Effect of ultrasound-assisted extraction on the structure and emulsifying properties of peanut protein isolate.

BACKGROUND: With an increasing demand for edible protein, research on new extraction methods is attracting more attention. The effects of such methods on functional properties are important. The present study aimed to evaluate the effect of ultrasound-assisted extraction on the extraction efficiency, structure, and the emulsifying properties of peanut protein isolate (PPI). RESULTS: Ultrasound-assisted extraction significantly improved extraction efficiency and shortened the processing time. The nanostructure, molecular weight distribution, and particle size of PPI were altered by ultrasound-assisted extraction. The emulsifying properties of the PPI from ultrasound-assisted extraction were significantly improved compared with alkaline extraction. Peanut protein isolate had lower molecular weight fractions, higher levels of hydrophobic amino acids, and the highest fluorescence intensity with ultrasound intensity, temperature, and time of 3.17 W cm-3 , 35 °C, and 30 min, respectively. These contributed to the higher emulsifying activity index and emulsifying stability index of the PPI emulsions. The uniform distribution of droplets and smaller particle size of the PPI emulsions was also observed. CONCLUSION: The results suggested that ultrasound can be used to induce the conformational changes to modify the interfacial association between protein-oil phases, thereby improving the emulsifying properties of peanut protein. © 2020 Society of Chemical Industry.

A Robust Carbon Nanotube and PVDF-HFP Nanofiber Composite Superwettability Membrane for High-Efficiency Emulsion Separation.

Oil or chemical purification is significant not only for industrial safety production but also because it conforms to the principle of sustainable development. In this paper, based on the synergistic concept of superwettability and nanopores sieve effect, a superoleophilic and under-oil superhydrophobic carbon nanotube/poly(vinylidene fluoride-co-hexafluoropropylene) nanofiber composite membrane is prepared via electrospinning, pressure-driven filtration, and chemical vapor modification. The as-prepared membrane with durable mechanical and chemical stabilities achieves separation efficiency higher than 99.9% and high flux up to 632.5 L m-2 h-1 bar-1 for different water-in-oil emulsions. This membrane is highly promising for the petroleum and chemical industries for both product quality improvement and green recycling manufacturing processes.

Effect of high pressure homogenization treatment on the rheological properties of citrus peel fiber/corn oil emulsion.

BACKGROUND: Citrus fiber is a main component in the peel of citrus and contains natural dietary fiber. It is often used as a functional additive to improve the texture or nutritional property of food. It is also widely used to reduce the content of absorbable fat in sausages and other meat products, and to improve food stability as an emulsifier. In this research, the dynamic rheological properties (linear and non-linear) of citrus peel fiber/corn oil (CF/CO) emulsion system under high pressure homogenization (HPH) treatment was investigated. RESULT: Rheological results illustrated HPH treatment significantly increased the apparent viscosity of the emulsion, reduced the activation energy of the emulsion and distinctly improved the viscoelasticity of the emulsion. Meanwhile, HPH treatment increased the linear viscoelastic region of the sample, and the behavior of the emulsion converted from strain thinning (without HPH treatment) to weak strain overshoot (with HPH treatment). Lissajous curves indicated the viscosity of the sample increased first and then decreased with strain increasing and the third harmonic contributed much more to the first harmonic compared with the fifth harmonic. Chebyshev stress decomposition revealed that, as strain increased, the samples with HPH treatment showed internal-cycle strain hardening behavior first, then turned to internal-cycle softening behavior. CONCLUSION: HPH treatment can significantly improve the processing performance of CF/CO emulsion as well as the stability against large periodic oscillations in food processing. © 2020 Society of Chemical Industry.

Production and investigation of the physico-chemical properties of MEL-A from glycerol and coconut water.

This work reports the production of MEL-A using coconut water as the carbon source. Proximate analysis of coconut water indicated the presence of nutrients necessary for growth of the organism and production of desired metabolite. The amount of MEL produced using coconut water was 3.85 g/L (± 0.35) with 74% of it being MEL-A when compared to 2.58 g/L (± 0.15) with 60% being MEL-A using glycerol, a conventional carbon source. MEL-A from coconut water consisted of 38.1% long-chain saturated fatty acids (C16:0 and C18:0) whereas with glycerol it was 9.6%. The critical micellar concentration of the biosurfactant from coconut water was 2.32 ± 0.21 µM when compared to 4.41 ± 0.25 µM from glycerol. The stability of O/W emulsion was reduced by 50% and 90% after incubation for 8 h in the case of MEL-A from coconut water and glycerol respectively when compared to synthetic surfactant, Tween-20. MEL-A from both the sources exhibited free radical scavenging activity (DPPH assay) in a dose-dependent manner wherein MEL-A from coconut water showed two fold higher activity than the other. The interaction of coconut water MEL-A with DPPC for drug encapsulation applications was also studied. The DSC measurements showed the differences in the interaction of drugs with DPPC/MEL-A liposome. The differences were also observed in the solubility of drugs after encapsulation with DPPC/MEL-A liposome.

