Aqueous Extraction Process Research Articles

Using Short‐Wave Infrared Radiation to Improve Aqueous Enzymatic Extraction of Peanut Oil: Evaluation of Peanut Cotyledon Microstructure and Oil Quality

In this study, the effects of short‐wave infrared radiation (SIR) on enzyme‐assisted aqueous extraction process (EAEP) of peanut oil (PO) are investigated, including peanuts cotyledon cells mircrostructure and yield as well as quality of extracted PO. GC‐flash electronic nose (EN) combined with principal components analysis (PCA) is applied to select conditions for SIR process. The appropriate roasting condition based on the overall flavor is determined as 150 °C for 55 min. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are used to investigate the effects of SIR on cotyledon microstructure. The results demonstrated that SIR damaged the cell microstructure and oil body membrane, and the extraction of oil is facilitated. Accordingly, the oil yield increased significantly by 8.74% compared to that of the control (p < 0.05). Further analysis on the quality properties of PO revealed that the content of polyphenols of oil extracted from SIR roasted peanuts (2.79 ± 0.05 mg GAE kg−1) is 62.21% higher than that from the control. It is in consistent with the significantly enhanced oxidation stability of oil in the present study (p < 0.05). Furthermore, the variety and relative content of volatile compounds which contributed to a better overall flavor are greatly increased.Practical Applications: SIR as a mild and efficient roasting method could enhance the oil extraction yield in EAEP and improve the oxidation stability of the extracted oil. With the appropriate pre‐roasting of peanuts by SIR, the overall flavor of EAEP extracted peanut oil was improved. Its volatiles pattern was close to that of the commercial hot‐pressed PO. It was confirmed that SIR is a novel choice for roasting processing, as well as a potential and available pre‐roasting method of peanuts to improve the EAEP technology.In order to improve the enzyme‐assisted aqueous extraction process (EAEP) of peanut oil, short‐wave infrared radiation (SIR) to roast peanuts before the extraction process is used. SEM and TEM are employed to evaluate the roasting effects on cotyledon microstructure. Some chemical properties, the content of antioxidant compounds, and the flavor of extracted oil are assessed to show the effects on oil quality. The oil yield is also evaluated to explain the roasting effects together with the changes of the microstructure.

Profitability Analysis of Soybean Oil Processes.

Soybean oil production is the basic process for soybean applications. Cash flow analysis is used to estimate the profitability of a manufacturing venture. Besides capital investments, operating costs, and revenues, the interest rate is the factor to estimate the net present value (NPV), break-even points, and payback time; which are benchmarks for profitability evaluation. The positive NPV and reasonable payback time represent a profitable process, and provide an acceptable projection for real operating. Additionally, the capacity of the process is another critical factor. The extruding-expelling process and hexane extraction are the two typical approaches used in industry. When the capacities of annual oil production are larger than 12 and 173 million kg respectively, these two processes are profitable. The solvent free approach, known as enzyme assisted aqueous extraction process (EAEP), is profitable when the capacity is larger than 17 million kg of annual oil production.

Optimization of an Aqueous Extraction Process for Pomegranate Seed Oil

AbstractResponse surface methodology employing a five‐level, four‐variable central composite rotatable design was applied to study the effects of extraction time, extraction temperature, pH and water/solid ratio on the extraction yield of pomegranate seed oil using an aqueous extraction approach. In addition, quality indices, fatty acid composition and antioxidant activity of the obtained oil were studied and compared with those of typical hexane‐, cold press‐ and hot press‐extracted oil. Aqueous extraction resulted in the maximum oil recovery of 19.3% (w/w), obtained under the following critical values: water/solid ratio (2.2:1.0, mL/g), pH 5.0, extraction temperature = 63 °C and extraction time = 375 min. This yield is lower than that obtained via hexane extraction (26.8%, w/w) and higher than the yields from cold press (7.0%, w/w) and hot press (8.6%, w/w) extraction. A comparison of the characteristics of the oils based on extraction method revealed that the unsaturated fatty acid content was highest for the oil obtained by aqueous extraction. In addition, higher levels of iodine and peroxide and lower levels of acid, p‐anisidine and unsaponifiable matter were observed. The oil obtained with aqueous extraction also exhibited higher antioxidant activity than oils obtained by hexane or hot press extraction.

