Extraction kinetics modeling of wheat germ oil supercritical fluid extraction

Exogenous microbubbles contribute to valorization of microalgal compounds by ultrasound-assisted extraction

Ultrasound-assisted extraction (UAE) shows great potential in exploiting microalgal compounds. However, upgrading the extraction system lacks concerns. This study proposes a novel sono-reactor featuring a microbubble distributor for increasing bubble abundance and correspondingly improving microalgal compound extraction. Results indicate that protein concentrations increase with ultrasound powers and extraction time while an optimized gas flow rate exists. The optimal parameters by Box-Behnken design are power 646.0 W, nitrogen flow rate 25.0 mL/min, and time 40.0 min, with an optimal protein concentration of 249.1 mg/L - a substantial improvement over gas-free extraction. The strategic increase in bubble abundance enhances microalgal compound extraction efficiency and extraction kinetics The system innovation will contribute to the advancement of bioresource utilization and sustainability.

Ultrasound-induced cell disintegration and its ultrastructure characterization for the valorisation of Chlorella pyrenoidosa protein

Chlorella pyrenoidosa (CP) has great potential for feeding future demands in food, environment, energy, and pharmaceuticals. To achieve this goal, the exploitation of emerging efficient technique such as ultrasound-assisted extraction (UAE) for CP nutrient enrichment is crucial. Here, UAE is deployed for high-efficient CP protein (CPP) valorisation. Compared to conventional solvent extraction (CSE), remarkable mass transfer enhancements with 9-time protein yields and 3-time extraction rate are achieved by ultrasonic cavitation in UAE, indicating UAE can drastically shift intracellular nutrients including proteins and pigments to solvent. Cell morphology and ultrastructure show the different responses of cell wall and membrane, indicating that the cell membrane may play a role in the extraction process, based on which the extremely-low efficiency of CSE and high efficiency of UAE are highlighted. This study provides a solution for future food crisis by extracting CPP and may open a new discussion field in ultrasonic extraction.

Lipid Extracts Obtained by Supercritical Fluid Extraction and Their Application in Meat Products

Supercritical fluid extraction (SFE) has been recognized as the green and clean technique without any negative impact on the environment. Although this technique has shown high selectivity towards lipophilic bioactive compounds, very few case studies on the application of these extracts in final products and different food matrices were observed. Considering the recent developments in food science and the increasing application of supercritical extracts in meat products in the last decade (2012–2022), the aim of this manuscript was to provide a systematic review of the lipid extracts and bioactives successfully obtained by supercritical fluid extraction and their application in meat products as antioxidant and/or antimicrobial agents. Lipophilic bioactives from natural resources were explained in the first step, which was followed by the fundamentals of supercritical fluid extraction and application on recovery of these bioactives. Finally, the application of natural extracts and bioactives obtained by this technique as functional additives in meat and meat products were thoroughly discussed in order to review the state-of-the-art techniques and set the challenges for further studies.

Recovery of biologically active compounds from stinging nettle leaves part I: Supercritical carbon dioxide extraction

Stinging nettle is annual plant from Urticaceae family used as food and medicine. Due to the nonsufficient data, this work aimed to isolate the bioactive compounds from the stinging nettle leaves by supercritical carbon dioxide. Extracts were analyzed and assessed for antioxidant and cytotoxic activities. Main fatty acids were α-linolenic (31.06-58.42 mg/g E), palmitic (9.17-13.12 mg/g E), and linoleic (10.93-16.51 mg/g E) acids. Chlorophylls (33.00-7365.11 mg/100 g E) and carotenoids (166.88-722.62 mg/100 g E) were also found in all samples. Four empirical kinetic equations were effectively utilized for kinetic modeling of supercritical fluid extraction. As per proper statistical features, empirical models show good concurrence with experimental data. The numerical modeling of a process is gainful to foresee the process conduct and furthermore extend the methodology from laboratory to industrial scales. The principal component analysis was used to visualize the fatty acids profile, antioxidant capacity, and cytotoxic activity of extract.