Effects of high-speed shear homogenization on the emulsifying and structural properties of myofibrillar protein under low-fat conditions.

BACKGROUND: Emulsification is important for food quality and processing functionality. Most emulsification occurs under high-fat conditions that eventually cause health concerns. Protein emulsifiers also have drawbacks such as lower dispersity. This study considered the effects of different high-speed shear homogenization (HSH) speeds on the emulsifying and structural properties of myofibrillar proteins (MPs) under low-fat conditions. RESULTS: High-speed shear homogenization significantly increased the emulsifying activity and emulsifying stability of MPs at lower speeds (8000 to 14 500 rpm). The primary structure of MP was not altered significantly by HSH, whereas its secondary, tertiary, and quaternary structures were changed. Particle size decreased first and then increased significantly, and reached a minimum when the HSH speed was 14 500 rpm. The absolute zeta potential values increased significantly and the dendritic fibrous structure of sample was destroyed when the speed exceeded 14 500 rpm. High-speed shear homogenization (14 500 rpm) decreased the particle size and unfolded the protein, which improved the emulsifying properties of MPs. Excessive HSH speeds (20 500 rpm or higher) caused an aggregation of MP molecules, which was not conducive to improving their emulsifying properties. CONCLUSION: Optimal HSH speed was achieved at 14 500 rpm to modify MPs' emulsifying and structural properties under low-fatconditions. © 2019 Society of Chemical Industry.

Bioinspired Peptide-Coated Superhydrophilic Poly(vinylidene fluoride) Membrane for Oil/Water Emulsion Separation.

Polyvinylidene fluoride (PVDF) membranes are limited in the field of oil-in-water emulsion treatment because the intrinsic hydrophobicity of PVDF can cause serious membrane fouling. Here, a superhydrophilic PVDF membrane (PVDF@PDA-GSH) was fabricated using a facile, versatile, mussel-inspired method. The pristine PVDF membrane was coated with dopamine under mild alkaline conditions by a dip-coating method, followed by addition of glutathione (GSH) via a simple reaction. GSH was successfully coated onto the membrane surface and confirmed by X-ray photoelectron spectroscopy and energy dispersive X-ray spectrometry. Hierarchical surface structure and superhydrophilicity were examined by scanning electron microscopy and contact angle, respectively, giving the PVDF@PDA-GSH membrane excellent wettability and antifouling ability. The water flux of PVDF@PDA-GSH was several-fold higher than conventional filtration membranes, and the oil rejection ratio was nearly 99%. The PVDF@PDA-GSH membrane also showed favorable reusability because the flux recovery ratio (FRR) remained above 90% after five cycles. In general, these results indicated that this modification might provide a good method for the fabrication of superhydrophilic PVDF membranes with good prospects for water filtration applications.

Novel aqueous oil-in-water emulsions containing extracts of natural coniferous resins are strongly antimicrobial against enterobacteria, staphylococci and yeasts, as well as on bacterial biofilms.

AIMS: The aim of this study was to examine the antimicrobial properties of novel aqueous natural rapeseed oil/saline emulsions containing different soluble components of spruce resin. METHODS AND RESULTS: The composition of aqueous resin emulsions was analysed by GC-MS and their antimicrobial properties were studied with challenge tests and with turbidometric assays. The emulsions were strongly antimicrobial against common Gram-positive and Gram-negative bacteria (including MRSA) as well as common yeasts. Furthermore, they inhibited the biofilm formation and eradicated the microbial biofilms on tested microbes. Characteristic for the emulsions was the presence of oxidized resin acids. Other main components present in emulsions, such as lignans and coumaric acids, were not antimicrobial, when tested separately. CONCLUSIONS: The results indicated that the oxidized resin acids were the antimicrobial components in the emulsions. Also, there appears to be a stoichiometric relationship between the number of resin acid molecules and the number microbe cells in the antimicrobial action. SIGNIFICANCE AND IMPACT OF THE STUDY: The fact that these solutions do not contain abietic acid, which is the main allergenic compound in resins, suggests that these solutions would be suitable, well-tolerated antimicrobials for various medical applications. The aqueous formulation will also allow the expansion of the use of these emulsions in from medical applications to the food preservatives and disinfectants.