Celluclast 1.5L pretreatment enhanced aroma of palm kernels and oil after kernel roasting.

The aroma of palm kernel oil (PKO) affects its applications. Little information is available on how enzymatic modification of palm kernels (PK) affects PK and PKO aroma after kernel roasting. Celluclast (cellulase) pretreatment of PK resulted in a 2.4-fold increment in the concentration of soluble sugars, with glucose being increased by 6.0-fold. Higher levels of 1.7-, 1.8- and 1.9-fold of O-heterocyclic volatile compounds were found in the treated PK after roasting at 180 °C for 8, 14 and 20 min respectively relative to the corresponding control, with furfural, 5-methyl-2-furancarboxaldehyde, 2-furanmethanol and maltol in particularly higher amounts. Volatile differences between PKOs from control and treated PK were also found, though less obvious owing to the aqueous extraction process. Principal component analysis based on aroma-active compounds revealed that upon the proceeding of roasting, the differentiation between control and treated PK was enlarged while that of corresponding PKOs was less clear-cut. Celluclast pretreatment enabled the medium roasted PK to impart more nutty, roasty and caramelic odor and the corresponding PKO to impart more caramelic but less roasty and burnt notes. Celluclast pretreatment of PK followed by roasting may be a promising new way of improving PKO aroma. © 2017 Society of Chemical Industry.

Studies on jackfruit seed starch as a novel natural superdisintegrant for the design and evaluation of irbesartan fast dissolving tablets

BackgroundIn the present investigation, an attempt was made to isolate starch from jackfruit seed powder and utilize it as a superdisintegrant to design fast dissolving tablets of irbesartan. MethodsStarch was isolated from jackfruit seeds via aqueous and alkali extraction processes and evaluated for its physicochemical properties, for phytochemical tests, and for acute toxicity studies. Irbesartan fast dissolving formulations were prepared using the wet granulation technique. ResultsAcute toxicity studies for the extract indicated that all rats were healthy with no physiological changes in their behavior. The prepared irbesartan tablet formulations were found to be stable according to the Indian Pharmacopoeia-specified limits for postcompression parameters. From in vitro dissolution studies, it was observed that formulations F5 and F8 containing 5% w/w of alkali extracted starch and 5% w/w of croscarmellose sodium showed faster disintegration and improved dissolution rate compared with the other formulations. Fourier transfer infrared spectroscopic and differential scanning colorimetric analysis performed on optimized formulations indicated that there were no major interactions between the drug and excipients. Accelerated stability studies carried out on optimized formulations showed all tablets to be stable. ConclusionThe tablets prepared from jackfruit seed starch as superdisintegrant were found to be suitable for preparation of fast dissolving tablets.

Extraction and Film Properties of Kafirin from Coarse Sorghum and Sorghum DDGS by Percolation

The high cost of kafirin and zein restricts their use for bioplastic and food applications. Effective, simple, and rapid kafirin/zein isolation processes are required. Here a percolation‐type aqueous ethanol solvent extraction process from coarse meals (grits) and coarse sorghum distillers dried grains and solubles (DDGS) for kafirin and zein isolation employing a low ratio of extractant to meal (2.5:1) was investigated, which is potentially applicable in the grain bioethanol industry. Postextraction filtration times were more than twice as fast using coarse meals compared with fine flours. Washing the meals prior to extraction to remove starch improved protein preparation purity to 73–85% compared with 68–72% for unwashed meals. Hence, no subsequent filtration or centrifugation step is required to clean up the kafirin/zein solution prior to solvent evaporation. With a single extraction step, kafirin/zein yields were 48% (protein basis) for DDGS and 53–70% for washed sorghum/maize meals. Cast films were used as a model bioplastic system to evaluate extracted kafirin/zein functional properties. DDGS kafirin films had rough surfaces but had the lowest water uptake and in vitro digestibility, owing to heat‐induced disulfide crosslinking during DDGS processing. Extraction by percolation using coarse meal/DDGS has potential to improve kafirin/zein viability.

Dissolving Lignin in Water through Enzymatic Sulfation with Aryl Sulfotransferase.

