FUZZY CLUSTERING MODELING AND EVALUATION OF SURFACE INTERACTIONS AND EMULSIONS OF SELECTED WHEAT PROTEIN COMBINED TO IOTA-CARRAGEENAN AND GUM ARABIC SOLUTIONS

Gums and proteins are valuable ingredients with a wide spectrum of applications. Surface properties (surface tension, interfacial tension, emulsion activity index [EAI] and emulsion stability index [ESI]) of 4% deamidated wheat protein (DWP) in a combination with iota-carrageenan (IC) (0.05, 0.1 and 0.5%) or gum arabic (GA) (0.5, 1 and 5%) were investigated. The results showed that the addition of IC to 4% DWP significantly increased the surface tension, interfacial tension, EAI and ESI, whereas the addition of GA to 4% DWP significantly increased the surface tension and decreased the interfacial tension and EAI (except at 5% of GA). In addition, a fuzzy-based clustering model was used to predict the surface properties of the DWP. The fuzzy model achieved accuracies of (97%, 90%, 97% and 75%) for predicting (EAI, ESI, surface tension and interfacial tension), respectively. This approach can be applied to predict many other parameters and properties in the food industry.

PRACTICAL APPLICATIONS

The surface properties (surface tension, interfacial tension, emulsion activity index and emulsion stability index) of wheat protein (DWP) in combination with iota-carrageenan or gum arabic were investigated. In addition, subtractive clustering-based fuzzy models for predicting the surface properties of DWP was constructed. This modeling can be used as an indicator of usefulness of fuzzy clustering in such a system which directly can be used as a tool by the food processors to produce a high quality beverage product.     

DETECTION AND DISCRIMINATION OF ENTEROBACTER SAKAZAKII (CRONOBACTER SPP.) BY MID-INFRARED SPECTROSCOPY AND MULTIVARIATE STATISTICAL ANALYSES

Enterobacter sakazakii can cause rare but life-threatening diseases such as meningitis in infants and neonates. Fourier transform infrared (FT-IR) spectroscopy was used to detect and discriminate between eight E. sakazakii strains, two Enterobacter cloacae strains, three Escherichia coli strains and two Klebsiella pneumoniae strains. FT-IR vibrational combination bands reflect subtle compositional differences in the cell membranes of E. sakazakii strains, especially in the region between 1,200 and 900 cm ^{− 1} which contains absorption bands from carbohydrates. Two multivariate statistical analyses including principal component analysis (PCA) and soft independent modeling of class analogy (SIMCA) were used for data analysis. E. sakazakii strains were clearly distinguishable from the other strains by PCA. Based upon SIMCA analysis, 90% of E. sakazakii, 88% of E. cloacae, 91% of E. coli and 91% of K. pneumoniae samples were correctly classified, suggesting that this technique could be used to detect E. sakazakii strains rapidly and accurately.

PRACTICAL APPLICATIONS

Fourier transform infrared (FT-IR) coupled with multivariate statistical analyses can be used to detect, discriminate and identify Enterobacter sakazakii strains that have been implicated in food safety incidents caused by contaminated infant formula. Compared with traditional microbiological plating methods, this new approach of using FT-IR could be an alternative means for rapid and accurate detection of bacterial samples that are important in agricultural, food and medical areas.     

CHARACTERIZATION OF SALMON (ONCORHYNCHUS KETA) AND STURGEON (ACIPENSER TRANSMONTANUS) CAVIAR PROTEINS

The solubility of protein components in salmon (Oncorhynchus keta) and sturgeon (Acipenser transmontanus) caviar in distilled water, 5% (w/v) NaCl, 70% (v/v) ethanol at 65C, and 0.2% (w/v) NaOH was determined. The salt soluble proteins were the predominant fraction and constituted 84.2% of the recovered protein in salmon and 86.1% in sturgeon samples. The two most prominent protein fractions (12.5% sodium dodecyl sulfate‐polyacrylamide gel electrophoresis) for sturgeon caviar are most likely vitellin (96 kDa) and ovomucoid or phosvitin (28 kDa). For salmon roe, small proteins, possibly lysozyme or phosvitin (10 kDa), are also present.     

Seismic retrofitting of severely damaged RC connections made with recycled concrete using CFRP sheets

An experimental and numerical program is carried out in this research to investigate the influence of CFRP sheets on the cyclic behavior of unconfined connections made with recycled concrete. Cement is partially replaced by silica fume, iron filling and pulverised fuel ash using two different percentages: 15% and 20%. Each specimen is partially loaded at the first stage and then specimens are repaired using CFRP sheets. The repaired specimens are then laterally loaded until failure. In addition, a finite element model is built in ABAQUS and verified using the experimental results. The experimental results have shown that the repaired specimens have regained almost double the capacity of the un-repaired specimens and hence the adopted repair configuration is recommended for retrofitting seismically vulnerable RC connections. Increasing cement replacement percentage by silica fume, fuel ash or iron filling from 15% to 20% has reduced joint carrying capacity and weakened the joint. It is recommended using 15% pulverised fuel ash or silica fume as cement partial replacement to enhance the strength and ultimate drift of beam-column joints under cyclic loading. Iron filling concrete is also recommended but the enhancement is relatively less than that found with pulverised fuel ash concrete and silica fume concrete.     

Capillary Flow of Power-Law Non-Newtonian Liquids in Circular Tubes

The penetration rate of power-law non-Newtonian liquids in a circular tube driven by the capillary pressure is derived. The dimensionless fractional height of liquid in the tube relative to the equilibrium height, χ = h(t)/h(∞), is calculated as a function of an appropriately chosen dimensionless time, permitting expression of the height-time dependence as a function of the reciprocal of the exponent in the power-law model, s = 1/n. It is found that the rate of penetration and, therefore, also withdrawal of liquid is dramatically retarded as the liquid becomes more strongly shear-thinning, i.e., as n becomes small relative to unity.     

Deconvolution of fractional brownian motion

We show that a fractional Brownian motion with H'∈(0,1) can be represented as an explicit transformation of a fractional Brownian motion with index H ∈(0,1). In particular, when H'=½, we obtain a deconvolution formula (or autoregressive representation) for fractional Brownian motion. We work both in the `time domain' and the `spectral domain' and contrast the advantages of one domain over the other.     

SURFACE TENSION OF POLAR LIQUIDS AND MIXTURES

The simple principle of corresponding states for surface tension, has been generalized to include polar compounds (including those exhibiting hydrogen bond) and their mixtures, by introducing an additional parameter to characterize molecular polarity. In addition the statistical tool of factor analysis has been used to correlate this parameter. For mixtures a binary interaction parameter is also needed, which has also been correlated with easily available properties. Good agreement has been obtained for a wide range of pure liquids and mixtures.