Effects of high-intensity ultrasound treatment on functional properties of plum (Pruni domesticae semen) seed protein isolate.

BACKGROUND: In order to improve the functional properties of plum seed protein isolate (PSPI), the effects of high-intensity ultrasound (20 kHz) at different levels of power output (200, 400 and 600 W) on the water/oil holding, solubility, emulsifying, foaming, gel, film formation capacity and hydrolysis degrees of PSPI were investigated. RESULTS: Compared with untreated PSPI, ultrasound treatment improved water holding capacity, solubility, emulsifying properties, foaming capacity of PSPI. The gel prepared from ultrasound treated PSPI showed the higher gel strength compared with untreated protein. The film prepared from ultrasound treated PSPI showed higher tensile strength, lower elongation and permeability, denser and more compact microstructure compared with untreated protein. Ultrasonic treatment also improved the accessibility of PSPI to the protease (Alcalase, Trypsin, Neutrase, Protamex, Papain and Flavourzyme). Furthermore, the ultrasonic treatment could induce a decrease in particle size and relative fluorescence intensity, an increase in surface hydrophobicity, and changes in secondary structure and microstructure of PSPI. CONCLUSION: The changes in structure analysis of PSPI indicated that ultrasound treatment could induce molecular unfolding of protein, which might be helpful for improving the functional properties and efficiency of enzymatic hydrolysis. © 2018 Society of Chemical Industry.

Optimization of mucilage extraction from chia seeds (Salvia hispanica L.) using response surface methodology.

BACKGROUND: Chia mucilage has potential application as a functional ingredient; advances on maximizing its extraction yield could represent a significant technological and economic impact for the food industry. Thus, first, the effect of mechanical agitation time (1-3 h) on the exudation of chia mucilage was analyzed. Then, response surface methodology was used to determine the optimal combination of the independent variables temperature (15-85 °C) and seed: water ratio (1: 12-1: 40.8 w/v) for the 2 h exudation that give maximum chia mucilage yield. Experiments were designed according to central composite rotatable design. RESULTS: A second-order polynomial model predicted the variation in extraction mucilage yield with the variables temperature and seed: water ratio. The optimal operating conditions were found to be temperature 85 °C and a seed: water ratio of 1: 31 (w/v), reaching an experimental extraction yield of 116 ± 0.21 g kg-1 (dry basis). The mucilage obtained exhibited good functional properties, mainly in terms of water-holding capacity, emulsifying activity, and emulsion stability. CONCLUSION: The results obtained show that temperature, seed: water ratio, and exudation time are important variables of the process that affect the extraction yield and the quality of the chia mucilage, determined according to its physicochemical and functional properties. © 2018 Society of Chemical Industry.

A multi-module microfluidic platform for continuous pre-concentration of water-soluble ions and separation of oil droplets from oil-in-water (O/W) emulsions using a DC-biased AC electrokinetic technique.

A novel continuous flow microfluidic platform specifically designed for environmental monitoring of O/W emulsions during an aftermath of oil spills is reported herein. Ionized polycyclic aromatic hydrocarbons which are toxic are readily released from crude oil to the surrounding water phase through the smaller oil droplets with enhanced surface area. Hence, a multi-module microfluidic device is fabricated to form ion enrichment zones in the water phase of O/W emulsions for the ease of detection and to separate micron-sized oil droplets from the O/W emulsions. Fluorescein ions in the water phase are used to simulate the presence of these toxic ions in the O/W emulsion. A DC-biased AC electric field is employed in both modules. In the first module, a nanoporous Nafion membrane is used for activating the concentration polarization effect on the fluorescein ions, resulting in the formation of stable ion enrichment zones in the water phase of the emulsion. A 35.6% amplification of the fluorescent signal is achieved in the ion enrichment zone; corresponding to 100% enrichment of the fluorescent dye concentration. In this module, the main inlet is split into two channels by using a Y-junction so that there are two outlets for the oil droplets. The second module located downstream of the first module consists of two oil droplet entrapment zones at two outlets. By switching on the appropriate electrodes, either one of the two oil droplet entrapment zones can be activated and the droplets can be blocked in the corresponding outlet.