We introduce the concept of using site-specific sulfation of various lignins for increasing their aqueous solubility and thereby their processability. Using p-nitrophenylsulfate as a sulfate source and an aryl sulfotransferase enzyme as catalyst, lignins are easily sulfated at ambient conditions. We demonstrate the specific sulfation of phenolic hydroxyl groups on five different lignins: Indulin AT (Kraft softwood), Protobind 1000 (mixed wheat straw/Sarkanda grass soda) and three organosolv lignins. The reaction proceeds smoothly and the increase in solubility is visible to the naked eye. We then examine the reaction kinetics, and show that these are easily monitored qualitatively and quantitatively using UV/Vis spectroscopy. The UV/Vis results are validated with 31 P NMR spectroscopy of the lignin phenol groups after derivatization with phosphorylation reagent II. In general, the results are more significant with organosolv lignins, as Kraft and soda lignins are produced from aqueous lignocellulose extraction processes.

Demulsification of oil-rich emulsion and characterization of protein hydrolysates from peanut cream emulsion of aqueous extraction processing

In this study, the effect of physical (heating, freezing-thawing), salts (CaCl2 and NaCl) and enzymatic treatments (Protex 6L, Protex 7L, Protex 50FP, Alcalase 2.4L, Papain, phospholipase and Amylase) on free oil recovery yield from peanut cream emulsion of aqueous extraction processing (AEP) were investigated. Proteases were more effective on demulsification than salts and physical methods. The peanut protein hydrolysates were a by-product of AEP. Researches on hydrolysates related to the commercial application of AEP. The degree of hydrolysis and molecular weight (MW) distribution of proteins in cream emulsion were comparable to each other when treating by proteases. Analysis of changes in protein solubility, emulsifying properties, subunit and secondary structure distribution indicated that all the solubility of protein hydrolysates was improved after enzymatic treatment, the emulsifying activity indexes (EAI) of all the hydrolysates were enhanced with the increment in enzymatic time, but only that treated by Protex 50FP significantly higher than control (native proteins in cream emulsion). Moreover, the emulsifying stability indexes (ESI) of all hydrolysates were less than control. Additionally, the results of secondary structure suggested that hydrolysates had decreased the levels of α-helix, β-sheet and β-turn and increased unordered coils level.

Near-Infrared Spectroscopy Combined with Multivariate Calibration to Predict the Yield of Sesame Oil Produced by Traditional Aqueous Extraction Process

Sesame oil produced by the traditional aqueous extraction process (TAEP) has been recognized by its pleasant flavor and high nutrition value. This paper developed a rapid and nondestructive method to predict the sesame oil yield by TAEP using near-infrared (NIR) spectroscopy. A collection of 145 sesame seed samples was measured by NIR spectroscopy and the relationship between the TAEP oil yield and the spectra was modeled by least-squares support vector machine (LS-SVM). Smoothing, taking second derivatives (D2), and standard normal variate (SNV) transformation were performed to remove the unwanted variations in the raw spectra. The results indicated that D2-LS-SVM (4000–9000 cm−1) obtained the most accurate calibration model with root mean square error of prediction (RMSEP) of 1.15 (%, w/w). Moreover, the RMSEP was not significantly influenced by different initial values of LS-SVM parameters. The calibration model could be helpful to search for sesame seeds with higher TAEP oil yields.

Ultrasound-Assisted Aqueous Enzymatic Extraction of Oil from Pomegranate Seeds

Pomegranate seed oil presents nutraceutical properties. Industrial processes for extraction of edible oils from seeds generally involve a solvent extraction step. Safety considerations on the use of organic solvents prompted attempts to develop aqueous extraction. However, aqueous extraction processes are usually characterized by low oil yields. The objective of this work was to overcome these low yields by using enzymes. The pomegranate seeds were treated with two enzymes—cellulase and Peclyve V. The extraction temperature, the time, the enzyme concentration, and the water/seeds ratio were varied between 35 and 55 °C, 2 and 8 h, 2 and 4 % w/w, and 2/1 and 6/1 mL/g, respectively. The optimum yield accomplished (15.33 g oil/100 g dry seeds at 2 h or 81 % oil recovery) was comparable to the yields obtained by other extraction methods, such as normal stirring, cold pressing, superheated fluid extraction, indirect ultrasound-assisted extraction and supercritical extraction, (4.29–25.11 g oil/100 g seeds) at similar or longer extraction times (10 min–72 h). In addition, this work studies the enhancement of aqueous enzymatic extraction of pomegranate seed oil by ultrasound probe. It was found that only 10 min in water are needed to recover oil with a yield of 18.15 g oil/100 g dry seeds, a value similar to or higher than those of the conventional procedures. Thus, the use of ultrasounds increased the yield of enzymatic extraction by 18.4 % and reduced the extraction time by 91.7 %.

