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Background: Pre-eclampsia (PE) affects 2% to 5% of all pregnancies and is a major cause of maternal and perinatal morbidity and mortality worldwide. Since PE has complex pathogenesis and treatment is still not found, effective methods for prediction and prevention of PE are still actively searched.

This research was undertaken to evaluate the influence of the extrusion process on the sorption behavior of deproteinized sunflower meal (DSM). A patterned food extrudate (PFE), prepared from a mixture of DSM and corn grits (1:1), was obtained, and the equilibrium isotherms of both products (DSM and PFE) were determined at three temperatures (20 °C, 30 °C, and 40 °C) by the static gravimetric method. The comparison of the sorption behavior of the products showed that extrusion decreased the equilibrium moisture content and the monolayer moisture, while the hysteresis effect was significantly raised in size and span. The experimental sorption isotherms were fitted by five modified models including the temperature effect: Chung–Pfost, Halsey, Oswin, Henderson, and GAB. The modified models of Oswin were established to be suitable to describe the equilibrium sorption isotherms in the temperature range from 20 °C to 40 °C. The net isosteric heat of sorption of DSM and PFE decreases consistently with the increase in moisture content. Extrusion reduces the bond energy between the solid matrix and the water molecules. The ranges of moisture content and relative humidities in the temperature interval studied, appropriate for long-term storage of DSM and PFE, were predicted. [ABSTRACT FROM AUTHOR]

Rapeseed meal is a by-product of oil extraction which is generated in substantial amounts worldwide. The ethanol-wash solute (EWS) was prepared as a waste of protein isolate generation from industrial rapeseed meal after a 4-time treatment with a 75% aqueous ethanol solution. The ethanol-wash liquids were collected, vacuum concentrated and lyophilisied to prepare EWS. The aim of this study was to evaluate the influence of three concentration levels (0.1, 0.3 and 0.5%) and temperature (20, 30, 40 and 50°C) on surface tension and EWS dissolution behaviour by using conductivity measurement. The EWS solubility in water was dependent on both concentration and temperature. For the all three concentrations, maximum conductivity was achieved at 50°C. For the lowest EWS concentration studied (0.1%), the rate constant of dissolution increased with the increase of the temperature reaching 0.1838 1/s at 50°C. The rate constants of the dissolution of 0.3 and 0.5% EWS though increased with the increase of temperature to 40°C followed by a sharp drop at 50°C. The addition of EWS decreased the surface tension of pure water at all three concentrations. The most profound effect was observed at 50°C where the surface tension of water (67.14 mN/m) was reduced 2-fold (33.92 mN/m) after adding 0.5% EWS. Acquired information is valuable by concerning formulation, fabrication process or final quality of products where the EWS is added as a supplement. [ABSTRACT FROM AUTHOR]

Rapeseed meal was treated with 70% ethanol to reduce anti-nutrient compounds, and used in the preparation of a protein isolate. The ethanol-treated rapeseed meal protein isolate (ERPI) was produced by alkaline extraction of proteins (pH 12) followed by isoelectric precipitation at pH 4.5. The aim of the present work was to evaluate the potential of ERPI as an emulsifying agent in corn and olive oil-in-water emulsions under slightly acidic conditions (pH 6). A total of nine emulsions for each type of oil were prepared to assess the significant effect of two variables, oil (5, 10, and 15% w/w) and ERPI protein concentrations (0.25, 0.5, and 1.0% w/w), on emulsion stability. The initial stability was evaluated by Gibbs free energy (ΔG) and lipid particle size distribution, while the dynamics of emulsion stability was investigated along 7 d by turbidity measurement. The increase in concentration of both types of oil positively influenced initial stability of the emulsions as indicated by ΔG. At each oil concentration, the three ERPI supplementation levels resulted in significant differences in ΔG. While in all olive oil-in-water emulsions, the highest initial stability was achieved by the addition of 0.25% ERPI; and in corn oil-in-water emulsions, lower ΔG values were achieved by supplementing either with 0.5 or 1.0% ERPI. With a few exceptions, there was an agreement between Gibbs free energy and microstructural characteristics of the emulsions. With a reduction in turbidity not higher than 30% at day 7, all corn oil-in-water emulsions supplemented with 0.5% ERPI demonstrated a better stability than the emulsions prepared with olive oil. [ABSTRACT FROM AUTHOR]

Rapeseed meal is a by-product of oil production with relatively high antinutrient content which limits its application in both feed and food industries. A two-step procedure, including two-level full factorial and central composite designs, was used to assess the influence of five factors, namely pH (6 and 12), temperature (20 and 40°C), NaCl concentration (0 and 7.5%), rapeseed meal concentration (2.5 and 5%), and extraction longevity (15 and 60 min), on protein extraction from industrial rapeseed meal subjected to ethanol-assisted reduction of antinutrients. Data demonstrated that pH and its interaction with NaCl influenced protein extractability the most. While still significant, individual effects of NaCl, extraction longevity, temperature and its interaction with pH had a less significant effect on protein yield. Overall, higher protein yields were obtained in response to combining high pH values with low NaCl concentrations, and high pH values with high temperatures. The highest protein yield (59.56 ± 1.29%) was achieved after extraction of 5% ethanol-treated rapeseed meal at pH 12 with no NaCl addition, at 40°C and extraction longevity of 60 min. A second-order polynomial model for protein yield prediction was generated. The adequacy of the model was verified by coefficient of determination and residual analyses. A high correlation between experimentally obtained and predicted protein yields (R2 = 0.95) was established. Since extraction conditions are strong determinants of protein characteristics, the predictive model generated in the present work is useful for the selection of factor combinations, which allows for the achievement of optimal protein yield of a product with desired techno-functional properties. [ABSTRACT FROM AUTHOR]