Stability assessment of lycopene microemulsion prepared using tomato industrial waste against various processing conditions.

BACKGROUND: Green separation techniques are growing at a greater rate than solvent extraction as a result of the constant consumer drive to 'go natural'. Considering the increasing evidence of the health benefits of lycopene and massive tomato industrial waste, in the present study, lycopene was extracted from tomato industrial waste using microemulsion technique and its mean droplet size and size distribution was determined. Moreover, the effects of pasteurization, sterilization, freeze-thaw cycles and ultraviolet (UV) irradiation on the thermodynamic stability, turbidity and lycopene concentration of the lycopene microemulsion were monitored. RESULTS: Freeze-thaw cycles, pasteurization and short exposure to UV irradiation showed no or negligible influence on lycopene content and turbidity of the microemulsion. However, long exposure to UV (260 min) reduced the lycopene content and turbidity by 34% and 10%, respectively. HHST (higher-heat shorter-time) and sterilization also reduced lycopene content (25%) and increased turbidity (32%). CONCLUSION: The lycopene microemulsion showed satisfactory stability over a process where its monodispersity and nanosize could be of potential advantage to the food and related industries. Regarding the carcinogenicity of synthetic colourants, potential applications of the lycopene microemulsion include in soft drinks and minced meat, which would result in a better colour and well-documented health-promoting qualities. © 2017 Society of Chemical Industry.

Development of a nanoemulsion of Phyllanthus emblica L. branch extract.

For potential topical administration, we formulated a nanoemulsion containing phenolic constituents of Phyllanthus emblica branch extract. The nanoemulsion has high entrapment efficiency, small particle size, is stable, and can release its main chemical components. Branches of P. emblica were extracted with 50% ethanol (EPE) with 5.4% yield. HPLC analysis indicated several phenolic compounds, including gallic acid, vanillic acid, epigallocatechin (EGC), epigallocatechin gallate (EGCG) and ellagic acid. These were selected as chemical markers of EPE in the nanoemulsion development. The nanoemulsion was prepared by microemulsion techniques with hot high pressure homogenization. A ternary phase diagram was constructed to obtain the optimized nanoemulsion. The obtained transparent EPE nanoemulsion is composed of isopropyl myristate (0.6% w/w), Brij® 78 (0.35% w/w), and 0.15% (w/w) EPE. The optimized EPE nanoemulsion had a median particle size of 191.63 ± 4.07 nm with a narrow particle size distribution, a zeta potential of -10.19 ± 0.54 mV, high entrapment efficiency at 67.99 ± 0.87% and good stability at 4 °C after 90 d of storage. The release of active ingredients from the EPE nanoemulsion was slower than that of the EPE aqueous formulation. The loading ratios of the five phenolic compounds were high, with relative order of EGC > EGCG > vanillic acid > gallic acid > ellagic acid, resulting in slow release profiles of EGC and EGCG in the EPE nanoemulsion. In conclusion, the obtained EPE nanoemulsion has good characteristics for future clinical trials.

Microfluidic-assisted synthesis of hemispherical and discoidal chitosan microparticles at an oil/water interface.

This study reports a facile method for the synthesis of hemispherical and discoidal chitosan microparticles by a combination of microfluidic technology and gelation strategy at an oil/water interface. Utilizing microfluidic emulsification in a cross-junction channel, the formation of regular droplets was achieved. Following the ionic gelation procedure at the liquid-liquid interface of the gelling solution and oil solution in the reservoir pool, either hemispherical or discoidal chitosan microparticles were obtained. Special emphasis was put on the interface reaction of emulsion gelation parameters such as ionic crosslinkers, density modifiers, and surfactants, to tailor the morphologies of chitosan particles ranging from 160 to 750 µm. In addition, the proposed microfluidic device is capable of generating relatively uniform microparticles with a well-controllable shape and size. Being a simple, low-cost and high-throughput process is an added advantage. The synthesized hemispherical and discoidal chitosan microparticles can be applied to many applications in the pharmaceutical and biomedical arena.

Andiroba oil and nanoemulsion (Carapa guianensis Aublet) reduce lesion severity caused by the antineoplastic agent doxorubicin in mice.