Destabilization of Emulsion Formed During Aqueous Extraction of Peanut Oil: Synergistic Effect of Tween 20 and pH

AbstractTo destabilize the emulsion formed during aqueous extraction processing (AEP) of peanuts, Tween and Span series surfactants (Tween 20, Tween 80, Span 20, and Span 80) were used alone or in combination to break the emulsion. Results indicate that only Tween surfactants had a pronounced demulsifying effect that was dependent on Tween concentration and system pH. When 1.2 wt% Tween 20 aqueous solution was used for oil extraction at pH 10.0, the highest free oil yield was achieved at 76.1 %, which was similar to the oil recovery of using proteases as a destabilization agent. The results obtained using a model emulsion system containing peanut oil and Tween 20/peanut protein isolates (PPI) showed that when Tween 20 and PPI coexisted in extraction medium at pH 10.0, the dynamic interfacial tension and droplet size distribution curves were very similar to those when Tween 20 was used alone, suggesting that Tween 20 dominated at the interface, instead of PPI. Destabilization of the model emulsions relied on three important factors: inclusion of Tween 20 at the initial mixing stage, high pH, and a gentle mixing speed. A synergistic destabilization mechanism of using Tween 20 at high pH during AEP was proposed. The discovery of Tween 20 as an effective demulsifier significantly contributes to the development of AEP of oilseeds.

Response surface methodology to optimize enzyme-assisted aqueous extraction of maize germ oil.

The present study was aimed at optimizing the enzyme assisted aqueous extraction (EAAE) process for extraction of maize germ oil. The different EAAE process parameter viz., pH of the slurry, seed to water ratio, the temperature of incubation and time of hydrolysis were optimized for improving oil recovery and oil quality. The combined effect of independent variables on recovery of oil, time taken for oil extraction and various quality parameters were studied using response surface methodology. The designed experimental runs were conducted to obtain the optimal conditions as 5.85pH of slurry, 1:6.92 seed to water ratio, 45.12°C temperature of incubation and 1h time of hydrolysis. Oil extracted under these conditions was light yellowish in color and had a pleasant nutty taste, with maximum oil recovery of 70%. The extraction variables viz., pH of slurry, seed to water ratio, the temperature of incubation had a significant effect on recovery of oil and various quality characteristics, however the time of hydrolysis had a non significant effect.

Separation and Purification of Furfuryl Alcohol Monomer and Oligomers Using a Two-Phase Extracting Process

Aqueous two-phase extraction processes were applied for the first time for the separation and purification of furfuryl alcohol monomer and oligomers. Deionized water was used as the liquid–liquid extraction solvent whereas magnesium sulfate acted as the salting-out reagent. Furfuryl alcohol preferentially partitioned to the water phase and could be further extracted from its aqueous solution due to the decreased solubility in salt rich phase. Various influences, such as partition coefficient and extractability, were studied during the liquid–liquid extraction. The extraction by using deionized water resulted in a high oligomer content around ∼94 wt % in the separated furfuryl alcohol oligomer solution whereas the salting-out furfuryl alcohol showed a purity of ∼92 wt %.

