Liquid–liquid equilibria for systems composed of rice bran oil and alcohol-rich solvents: Application to extraction and deacidification of oil

The liquid–liquid equilibria of systems composed of rice bran oil, free fatty acids, ethanol and water were investigated at temperatures ranging from 10 to 60 °C. The results of the present study indicated that the mutual solubility of the compounds decreased with an increase in the water content of the solvent and a decrease in the temperature of the solution. The experimental data set was correlated by applying the UNIQUAC model. The average variance between the experimental and calculated compositions was 0.35%, indicating that the model can accurately predict behavior of the compounds at different temperatures and degrees of hydration. The adjustment of interaction parameters enables both the simulation of liquid–liquid extractors for deacidification of vegetable oil and the prediction of phase compositions for the oil and alcohol-rich phases that are generated during cooling of the stream exiting the extractor (when using ethanol as the solvent).     

Extraction and purification of free cholesterol from some egg-containing food by on-line supercritical fluid extraction – solid-phase extraction

Two methods for the extraction and determination of free cholesterol in some egg-containing food samples were compared: the classical Soxhlet method and a supercritical carbon dioxide extraction (at 338 bar and 40vv°C) coupled on-line with solid-phase extraction (SPE with a solid trap packed with an ODS stationary phase). Egg noodles, biscuits and sweet snacks were homogenised and added to the internal standard and anhydrous sodium sulphate. Part of each sample was extracted by on-line supercritical fluid extraction - solid-phase extraction (SFE-SPE) and the remaining part was extracted by the classical method using petroleum ether. A further purification after the Soxhlet extraction was performed by SPE. Free cholesterol was determined in both the off-line Soxhlet-SPE fraction and the on-line SFE-SPE extract with capillary gas chromatography after silylation. The two extraction methods gave similar results. However, on-line SFE-SPE represents a valid alternative to the Soxhlet method because it shows important advantages, such as a short analysis time and low solvent consumption.     

Flaxseed oil – Whey protein isolate emulsions: Effect of high pressure homogenization

The effect of high-pressure homogenization (20–100 MPa) and the number of homogenization cycles (1–7) on the stability of flaxseed oil - whey protein isolate emulsions was evaluated. All the emulsions were stable to creaming for at least 9 d of storage. An increase in homogenization pressure from 20 to 80 MPa and number of passes through the homogenizer up to 3, decreased the mean droplet size of the O/W emulsions despite the higher polydispersity. Emulsions homogenized at lower pressures (20 MPa) showed a monomodal distribution of the particles, whereas, an increase in pressure to 80 MPa led to a bimodal distribution, indicating droplets coalescence. High-pressure homogenization (80 MPa) and an increase in the number of homogenization cycles, led to the formation of high molecular weight aggregates (>200 kDa), which favored an increase in viscosity of the emulsions. The increase in homogenization pressure also increased the formation of primary oxidation products, which could be explained by the increase in temperature and in the surface area of the droplets.     

α-Glucosidase and α-amylase inhibitors from seed oil: A review of liposoluble substance to treat diabetes

One of the effective managements of diabetes mellitus, in particular, noninsulin-dependent diabetes mellitus, is to retard the absorption of glucose by inhibition of carbohydrate hydrolyzing enzymes, such as α-glucosidase and α-amylase, in the digestive organs. Currently, there is renewed interest in plant-based medicines and functional foods modulating physiological effects in the inhibition of α-glucosidase and α-amylase. Accordingly, inhibitors of α-glucosidase or α-amylase derived from various sources have also been isolated, and majority of phenolic compounds and their effects have been investigated in animals as well. As such, when the presence of α-glucosidase inhibitor in many foodstuffs was screened for, we found that vegetable seed oil also strongly inhibited α-glucosidase and α-amylase. Seed oil is an important source of liposoluble constituents with potential for inhibition of these enzymes, hence can also be used as therapeutic or functional food sources. Therefore, this review is aimed at highlighting the main liposoluble classes of α-glucosidase and α-amylase inhibitors, but it is not intended to be an exhaustive review on the subject.     

