Papers by Keyword: Functional Property

Abstract: The review on effect of a high strain rate on the properties of TiNi-shape memory alloys is presented. The study of thermo-mechanical and functional properties of SMA after high strain rate loading was carried out. The object of study was an equiatomic TiNi shape memory alloy. The samples were tensioned at a strain rate of about 10³ s^-1 at various temperatures in martensitic, austenitic, and two-phase state, using the Split Hopkinson Pressure Bar technique. Two-way shape memory effects were investigated. Two-way shape memory after high strain rate loading was less than after the quasi-static one for all cases, except for straining in martensitic state.

Abstract: Binary TiNi alloys containing 50.0 at.% Ni and 50.7 at.% Ni were tested under bending. Shape memory effect (SME) and two-way SME (TWSME) parameters were measured. Low-temperature thermomechanical treatment (LTMT) by drawing with true strain e ≈ 0.6 and post-deformation annealing (PDA) was performed in the temperature range 300600С for 0.3  1 hr permitted obtaining different types of initial austenite structure. The wires with 0.3 and 0.45 mm in diameter were studied. The curves of element distribution through the surface layer were graphed. The SME training procedure was carried out in bending with the constrained strain 0.7 and 8 %. Thickness, structure and element composition of the oxide film strongly depend on PDA regimes. In all cases titanium quantity in the boundary layer correlates with the oxygen quantity, diffused from the surface. Evidently, it is caused by their chemical reaction and oxide formation. Nickel atoms remain in uncombined state, and their migration is directed from the surface deep into the sample. LTMT permits decreasing the film thickness more than by 10 times. Surface state strongly affects all studied parameters: characteristic temperatures, recovery strain and TWSME value. Increasing of wire diameter from 0.3 to 0.45 mm leads to significant changes of studied parameters. Forecasting of said influence is difficult because of its ambiguity. Therefore, the oxide film must be eliminated by etching in order to obtain the reliable results

Abstract: The functional properties of corn steeping water protein concentrated (CSWPC) were investigated, and compared with soybean protein isolated (SPI). The results showed that the emulsifying capacity and viscosity of CSWPC were slightly lower than that of SPI, but the emulsifying stability, foaming property, foaming stability, gelatinization and oil absorption of CSWPC were better than that of SPI. The CSWPC showed better emulsifying capacity and stability at protein concentration of 1-3%、NaCl concentration of 0.15-0.3mol/L under alkali environment. The gelatinization of CSWPC got better with the increase of concentration of CSWPC. The foaming property was increased with the increase of sucrose concentration, but the foaming stability was decreased with the increase of sucrose concentration. The oil absorption capacity was increased slightly with the increase of temperature.

Abstract: Antioxidative activity and functional properties of hydrolysates prepared from defatted camellia seed meal(DCSM), using trypsin, with a degree of hydrolysis(DH) of 21.69% were determined. At this DH, the hydrolysates show the highest hydroxyl and superoxide anion radical scavenging activity (over 69.15 % and 78.22%, respectively). The functionalities of hydrolysates such as solubility, water-holding capacity,emulsifying activity, foaming capacity and foaming stability are remarkably improved at all test pH range. These results indicate that the DCSM hydrolysised by trypsin to produce hydrolysates with desirable antioxidative activity and functional properties.

Abstract: Hydrolysated peptides from kinds of proteins have been applied as natural ingredients in food industry, mainly due to their good functional properties. However, the fate of them under different processing conditions is rarely understood. In our study, changes of functional properties in porcine plasma protein hydrolysates (PPH) were evaluated in a free hydroxyl radical-mediated oxidation system. PPH was obtained by hydrolyzing porcine plasma protein with Alcalase for 5 h at pH 8.0, 55°C. When exposed to free radical-mediated oxidation, functional properties of PPH improved dramatically with growing oxidant concentrations and reaction time, especially at 20°C. Solubility, foaming capacity and emulsification of PPH increased significantly (P < 0.05) during early stage of oxidation, with solubility increasing from 83.1% (non-oxidized PPH) to 97.4%(20°C, 10mM H₂O_{Subscript text}2, 5 h), emulsifying activity index and foaming capacity rising form 1.24m2/g to 2.73 m2/g, and 144% to183%, respectively. Stability for emulsifying and foaming were also found to be reinforced. The improvements in functional properties of PPH helped to play theoretical basis for applying the peptides in food systems.

