the response surface methodology (RSM) approach in combination with the Box-Behnken design. The optimum yield of fatty acid methyl esters (FAMEs) was experimentally observed at 96.56%, using CaO/Al2O3 at methanol to oil (m/o) molar ratio of 11.9:1, 3.19% catalyst loading, 53.79°C and 76.86 minutes (min). The maximum experimental yield with CaO/TiO2 was observed at 98.15% with the optimized operating conditions of independent process variables viz. m/o molar ratio 11:99, 2.53 wt.% catalyst loading and 68.14 min at 59.79°C. The research recommends the potential use of WCO and both the heterogeneous catalysts for optimal biodiesel yield; however, CaO/TiO2 exhibits superior performance over CaO/Al2O3, which is also confirmed by the XRD and TGA results.

Application of Response Surface Methodology to Improve the Tableting Properties of Poorly Compactable and High-Drug-Loading Canagliflozin Using Nano-Sized Colloidal Silica.

Designing a robust direct compression (DC) formulation for an active pharmaceutical ingredient (API) with poor flow and compaction properties at a high API load is challenging. This study tackled two challenges: the unfavorable flow characteristics and tableting problems associated with a high-drug-loading canagliflozin (CNG), facilitating high-speed DC tableting. This was accomplished through a single-step dry coating process using hydrophilic nano-sized colloidal silica. A 32 full-factorial experimental design was carried out to optimize the independent process variables, namely, the weight percent of silica nanoparticles (X1) and mixing time (X2). Flow, bulk density, and compaction properties of CNG-silica blends were investigated, and the optimized blend was subsequently compressed into tablets using the DC technique. A regression analysis exhibited a significant (p ≤ 0.05) influence of both X1 and X2 on the characteristics of CNG with a predominant effect of X1. Additionally, robust tablets were produced from the processed powders in comparison with those from the control batch. Furthermore, the produced tablets showed significantly lower tablet ejection forces than those from the control batch, highlighting the lubrication impact of the silica nanoparticles. Interestingly, these tablets displayed improved disintegration time and dissolution rates. In conclusion, a dry coating process using silica nanoparticles presents a chance to address the poor flow and tableting problems of CNG, while minimizing the need for excessive excipients, which is crucial for the effective development of a small-sized tablet and the achievement of a cost-effective manufacturing process.

Optimization of osmotic dehydration of orange pieces (valencia late) in sugar solution using response surface methodology

Response surface methodology was used to determine the optimum processing conditions that yield maximum water loss and weight reduction and minimum solid gain during osmotic dehydration orange pieces (valencia late) in sugar solution using response surface. The experiments were conducted according to a Central Composite Design ‘CCD’. The independent process variables for osmotic dehydration process were temperature (40, 50, 60 °C), processing time (60, 120 et 240 min) and sugar concentrations (45, 55, 65 % w/w). The optimal conditions for maximum water loss, weight reduction and solid gain (candying) correspond to temperature of 50 °C, processing time of 240 min, sugar concentration of 65 % in order to obtain water loss 60.83 % (g/100 g fresh sample), solid gain of 46,48 % (g/100 g fresh sample) and weight reduction of 57.42 (g/100 g fresh sample). However the optimal conditions for maximum water loss and weight reduction and minimum solid gain (respectively 53.28 %, 57.88 % and 27.18 %) correspond to temperature of 40 oC, processing time of 240 min, sugar concentration of 65 %.

Maize cob-derived activated carbon as an adsorbent for the removal of nickel (II) cation from aqueous solution: optimization and kinetic studies