Solid-state fermentation of apple pomace using Phanerocheate chrysosporium – Liberation and extraction of phenolic antioxidants

Apple pomace is a by-product from the apple processing industry and can be used for the production of value-added phenolic compounds. A study was carried out to understand the changes and liberation of phenolic compounds and improvement in antioxidant activity during solid-state fermentation of apple pomace using Phanerocheate chrysosporium. The solid-state fermentation of apple pomace using P. chrysosporium mobilised the polyphenolic compounds and improved the nutraceutical properties. The polyphenol content in acetone extract increased and the results were statistically significant (P < 0.05) from 4.6 to 16.12 mg GAE/g dry weight during solid-state fermentation. The effect of various solvents, temperature, time and detergents were also investigated for the extraction of polyphenolics by ultrasonication and microwave-assisted extraction methods. The polyphenol content of the extracts was found to be in the range of 5.78–16.12 mg GAE/g DW of samples, depending on the solvent, extraction time and temperature. Antioxidant activities of polyphenol extracts were tested using the 2,2-diphenyl-1-picryhydrazyl (DPPH) radical methods, where the IC₅₀ ranged from 12.24 to 23.42 μg DW sample, depending on the extraction conditions and the antioxidant activities correlated well with the polyphenol concentrations.     

Brominated vegetable oil in soft drinks – an underrated source of human organobromine intake

In North America brominated vegetable oil (BVO) is frequently used as a clouding agent for soft drinks. BVO containing soft drinks have a market share of about 15% in the USA. In our study we analysed several soft drinks from North America for BVO and calculated exposures from our results and consumption data. Based on a mean content of 8 ppm in BVO-containing soft drinks, the average daily human intake of BVO exceeds the intake of other organobromine compounds, e.g., polybrominated diphenyl ethers (PBDEs), by >4000 times for adults and >1000 times for children. By comparing the patterns of the brominated fatty acids (BFA) in the soft drinks, we were able to distinguish three BVO products used by three soft drink manufacturers. The analysis also revealed that the predominant BFAs in BVO are the Br₂-18:0 (bromination product of oleic acid) and Br₄-18:0 (bromination product of linoleic acid).     

Essential oil composition,phenolic compound,and antioxidant potential of Inulaviscosa as affected by extraction process

The purpose of this study was to compare the essential oil composition of Inula viscosa leaves by hydrodistillation (HDE), ultrasonic (UDE) and solvent (SE) extractions followed by hydrodistillation. The total polyphenol and flavonoid contents and their antioxidant effects were studied by different solvent of extraction: ethanol (ET), ethyl acetate (EA), methanol (ME) and aqueous (AE). The principal compounds for HDE were: 2-hexenal (3.70%), caryophyllene oxide (3.11%), γ-selinene (3.09%), 3-hexen-1-ol (2.00%), eugenol (1.70%) and trans-caryophyllene (1.34%), while for UDE were: γ-selinene (5.68%), caryophyllene oxide (4.87%), trans-caryophyllene (1.99%) and nerolidol (1.74%). The oil obtained by SE was shown to contain tridecane (3.89%), dodecane (3.08%), trans-caryophyllene (2.94%), caryophyllene oxide (2.56%) and nerolidol (2.53%). Significant changes on phenolic contents were found between the different solvent of extraction. ME and AE extracts led to the highest total polyphenol (PHL) and flavonoid (FL) amounts. The anti-radical activity and reducing power were maximal in AE and ME extract. HPLC examination established that the ferulic acid as major phenolic acid in ME and AE fractions, whereas luteolin was the main compound of EA and ET fractions.     

Effects of Gac aril microwave processing conditions on oil extraction efficiency,and β-carotene and lycopene contents

The effects of Gac oil extraction conditions including microwave power, microwave time, steaming time and hydraulic pressure on extraction efficiency (EE), and β-carotene and lycopene contents were studied. It was found that the EE, and β-carotene and lycopene contents could be enhanced by suitable extraction conditions. Microwave drying was found to be better than air drying for pretreatment. Moisture content after drying and steaming between 8% and 11% (wt/wt) were best for pressing. Results showed that the most suitable conditions for Gac oil extraction from 900 g samples were microwave power of 630 W, microwave time of 65 min, steaming time of 20 min and hydraulic pressure of 170 kg/cm². Under these conditions, the highest EE of 93% was achieved while Gac oil contained the highest content of β-carotene and lycopene at 140 and 414 mg/100 mL, respectively.     