Abstract: Protein hydrolysates from Tuna frame (TFPH) and Pollock frame (PFPH) were prepared by papain, respectively.The yield, the basic composition content, the antioxidant activity and functional properties (solubility, emulsifying and foaming ability) and the degree of hydrolysis of the protein hydrolysates were evaluated. Results suggest that solubility, antioxidant activity of protein hydrolysate from Pollock frame are better than that of tuna frame, but the yield is lower than that of tuna frame.

Abstract: Extraction method by which auricularia auricula was treated affects the phytochemical composition and properties of the fibre-rich powders. Factor such as the solvent used was studied, and the significance of such changes was largely dependent on the alkali liquor. Among the auricularia auricula phytochemicals, crude protein, glucosamine, fat and carbohydrate were quantified. Crude protein ranged from 9.98% to 4.40%, and fat ranged from 2.51% to 3.71%, and carbohydrate ranged from 88.21% to91.66%, the content being affected by the solvent, in some cases. Dietary fibre (DF) from alkali liquor treatments had significantly higher amounts of glucosamine than samples extracted by water. The water-holding capacity (WHC), water retention capacity (WRC) and oil-binding capacity (OBC) of fibres from alkali liquor treatments were decreased by 51.4, 48.1, and-3.8%, respectively. The cation exchange capacities (CEC) was significantly lower from alkali liquor treatments, and CEC was only 0.02 meq/g fibres that decreased by 95.4%. The results showed that, in order to preserve the DF quality, the extraction solvent should be important. DF functional properties might be degraded or modified.

Abstract: The effects of frozen storage time on the functional properties of frozen wheat gluten were evaluated. The frozen wheat gluten was subjected to frozen storage in refrigerator at－18°C for 0–120days. The samples were obtained by the process of freeze-drying. The main functional properties of frozen wheat gluten were determined to confirm the effects of frozen storage time on functional properties of frozen wheat gluten. Results showed that solubility, water-holding capacity, emulsifying capacity, foamability and foam stability of frozen wheat gluten decreased and that oil-holding capacity, emulsion stability of frozen wheat gluten were improved with prolonged frozen storage time.

Abstract: The whey protein has a highly nutritional value but poor functional properties. Ultra-high pressure (UHP) is a new technology for food processing. It dose not cause environmental pollution and could maintain food nutrition as much as possible. The effects of applied pressure and treatment time on functional properties and conformation changes of whey protein isolated (WPI) treated by UHP were studied in present paper. The results indicated that WPI treated by UHP showed reduced solubility, foaming and emulsifying property with the increasing of applied pressure and prolonging of treatment time. For WPI treated at 400MPa for 15min, the 1-anilinonaphthalene-8-sulphonate (ANS) studies showed the increasing fluorescence regions when the applied pressure increased. The most fluorescence regions were exposed to aqueous solution for WPI treated at 400MPa for 5min, and degree of exposure reduced when treatment time was prolonged. With the increasing of applied pressure and prolonging of treatment time, the amino acid residues having ultraviolet absorbance showed the same change as hydrophobic group.

Abstract: The nutritional value and functional properties of corn germ protein hydrolysates was investigated. The amino acid profile of hydrolysates showed that there was an increase in the content of essential amino acids, His, Arg, Ile, Val and a decrease in Lys, Phe, Met when compared with the starting material. The low degree of hydrolysis (5.9%, 10.4%) improved the solubility at acid pH, WHC, OHC of corn germ protein isolates, but samples of high degree of hydrolysis (14.1%) was not significantly increased in WHC and OHC.