Adsorption performance of maize cob-derived activated carbon (MCAC) for the removal of nickel (II) from solution was investigated in the present study. The MCAC was prepared by adsorbent chemical activation method. Afterwards, the MCAC was characterized and utilized as the adsorbent for batch adsorption process. Initial adsorbate concentration, contact time and adsorbent dosage were considered as the independent variables for the adsorption process. The experiments were designed based upon central composite design (CCD) of response surface methodology with the aid of Design Expert. The experimental data were fitted into a model using MATLAB regression analysis, and the developed model was later simulated to obtain the operation parameters that will give the optimum removal efficiency. The analysis of variance (ANOVA) revealed that all the considered independent process variables had significant effect on the adsorption process. The simulated response from MATLAB gave 97.113% removal efficiency of nickel (II) on experimental validation at optimum conditions of 9.75 mg/L initial nickel (II) concentration, 120 min contact time and 0.803 g adsorbent dosage. This result correlates with CCD that predicted 97.6154% nickel (II) removal efficiency. The experimental data were observed to be best fitted to pseudo-second-order kinetic model which showed that the process is chemisorption controlled. Hence, it may be concluded from the present data that MCAC is highly effective for the removal of Ni(II) from aqueous solution and the highly generated agricultural waste (Maize cob) can the easily modified as a adsorbent.

Thermostable keratinase from Bacillus cereus L10: optimization and some potential biotechnological applications

AbstractThe accumulation of feather waste is a critical problem in solid waste management; therefore, microbial management of waste is highly significant. Consequently, the keratinolytic capacity of some bacteria isolated from the keratinous waste area was evaluated. The most promising isolate coded as L10 showed the highest feather degradation efficiency 72.7% was identified as Bacillus cereus L10 using 16S rRNA gene sequencing. The effect and contribution of independent process variables were studied by Plackett–Burman design. The optimal values of the independent variables obtained from the Plackett–Burman design were chicken feather, 1%; K2HPO4, 0.3%; KH2PO4, 0.05%; MgSO4 7H2O, 0.01%; yeast extract, 0.05%; inoculum size 4% with pH 7 and incubation period 5 days at 35 °C. The optimal parameters were validated resulting in the enhancement of keratinase production (9.602 U/ml), protein concentration (521.17 µg/ml), and feather degradation (94%) along with a 4.56-fold increased of keratinase production. The enzyme is relatively thermostable, completely stable between 30 and 80 °C for 1 h and retained 97.66% of its activity at 100 °C. B. cereus L10 was able to degrade different types of keratins. Interestingly, the feather hydrolysate from optimized keratinase production medium showed plant growth promoting activity by producing indole-3-acetic acid (IAA). The feathers hydrolysate produced a great benefit by its use as a soil biofertilizer through enhancing the germination of Triticum aestivum. The important implication of keratinase in laundry detergent and leather industry was examined. Results revealed that the enzyme achieved great efficiency in removing protein and blood-rich stains within 30 min at 36 °C in addition to its thoroughly dehairing of cow-hide after 40 h incubation without any damage. The dehaired pelt exhibited a smooth, velvety, and white color surface, good flexibility. Therefore, our study presents an effective method to turn waste into wealth. Graphical Abstract

Optimization of Mucilage Removal from Cress Seeds (L. sativum)

In this study, optimum removal conditions of the cress seed mucilage by a chemical method were deter-mined. Moreover, proximate analysis (moisture, fat, protein, ash and total carbohydrate) of the cress seed was carried out. The independent process variables were sodium bicarbonate concentration (0-0.5 M), solvent-to-seeds ratio (25-75 ml/g) and soaking time (3-9 hours). A central composite design having 24 points for given independent variables was used and the optimization of the process conditions was done by desirability function approach. The results showed that proximate analysis results of the cress seed were in accordance with the previous reports in literature, and fat and protein percentage was found to be higher than 20%. The mucilage removal study results showed that higher concentrations of sodium bicar-bonate enhanced the mucilage removal. Also, higher soaking times increased the solubility of the seed coat polysaccharides of the cress seeds, resulting in better mucilage removal. The optimum chemical mucilage removal conditions were determined as 0.43 M sodium bicarbonate, solvent-to-seeds ratio of 75 ml/g and 8.96 hours of soaking time. At these conditions, total carbohydrate (determined using Anthrone method) in the final extract was predicted as 2.47 g/ml. Verification tests were carried out at the optimum conditions and there was no statistical difference between experimental (2.64±0.43 mg/ml) and predicted values.