Doxorubicin (DOX) is an anthracycline antibiotic used in the fight against many types of cancer. Although it is quite effective for this purpose, its clinical use is limited by its severe side effects, highlighting the relevance of efforts to identify substances that act to minimize these effects. In this work, we sought to verify the ability of andiroba oil (AO) and a nanoemulsion of andiroba oil (AN) to lessen the side effects of DOX. The animals were separated into 7 groups with 6 animals each: mice treated with AO (2000 mg/kg), AN (2000 mg/kg), the antineoplastic agent DOX (40 mg/kg), AO+DOX, AN+DOX and solvent controls was used of negative control (corn oil and nanoemulsion surfactant). AO and AN were administered for 14 consecutive days orally by gavage and on the 13th day, applied DOX by intraperitoneal route (i.p.), in order to evaluate the protective potential of andiroba. The animals were euthanized on the 15th day. Hematological, biochemical, histological, and immunohistochemical parameters were analyzed. Andiroba reduced several aspects of the severity of lesions caused by DOX, decreasing hematotoxicity and the severity of histological changes in the liver and kidneys, and reducing the frequency of apoptotic cell death. In many cases, AN showed greater efficacy than AO alone, reflecting the feasibility of using this nanotechnology to improve the pharmacokinetics of lipid compounds in the body. The study sheds new light on the therapeutic benefits of andiroba and suggests new ways for investigating how the quantity and quality of lipid compounds affect exposed organisms.

The formation, stability of DHA/EPA nanoemulsion prepared by emulsion phase inversion method and its application in apple juice.

This study prepared edible docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) nanoemulsion using EPI (emulsion phase inversion) method. The method for preparing DHA and EPA nanoemulsions is safe, convenient, low in energy consumption and can be used for food production. Factors affecting particle size and stability during preparation were investigated. Based on the optimal particle size combination, stability studies including particle size and residual rates of DHA and EPA at different temperature, pH and metal ions. The results showed that the nanoemulsion had good stability at low temperature storage, near neutral pH and in the absence of transition metal ions such as Fe3+, Cu2+, Al3+. The experiment initially studied the effect of nanoemulsion on apple juice beverage on the basic properties of juice itself. It was feasible in practical application of edible nanoemulsion.

Identification of emulsifier potato peptides by bioinformatics: application to omega-3 delivery emulsions and release from potato industry side streams.

In this work, we developed a novel approach combining bioinformatics, testing of functionality and bottom-up proteomics to obtain peptide emulsifiers from potato side-streams. This is a significant advancement in the process to obtain emulsifier peptides and it is applicable to any type of protein. Our results indicated that structure at the interface is the major determining factor of the emulsifying activity of peptide emulsifiers. Fish oil-in-water emulsions with high physical stability were stabilized with peptides to be predicted to have facial amphiphilicity: (i) peptides with predominantly α-helix conformation at the interface and having 18-29 amino acids, and (ii) peptides with predominantly ß-strand conformation at the interface and having 13-15 amino acids. In addition, high physically stable emulsions were obtained with peptides that were predicted to have axial hydrophobic/hydrophilic regions. Peptides containing the sequence FCLKVGV showed high in vitro antioxidant activity and led to emulsions with high oxidative stability. Peptide-level proteomics data and sequence analysis revealed the feasibility to obtain the potent emulsifier peptides found in this study (e.g. γ-1) by trypsin-based hydrolysis of different side streams in the potato industry.

Comparison of the performance of prepared pristine and TiO2 coated UF/NF membranes for two types of oil-in-water emulsion separation.

Polysulfone ultrafiltration (UF) and polypiperazine-amide nanofiltration (NF) membranes were first fabricated by phase inversion and interfacial polymerization, and then modified by the commonly used TiO2 on the membrane surface, respectively. Compared with the pristine UF and NF membranes, pure water flux decreased by 40.66% for modified UF membrane and 12.92% for modified NF membrane, while the contact angle of the modified membranes decreased from 66.5° to 35.3° for UF membrane and from 48.2° to37.7° for NF membrane. However, the membrane modified by TiO2 nanoparticles for both UF and NF membranes exhibited much better anti-fouling and separation performance for two types of oil-in-water emulsions with different droplet size (i.e., prepared oil-in-water emulsion with low salinity and oil produced water in Shengli oilfield, China). It was obvious that water flux of modified UF only slightly decreased and the stable water flux was 2.2 times and 15.6% higher than that of pristine membranes for the prepared oil-in-water emulsion and produced water, respectively. According to the five fouling models for UF, the TiO2 modified UF membrane could alleviate the fouling on membrane surface and greatly increase water flux by reducing the adsorption, deposition, blockage of membrane pores and formation of cake layer for two types of oil-in-water emulsion. For NF, water flux of the modified membrane increased by 66.1% and 22.8% for prepared oil-in-water emulsion and produced water, respectively. TiO2 coating effectively alleviated the oil adhesion and cake layer formation on the membrane surface.