Rapeseed meal is produced in large quantities as a by-product of vegetable oil production. To enhance the utility and profitability of the rapeseed meal, it was treated with ethanol and used for concomitant preparation of two protein-rich ingredients, namely protein isolate (PI) and acid soluble protein (ASP). Their functional properties were evaluated in response to two boundary concentrations of NaCl (0.03 and 0.25 mol/L) in a wide pH range (2 to 10). The PI exhibited the lowest protein solubility at isolectric point (pH 4.5) which increased both at lower and higher pH. In contrast, ASP exhibited high protein solubility (>70%) which was negligibly influenced by pH. The addition of 0.03 mol/L NaCl increased its protein solubility to almost 100% at acidic pH. The water holding capacity of PI was positively influenced by the addition of 0.25 mol/L NaCl. The ASP did not exhibit any capacity to hold water but demonstrated higher ability to absorb oil compared to the PI. Both ingredients exhibited different thermal stability in response to salt addition at pH 7 and 8. PI and ASP exhibited completely different pattern of emulsion stability as influenced by pH. While the stability of PI emulsions was close to 100% and only negligibly affected by pH, the ASP emulsion stability significantly varied in response to pH variation. The concomitant production of PI and ASP resulted in products with distinctive techno-functional properties, which makes them suitable for different applications as additives in the formulation of new food products. [ABSTRACT FROM AUTHOR]

The utilization of industrial sunflower meal to produce protein-rich products for the food industry is an alternative approach for bett er and more efficient use of this agricultural by-product. Sunflower meal proteins possess specific functional properties, which however need improvement to broaden their potential as supplements for delivering high-quality products for human nutrition. The aim of the study is to evaluate the combined influence of low-degree pepsin hydrolysis and transglutaminase (TG) modification on industrial sunflower meal protein isolate functionality at pH=2 to 10. Three TG-modified pepsin hydrolysates with the degree of hydrolysis of 0.48, 0.71 and 1.72 % were produced and named TG-PH1, TG-PH2 and TG-PH3, respectively. All three TG-modified pepsin hydrolysates exhibited improved solubility at pH between 3.5 and 5.5 as the highest was observed of TG-PH3 at protein isoelectric point (pI=4.5). Sunflower meal protein isolate and TG-modified sunflower meal protein isolate had greater solubility than the three TG-modified hydrolysates at pH<3 and >7. Significant improvement of foam making capacity (p<0.05) was achieved with all three TG-modified pepsin hydrolysates in the entire pH area studied. Pepsin hydrolysis of the protein isolate with the three degrees of hydrolysis did not improve foam stability. Improved thermal stability was observed with TG-PH3 up to 80 °C compared to the protein isolate (pH=7). At 90 °C, TG modification of the protein isolate alone resulted in the highest thermal stability. Pepsin hydrolysis followed by a treatment with TG could be used to produce sunflower protein isolates with improved solubility, foam making capacity and thermal stability for use in the food industry. [ABSTRACT FROM AUTHOR]

Protein-rich products, prepared from industrial rapeseed meal, have the potential for versatile applications in the food, feed, and nutraceutical industries. The aim of study was to characterize the biochemical composition of two protein-rich products obtained from industrially produced rapeseed meal. Protein isolate (PI) and acid soluble protein (ASP) were prepared by alkaline extraction (pH 12.0) followed by isoelectric precipitation (pH 4.5). Biochemical analyses revealed that PI contained a high protein amount (86.9%), while ASP had 28.8% protein and a relatively high level of non- protein compounds including ash (20.6%) and fiber (30.0%). Results showed that neither protein products contained glucosinolates. They were rich in microelements; the most abundant were Cu (64.3 mg kg-1) and Fe (133 mg kg-1) in PI and Mn (39.7 mg kg-1) and Zn (84.2 mg kg-1) in ASP. PI and ASP were also a good source of Se (1.1 mg kg-1 and 0.9 mg kg-1, respectively). Lysine was the most abundant essential amino acid in PI with amino acid score of 100.7% followed by leucine (98.3%) and valine (95.8%). Both protein products were mainly composed of low molecular weight fractions (5 to 33 kDa), but in different ratio. The PI contained two fractions with molecular weights 53 and 235 kDa which were not found in ASP. In conclusion, PI and ASP exhibited different biochemical characteristics which make them suitable for different applications. [ABSTRACT FROM AUTHOR]