An integrated process for utilization of pomegranate wastes — Seeds

In this work, a new method for pomegranate seeds application was developed based on the ultrasound-assisted extraction of seed oil and its subsequent encapsulation by spray drying. Extraction temperature, solvent/solid ratio, amplitude level, and pulse duration/pulse interval ratio were the factors investigated with respect to extraction yield. Ultrasound was sound to increase extraction yield, but mainly to shorten the treatment time by over 12 times. Different materials were used as encapsulating agents. Ratio of core to wall material, inlet air temperature, drying air flow rate, and feed solids concentration were the factors investigated with respect to encapsulation efficiency. The resulting microcapsules were evaluated in terms of moisture content, bulk density, and rehydration ability. The optimum operating conditions were found to be: wall material, maltodextrin/Tween 80; ratio of core to wall material, 0.23; inlet air temperature, 150 °C; drying air flow rate, 22.8 m³/h; feed solids concentration, 30% (w/w).Industrial relevancePomegranate seeds, a by-product of pomegranate juice and concentrate industries, present a wide range of pharmaceutical and nutraceutical properties. Therefore, the seeds could have more beneficial applications in food industries instead of being used as animal feed or in commercial cosmetic products. In this work, a new method for pomegranate seeds application was developed based on the ultrasound-assisted extraction of seed oil and its subsequent encapsulation by spray drying.     

Effect of pulsed electric fields – assisted extraction on anti-inflammatory and cytotoxic activity of brown rice bioactive compounds

The bioactive compounds of brown rice exhibit many beneficial health effects, ranging from antioxidant to cytotoxic activities. Pulsed Electric Field (PEF) pretreatment can significantly enhance their extraction, through the induction of the electro-permeabilization of the cell membranes.This paper aims to demonstrate that PEF-assisted extraction of brown rice enables not only enhanced yields of antioxidant compounds, such as γ-oryzanol, polyphenols and phenolic acids, and of saturated and unsaturated fatty acids, but also increased cytotoxic effects on cancer cells.Initially, the PEF-assisted extraction conditions have been defined by the assessment of the cell permeabilization index via impedance measurements and the DPPH antioxidant activity. Subsequently, the biological effects of PEF have been evaluated on the cytotoxicity and anti-inflammatory properties against human colon cancer cell line HT29.The results show that PEF-assisted extraction, enhancing the yield of bioactive compounds, with respect to untreated extracts, significantly promotes their antioxidant activity, which is correlated with an increased HT29 cells cytotoxicity. In addition, PEF extracts of brown rice substantially inhibit also gene expression and interleukin production in colon cancer cells, suggesting their exploitation as natural anti-inflammatory agents.The integration of PEF pretreatment in the solvent extraction process of bioactives from brown rice appears, therefore, as a promising practice to significantly enhance their biological activity.     

Competitive displacement of oil body surface proteins by Tween 80 – Effect on physical stability

A concentrated oil body cream, prepared from maize germ by aqueous extraction, was dispersed in water to obtain a natural 5% o/w emulsion. To improve the emulsion physical stability, the hydrophilic surfactant Tween 80 (polyoxyethylene sorbitan monooleate) was incorporated at levels ranging from 0.25 to 2%, and the increase of the oil body mean diameter and the volume of serum separated from the emulsion system, was followed with storage time. In addition, the amount and composition of oil body surface proteins competitively displaced by the surfactant was studied. The improvement in oil body stability against coalescence and creaming, resulting from Tween addition, is discussed in terms of the development at the oil body surface of an adsorbed film of a mixed nature, made up of surfactant- and phospholipid-rich domains, with the non-displaced surfactant protein molecules, mainly oleosins, remaining embedded in the latter.     

Soluble starch–based biodegradable and microporous microspheres as potential adsorbent for stabilization and controlled release of coix seed oil

Soluble starch–based biodegradable and microporous microspheres (SDM-Ms) were prepared by emulsion chemical cross-linking technique using trisodium trimetaphosphate (TSTP) as the cross-linker. The resultant amorphous SDM-Ms were excellently identified by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). The internal rupture and surface-controlled erosion were the predominant degradation mechanisms for SDM-Ms. The obtained SDM-Ms were applied to adsorb coix seed oil (CSO) by immersing method. The adsorption capacity of CSO within SDM-Ms was determined, namely 0.5238 g/g, and the thermal stability was shown higher than that of the free CSO. A burst release appeared in the second hour, followed by controlled release. Diffusion, degradation, and erosion mechanisms might coexist for the full release processes. The soluble starch (Ss) was demonstrated a promising biodegradable polymer for preparing the porous microspheres. Meanwhile, after being adsorbed into the SDM-Ms, the CSO can be powerfully applied in food and pharmaceutical industries.