Transdermal delivery enhancement of carvacrol from Origanum vulgare L. essential oil by microemulsion.

Carvacrol has been reported for analgesic and anti-inflammatory activity by cyclooxygenase inhibition but it could induce gastrointestinal toxicity because of its non-selective inhibition. Therefore, the present study aimed to develop transdermal microemulsion from Origanum vulgare essential oil to deliver carvacrol into and through the skin which would overwhelm the gastrointestinal problems. O. vulgare essential oil was extracted by hydrodistillation and its carvacrol content was determined using high performance liquid chromatography. Pseudoternary phase diagrams were constructed using water dilution method to investigate the suitable microemulsion components. Microemulsions were then characterized for external appearance, particle size, size distribution, zeta potential, electrical conductivity, refractive index, viscosity, transmittance, pH, and stability. Additionally, the irritation property of microemulsions were investigated by hen's egg on the chorioallantoic membrane assay. The release profile, percutaneous absorption, and skin retention were investigated using dialysis bag and Franz diffusion cell, respectively. The interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were investigated using the enzyme-linked immunosorbent assay. The results remarked that carvacrol was a major component of O. vulgare essential oil with high concentration of 83.7%. The most suitable microemulsion (ME 1), composing of 5% w/w O. vulgare essential oil, 25%w/w Tween 60, 25%w/w butylene glycol, and 45%w/w deionized water, had the smallest internal droplet size (179.5 ± 27.9 nm), the narrowest polydispersity index (0.30 ± 0.07), the highest transmittance (93.13 ± 0.04%), and Newtonian flow behavior with low viscosity of 0.30 ± 0.07 Pas. ME 1 could reduce the irritation effect of O. vulgare essential oil since ME 1 (IS = 3.1 ± 0.10) exhibited significantly lower irritation effect than its blank formulation (IS = 4.8 ± 0.02) and O. vulgare oil solution (IS = 5.0 ± 0.01) (p < 0.05). Furthermore, ME 1 sustain released carvacrol from the formulation, remarkedly deliver more carvacrol through the skin layer (2.6 ± 2.2%) and significantly retained carvacrol in the skin layer (2.60 ± 1.25%). Additionally, ME 1 significantly enhanced IL-6 inhibition of O. vulgaris oil and carvacrol (p < 0.05). Therefore, O. vulgaris oil microemulsion was suggested to be used for the transdermal delivery and anti-inflammatory activities enhancement of carvacrol.

Quantitative approach to ultrasonic emulsion separation.

Ultrasound of 2 MHz was irradiated to the emulsion prepared from canola oil and water and flocculation of the oil droplets occurred immediately. By putting the emulsion sample in a thin glass cell and setting it in bath type irradiation equipment, the progress of the separation was quantitatively monitored with the optical absorbance. The use of the cell enables visual observation of the behavior of oil droplets. Pictures show the formation of flocks of the dispersed phase and the appearance of checkered pattern consisting of flocks at a regular interval. The observation indicates that the action of radiation forces on oil droplets, which causes the flocculation. The flocks started to rise after stopping irradiation with holding their shape. The rising rate of the flocks was significantly greater than that of oil droplets in the original emulsion. Ultrasonic irradiation caused a rapid decrease in the absorbance, which expresses a progress of the separation. Effects of two major operation parameters, power and time on the separation degree were examined. The degree improved with increasing power input and irradiation time. The dataset was arranged in a plot of normalized separation degree against the input energy. The plot suggests that effective separation was attained with a lower power input and a longer irradiation time. The plot provides a guide for setting condition for the separation.

Preparation and some functional properties of rice bran protein concentrate at different degree of hydrolysis using bromelain and alkaline extraction.

Rice bran protein was extracted by using defatted rice bran and water at 1:6 (w/w) and 6% of bromelain at pH 9.0, 50 degrees C, 500 rpm for 15 and 30 mins. The degree of hydrolysis (DH) of rice bran protein extract (RBPE) was 19 and 36.5%, respectively, and their nitrogen solubility was higher than the controls. Rice bran protein concentrate (RBPC) was prepared by spray drying. Emulsion activity of RBPC produced from 19% DH RBPE was increased while emulsion stability index was not significantly different from the control. Foam capacity and rehydration ability of RBPC were greater than the control.