Adsorption of methylene blue dye onto modified activated carbon produced from groundnut shells

In this research work, groundnut shells agricultural byproducts were utilized for the production of modified groundnut shell based activated carbon (MGSAC) through the use of phosphoric acid and ethylene-diamine tetraacetic acid disodium salt (Na2EDTA) as an activating agent and a modifier, respectively. A three factor, two-level full factorial design (FFD) was employed for the exploratory design of experiments (DoE). The independent process variables are temperature, activation time, and activating agent concentration for the production of MGSAC in a muffle furnace. The product yield and methylene blue (MB) dye adsorption were considered as the performance indicators for the process. Regression analysis was conducted to examine the influence of process variables on the responses of the process parameters. From the analysis, it was found that the activation temperature has the most significant effects on the MGSAC product yield and the activation time for the adsorption of MB dye. The results obtained showed that the best operating conditions for production of MGSAC were carbonization temperature of 450°C, activation time of 30 min and activating agent concentration of (35 mmol Na2EDTA; 50% H3PO4) which resulted in the product yield of 55.5% MGSAC, and 99.6% MB dye adsorption. It was also observed that experimental values obtained were in good agreement with the values predicted by the model. Hence, the two-level FFD DoE technique demonstrated worthwhile features in disclosing the dominant factors that affect the production of modified groundnut shell based activated carbon. The products appear to be promising adsorbents for the adsorption of cationic MB dye from wastewaters.

Artificial Intelligence Techniques and Response Surface Methodology for the Optimization of Methyl Ester Sulfonate Synthesis from Used Cooking Oil by Sulfonation.

Herein, the impacts of sulfonation temperature (100-120 °C), sulfonation time (3-5 h), and NaHSO3/methyl ester (ME) molar ratio (1:1-1.5:1 mol/mol) on methyl ester sulfonate (MES) yield were studied. For the first time, MES synthesis via the sulfonation process was modeled using the adaptive neuro-fuzzy inference system (ANFIS), artificial neural network (ANN), and response surface methodology (RSM). Moreover, particle swarm optimization (PSO) and RSM methods were used to improve the independent process variables that affect the sulfonation process. The RSM model (coefficient of determination (R2) = 0.9695, mean square error (MSE) = 2.7094, and average absolute deviation (AAD) = 2.9508%) was the least efficient in accurately predicting MES yield, whereas the ANFIS model (R2 = 0.9886, MSE = 1.0138, and AAD = 0.9058%) was superior to the ANN model (R2 = 0.9750, MSE = 2.6282, and AAD = 1.7184%). The results of process optimization using the developed models revealed that PSO outperformed RSM. The ANFIS model coupled with PSO (ANFIS-PSO) achieved the best combination of sulfonation process factors (96.84 °C temperature, 2.68 h time, and 0.92:1 mol/mol NaHSO3/ME molar ratio) that resulted in the maximum MES yield of 74.82%. Analysis of MES synthesized under optimum conditions using FTIR, 1H NMR, and surface tension determination showed that MES could be prepared from used cooking oil.

Optimization of batch study parameters for the adsorption of lead(II) ions onto spent tea grains

Abstract The present study aims to investigate the use of response surface methodology (RSM) modelling and experimental investigation for the optimization of lead(II) adsorption onto spent tea grains (STG). Independent process variables were optimized and found to be in the range of 38.75 mg/l (initial concentration), 5.20655 (pH), 119.32 rpm (stirring speed), and 3.25 g/l (STG dose) for a contact time of 135.05 min. The optimum adsorption capacity was found to be 8.9087 mg/g through RSM modelling with a maximum of 18.146 mg/g. The batch study was performed by varying different parameters: pH (2.0–7.0), initial concentration (5–50 mg/l), dose (0.1–1 g/100 ml), contact time (15–180 min), and stirring speed (30–200 rpm). The characterization STG was done by proximate and ultimate analysis, FTIR spectroscopy, XRD analysis, thermogravimetric analysis (TGA), and SEM-EDX. By fitting equilibrium data onto Langmuir isotherm model, the maximum adsorption capacity was found to be 24.272 mg/g. The optimum pH found for lead(II) adsorption onto STG was 5. At optimum conditions, the maximum removal efficiency of STG for lead(II) ions’ adsorption is 94.33%. Based on the findings it is safe to conclude that the STG could be used as a potential adsorbent.