Characterization and demusification of cream emulsion from aqueous extraction of peanut

In this study, the effect of aqueous extraction processing (AEP) and enzyme-assisted aqueous extraction processing (EAEP) on peanut oil yield was investigated. Only 34.53 ± 4.07% of free oil was recovered when using AEP without demulsification. In the case of EAEP, 89.31 ± 0.90% of free oil was obtained (1.5% w/w Alcalase 2.4L) without demulsification. Meanwhile, the protein yields of AEP and EAEP were similar, 84.10 ± 0.22% and 80.62 ± 0.92%, respectively. The efficiencies of enzymes (Protex 6L, Protex 7L, Protex 50FP, Alcalase 2.4L, Papain and Lecitase® Ultra) and pH of the released oil from peanut pastes were evaluated. Papain and Protex 50FP were effective in destabilizing the cream emulsion (93.10 ± 0.79% and 94.89 ± 0.19%, respectively). Adjusting the pH of the cream emulsion to the isoelectric point of peanut proteins also destabilized the cream with 85.71% of free oil recovery. Furthermore, the changes in the microstructure of cream emulsion during enzymatic demusification were observed by confocal laser scan microscope (CLSM). The interface tension decreased with the increase in enzymatic treatment time. For surface hydrophobicity (H0), cream emulsions treated by Protex 50FP and Papain had a remarkable decrease. Papain treated cream emulsion had a smaller H0 than that of Protex 50FP due to the protein aggregations formed during adjusting pH value to 4.5. This might have hindered the efficiency of protein hydrolysis and left more basic arachin (MW 18–24 kDa) which have more hydrophobic groups.

Parameters affecting enzyme-assisted aqueous extraction of extruded sunflower meal

Microscopic observation of sunflower meal before and after extraction indicated that extensive cellular disruption was achieved by extrusion, but that unextracted oil remained sequestered as coalesced oil within the void spaces of disrupted cotyledon cells. A full factorial design experiment was defined to develop aqueous extraction processing (AEP) with and without enzymes to improve vegetable oil extraction yields of extruded sunflower meal. This experimental design studied the influence of four parameters, agitation, liquid/solid (L/S) ratio, and cellulase and protease addition, on extraction yield of lipid and protein. Agitation and addition of cellulases increased oil extraction yield, indicating that emulsification of oil and alteration of the geometry of the confining cellular matrix were important mechanisms for improving yields. Protease and liquid-solid ratio of the extraction mixture did not have significant effects, indicating key differences with previously established soy oil extraction mechanisms. Maximum yields attained for oil and protein extraction were 39% and 90%, respectively, with the aid of a surfactant.

Solvent removal from cyclohexane‐extracted oil sands gangue

AbstractSolvent extraction of bitumen from the Alberta oil sands has the potential to overcome the shortcomings of the current aqueous extraction process by reducing fresh water demand and eliminating tailings ponds. Bitumen is recovered as a solution, leaving behind the solids (or gangue) with a residual solvent and water from the original ore. Removing the solvent from the gangue is a crucial step that involves evaporation of volatile material (cyclohexane) from a porous matrix in the presence of a less volatile immiscible phase (water). In this study, we examined the effects of relative humidity, temperature, and the addition of water during cyclohexane extraction on the extent of cyclohexane removal from the extraction gangue. The drying curves showed two constant‐rate periods, with the initial period mainly removing cyclohexane, and the second mainly removing water. The initial drying rate of gangue in an environmental chamber was 2.7 times faster than drying in a fume hood due to the stronger convective currents in the chamber produced by its fan. The initial drying rate was independent of the relative humidity, which was in the range of 30–90 %, but the residual cyclohexane content in the gangue increased at high relative humidity. The addition of water to oil sands prior to cyclohexane extraction increased the residual cyclohexane in the gangue, likely by forming a barrier to efficient evaporation.

Effects of roasting temperatures and grinding type on the yields of oil and protein obtained by aqueous extraction processing

A three cylindrical roll crusher was used in this study to solve the comminution problem and to improve oil and protein yields in aqueous extraction processing (AEP) of peanuts. We combined confocal laser scanning microscopy (CLSM) and particle size distribution analysis to investigate the effect of different peanut processing material on oil and protein extraction. A proper roasting treatment (150 °C) is beneficial to oil extraction yield. However, the protein yield has been declining from 84.33% to 51.40% with the increase of roasting temperature from (130 °C–210 °C). The optimal average particle size of peanut paste in AEP was 15.2 μm which could hardly find intact oil bodies by CLMS. Nevertheless, the remained intact of protein body still could be found in insoluble fraction. In AEP, highest free oil yield (92.2%) was achieved with roasted peanut (150 °C, 20 min) using 1: 5 solid to liquid ratio (twice ground peanut pastes/water), pH 9, 60 °C for 2 h and demusification by adding 0.5% (w/w) Protex 50FP at pH 4.5 and incubating at 50 °C for 2 h. Without roasting treatment, the oil contents of insoluble and residual cream fractions from AEP were highly correlated with their protein contents (R2 = 0.8724, 0.9178, respectively). Additionally, the exposure of interior hydrophobic groups of peanut protein adhere more oil to the protein body surface, which may have led to increment in the oil content of insoluble fraction.