Determination of free fatty acids in crude vegetable oil samples obtained by high-pressure processes

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Free fatty acid profile in vegetable oils was determined.

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The extraction process may influence the free fatty acid profile.

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Linoleic and oleic acids were present in higher proportions.

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The methodology applied was satisfactory for qualitative analysis.

This study determined the total acidity, fatty acids profile (TFAs), and free fatty acids (FFAs) present in sunflower and soybean oils obtained by green processes (supercritical carbon dioxide-scCO₂ and pressurized liquid extraction-PLE). The determination of the primary fatty acids responsible for product acidity can provide a higher quality product. Sunflower (scCO₂/PLE-ethanol) and soybean (PLE-ethanol/PLE-hexane) samples were evaluated. The TFAs profile was determined by gas chromatography - mass spectrometry. The total FFAs content was determined by titrimetric method. For the qualitative determination of the FFAs present in the oils, a new technique capable of repeatably identifying the main FFAs was applied, using GC/MS. The primary fatty acids (palmitic, stearic, oleic, linoleic, eicosenoic, and linolenic) were present in all samples, both as TFAs and FFAs. However, fatty acids of lesser intensity showed variations. The applied methodology provided relevant data on the FAs that cause acidity in vegetable oils obtained by green processes.

Supercritical Fluid Extraction Kinetics of Cherry Seed Oil: Kinetics Modeling and ANN Optimization

This study was primarily focused on the supercritical fluid extraction (SFE) of cherry seed oil and the optimization of the process using sequential extraction kinetics modeling and artificial neural networks (ANN). The SFE study was organized according to Box-Behnken design of experiment, with additional runs. Pressure, temperature and flow rate were chosen as independent variables. Five well known empirical kinetic models and three mass-transfer kinetics models based on the Sovová’s solution of SFE equations were successfully applied for kinetics modeling. The developed mass-transfer models exhibited better fit of experimental data, according to the calculated statistical tests (R², SSE and AARD). The initial slope of the SFE curve was evaluated as an output variable in the ANN optimization. The obtained results suggested that it is advisable to lead SFE process at an increased pressure and CO₂ flow rate with lower temperature and particle size values to reach a maximal initial slope.

Extraction of Peppermint Essential Oils and Lipophilic Compounds: Assessment of Process Kinetics and Environmental Impacts with Multiple Techniques

Consumers are becoming more mindful of their well-being. Increasing awareness of the many beneficial properties of peppermint essential oil (EO) has significantly increased product sales in recent years. Hydrodistillation (HD), a proven conventional method, and a possible alternative in the form of microwave-assisted hydrodistillation (MWHD) have been used to isolate peppermint EO. Standard Soxhlet and alternatively supercritical fluid (SFE), microwave-assisted, and ultrasound-assisted extraction separated the lipid extracts. The distillations employed various power settings, and the EO yield varied from 0.15 to 0.80%. The estimated environmental impact in terms of electricity consumption and CO₂ emissions suggested that MWHD is an energy efficient way to reduce CO₂ emissions. Different extraction methods and solvent properties affected the lipid extract yield, which ranged from 2.55 to 5.36%. According to the corresponding values of statistical parameters, empiric mathematical models were successfully applied to model the kinetics of MWHD and SFE processes.

Supercritical Fluid Extraction of Pesticides and Insecticides from Food Samples and Plant Materials

The principal intention of this study is presenting the attempts carried out for extracting, separating, and determining of the pesticide and insecticide residues existing in food and plant samples. In this regard, a set of content, including the explanations about the supercritical fluid extraction (SFE), supercritical fluid chromatography, and various types of pesticides are indicated. Besides, the parameters affecting the pesticides extraction composed of temperature, pressure, modifier, drying agent, and so on are discussed. Also, examples of insecticides extraction by SFE technique as an important subset of pesticides are indicated. Along with these items, some interesting works, concerning the innovations implemented in the field of SFE of pesticide and insecticide residues from foodstuff and plants are depicted.