EXTRACTION OF BIOACTIVE COMPOUNDS FROM FENUGREEK LEAVES BY MACERATION WITH D-OPTIMAL DESIGN

In this study, optimum extraction conditions of bioactive compounds from fenugreek leaves (Trigonella-foenum graecum L.) were investigated using response surface methodology and the extracts having the highest total phenolic content, total flavonoid compounds, antioxidant activity and total saponin content were achieved. The independent process variables were solvent mixture ratio (water and ethanol, 0-100%), temperature (25-65°C) and sample–solvent ratio (10-50 g/L), and a constant extraction time of 120 minutes was used for all the design points. The experimental study was arranged according to D-optimal combined design and the process conditions were optimized using desirability function approach. Results showed that the extraction of phenolic compounds and antioxidant activity were increased at increasing water ratios and temperature and decreasing sample-solvent ratio. Saponins were extracted better when 25% ethanol was used as solvent. The optimum extraction conditions were determined as 100% of water, 49.71°C of temperature, and 10 g/L of sample–solvent ratio.

Intensification of thorium biosorption onto protonated orange peel using the response surface methodology

Abstract In this research work, intensifying the possibility of protonated orange peel to uptake thorium (IV) ions from aqueous solutions in a batch system was investigated and optimized using the response surface methodology. The effect of three independent process variables including thorium initial concentration, pH, and biosorbent dosage was assessed based on the central composite design. The validity of the quadratic model was verified by the coefficient of determination. The optimization results showed that the rate of thorium (IV) uptake under optimal conditions is 183.95 mg/g. The modeling results showed that the experimental data of thorium biosorption kinetics are fitted well by the pseudo-second-order model. According to the results, the biosorption process reached equilibrium after around 4 h of contact. The Langmuir isotherm describes the experimental biosorption equilibrium data well. The maximum absorption capacity of protonated orange peel for thorium adsorption was estimated by the Langmuir isotherm at 236.97 mg/g. Thermodynamic studies show that thorium adsorption on protonated orange peel is thermodynamically feasible, spontaneous, and endothermic.

In Silico Guided Nanoformulation Strategy for Circumvention of Candida albicans Biofilm for Effective Therapy of Candidal Vulvovaginitis.

Candidal vulvovaginitis involving multispecies of Candida and epithelium-bound biofilm poses a drug-resistant pharmacotherapeutic challenge. The present study aims for a disease-specific predominant causative organism resolution for the development of a tailored vaginal drug delivery system. The proposed work fabricates a luliconazole-loaded nanostructured lipid carrier-based transvaginal gel for combating Candida albicans biofilm and disease amelioration. The interaction and binding affinity of luliconazole against the proteins of C. albicans and biofilm were assessed using in silico tools. A systematic QbD analysis was followed to prepare the proposed nanogel using a modified melt emulsification-ultrasonication-gelling method. The DoE optimization was logically implemented to ascertain the effect of independent process variables (excipients concentration; sonication time) on dependent formulation responses (particle size; polydispersity index; entrapment efficiency). The optimized formulation was characterized for final product suitability. The surface morphology and dimensions were spherical and ≤300 nm, respectively. The flow behavior of an optimized nanogel (semisolid) was non-Newtonian similar to marketed preparation. The texture pattern of a nanogel was firm, consistent, and cohesive. The release kinetic model followed was Higuchi (nanogel) with a % cumulative drug release of 83.97 ± 0.69% in 48 h. The % cumulative drug permeated across a goat vaginal membrane was found to be 53.148 ± 0.62% in 8 h. The skin-safety profile was examined using a vaginal irritation model (in vivo) and histological assessments. The drug and proposed formulation(s) were checked against the pathogenic strains of C. albicans (vaginal clinical isolates) and in vitro established biofilms. The visualization of biofilms was done under a fluorescence microscope revealing mature, inhibited, and eradicated biofilm structures.