Biogenic synthesis of iron nanoparticles using Amaranthus dubius leaf extract as a reducing agent

The biogenic synthesis of nanosize powder is of great interest due to its multifunctional applications and easy and eco-friendly process. The biosynthesis of nanosize iron particles using Amaranthus dubius leaf aqueous extracts that are reduced from ferric chloride was investigated. A. dubius aqueous leaf extraction process parameters were optimized based on the antioxidant capacity for attaining efficient extract. The leaf extract contains a rich source of amaranthine and phenolic compounds that are used as reducing agents. The effects of different process parameters like pH, temperature, concentration of leaf extract and time on the nanoparticle synthesis were examined. The synthesised nanoparticle size, morphology, crystallinity, composition, and stability were investigated. Results showed that A. dubius extract mediated nanoparticles are in spherical shape with a cubic phase structure and a diameter range from 43 to 220nm with less aggregation. A. dubius and sodium borohydride mediated iron nanoparticles for decolouration efficiency against methylene orange and antioxidant against 1, 1-diphenyl-2-picrylhydrazyl were studied.

On-chip aqueous two-phase system (ATPS) formation, consequential self-mixing, and their influence on drop-to-drop aqueous two-phase extraction kinetics

Aqueous two-phase systems (ATPSs) allow an advantageous aqueous two-phase extraction process (ATPE), a special type of liquid–liquid extraction. Compared with conventional liquid–liquid extraction using aqueous/organic extraction media, ATPE is known to provide relatively easy mass transfer and a gentle environment for biological separation applications. Considering the recent interest in microscale ATPE, we aimed to study (i) the potential of preparing ATPS droplets on a digital microfluidic device, and (ii) the influence of the fluidic dynamics created during the formation of ATPS, with the goal of enhancing on-chip ATPE process. On-chip ATPS formation was evaluated by preparing a series of ATPSs on electrowetting on dielectric digital microfluidic chips and comparing their characteristics with the same ATPSs prepared at macroscale using conventional procedures. An enhanced on-chip drop-to-drop ATPE process was achieved by incorporating a self-mixing condition created during ATPSformation. Results indicate a successful on-chip ATPS preparation as well as enhanced extraction performance by self-mixing in the absence of forced mixing. Findings of this research suggest an alternative, simple, yet adequate technique to provide mixing for on-chip applications, such as sample preparation in portable microfluidics, for which it is unfavorable to implement complicated mixing sequences or complex device geometries.

Effect of co-products of enzyme-assisted aqueous extraction of soybeans on ethanol production in dry-grind corn fermentation

Enzyme-assisted aqueous extraction processing (EAEP) is an environmentally-friendly alternative to solvent and mechanical oil extraction methods, and can achieve ∼97% oil recovery from soybeans. The present study utilized soy skim (protein rich) and insoluble fiber (IF; carbohydrate rich), both co-products of EAEP, in dry-grind corn fermentation. The effects of adding soy skim and untreated IF (UIF), either separately or together, and adding pretreated IF (TIF), on ethanol production were investigated. Maximum ethanol production was achieved when UIF and skim were slurried together (corn-to-UIF ratio 1:0.16; skim-to-UIF ratio 6.5:1) and when fiber-hydrolyzing enzymes were added to corn fermentation. This modification to corn fermentation increased ethanol yield by 20%, ethanol production rate by 3%, and decreased fermentation time by 38h compared to corn-only fermentation. An attempt was also made to utilize pentoses (from soy skim and IF) in integrated corn-soy fermentation slurry by an additional Escherichia coli KO11 fermentation step.