Optimization of laccase enzyme extraction from spent mushroom waste of Pleurotus florida through ANN-PSO modeling: An ecofriendly and economical approach

The cardinal focus of this study is to optimize the best reaction conditions for maximizing laccase activity from spent mushroom waste (SMW) of Pleurotus florida. Optimization process parameters were studied by the modeling techniques, artificial neural networking (ANN) embedded in particle swarm optimization (PSO), and response surface model (RSM). The best topology of ANN-PSO architecture was obtained on 4-10-1. The R2, IOA, MSE, and MAE values of the ANN model were obtained as 0.98785, 0.9939, 0.0023, and 0.0251 while, that of the RSM model were obtained as 0.74290, 0.9210, 0.0244, and 0.1110 respectively. The higher values of R2, IOA, and lower values of MSE and MAE of the ANN-PSO model depict that ANN-PSO outperformed compared to RSM and also verified the effectiveness of the ANN-PSO model. The ANN-PSO model performance demonstrates the robustness of the technique in optimizing laccase activity in SMW of P. florida. The optimization results revealed that pH 4.5, time 3 h, solid: solution ratio 1:5, and ABTS concentration of 1 mM was optimal for achieving maximum laccase activity at temperature 30 °C. The enzymatic activity of crude laccase enzyme was obtained as 1.185 U ml−1 without loss of enzyme activity. Additionally, crude laccase enzyme was 1.74 fold partially purified, and 83.54% of the enzyme was yielded. Out of all the independent process variables, ABTS and pH had an influence on laccase activity. Therefore, we anticipate that the findings of this investigation will reduce the ambiguity in maximizing laccase activity and ease the screening process. This study also highlights the comparative cost evaluation of crude laccase enzyme extracted from P. florida and commercial enzymes. There is a great potential for the utilization of the laccase enzyme extracted from SMW and using it for the degradation of recalcitrant micropollutants. Thus, SMW promises a cost-effective and sustainable approach leading towards circular economy.

Second generation extruded snacks from sweet chestnut and corn blends – numerical optimization, nutritional, nutraceutical and storage stability characteristics

Purpose This study aims to develop sweet chestnut incorporated corn-based extrudates by the optimization of process conditions. Design/methodology/approach The independent process variables for extrusion (blend ratio, barrel temperature, screw speed and feed moisture) were investigated to govern their impact on reliant variables, namely, bulk density, specific mechanical energy, water absorption index, water solubility index, color and hardness. Product and system responses were significantly (p < 0.05) affected by the independent variables. Experimental design with quadratic models experienced a high coefficient of determination (R2 = 0.99). Findings Numerical optimization for the development of extrudates resulted in optimum conditions having corn flour: sweet chestnut flour (80:20), barrel temperature (120°C), screw speed (340 rpm) and feed moisture (12%). Fat, moisture and protein contents of the developed extrudates using optimum conditions were significantly (p < 0.05) lower compared to raw materials – corn and sweet chestnut. The packaging of extrudates in aluminum laminates revealed shelf stability of three months at room temperature without deterioration of quality. Originality/value Nutritionally rich sweet chestnut extruded products would be an exclusive option to already existing snacks in the market and can facilitate a new sphere in extruded product sector.

Process optimization of ultrasonic assisted extraction of betalains from red beet, <em>Beta vulgaris L.</em> waste stalks

Beetroot stalks are regarded as agroindustrial waste, despite their nutritious and colourant characteristics. The pigments found in beetroot waste stalks were extracted using an ultrasonication approach in this investigation. Multiple regression analysis was used to investigate and assess the individual and interaction effects of power intensity, solid-solvent ratio, and sonication period on the betalains. Under optimal conditions (power intensity of 79.801 W/cm2, solid-solvent ratio of 22.4 g/ml, and sonication time of 26.7 min), the maximum betacyanin (3 mg/g) and betaxanthin (4.36 mg/g) were achieved. All responses of betalains extracted from beetroot waste stalks showed a significant (P <0.05) influence of process factors. It was also revealed in the study that ultrasound assisted extraction had actual yield of betalains (betacyanin, 2.92 mg/g and betaxanthin 4.27 mg/g), total phenolic content (69.74 mg GAE/g), as well as superior antioxidant activity (76.32%), than traditional techniques, under optimal conditions of independent process variables.