Optimization of the basic formulation of a traditional baked cassava cake using response surface methodology

The optimum formulation for production of a Malaysian traditional baked cassava cake was determined using response surface methodology (RSM). Effects of amount of ingredients such as sugar (10-30%) and coconut milk (15-35%) on the textural characteristics (hardness and chewiness) and sensory qualities (colour, firmness, cassava flavour and overall acceptability) of cakes were investigated. Significant regression models which explained the effects of different percentages of sugar and coconut milk on all response variables were determined. The coefficients of determination, R² of all the response variables were higher than 0.8. Based on the response surface and superimposed plots, the basic formulation for production of Malaysian traditional baked cassava cake with desired sensory quality was obtained by incorporating with 25% of sugar and 20% of coconut milk.     

Canine-Specific PCR Assay Targeting Cytochrome b Gene for the Detection of Dog Meat Adulteration in Commercial Frankfurters

This report described a cytochrome b (cytb)-based polymerase chain reaction (PCR) assay for the detection of canine tissues in commercial frankfurters. Discriminating detection of canine derivatives in processed food products has important application in halal authentication as well as in health, religions, and fare trades. The assay based on a pair of canine-specific primers that targeted a 100 bp region of canine mithochondrial-cytb gene which is present in multiple copies and highly conserved within the same species. The specificity of the assay was tested against dog and eight most common animal meat species as well as five plant species commonly found in frankfurter formulation. The stability and specificity of the assay were verified under different thermal processing conditions under pure and complex matrices. Three commercial brands of chicken and beef frankfurters were tested in triplicate, and specific PCR products were obtained only from deliberately contaminated formulations. The detection limit of the assay was 0.1 % (0.02 ng DNA) of canine meat spiked with other meats in a typical frankfurter formulation. Shorter amplicon length, superior stability, and higher sensitivity of the assay suggested its potential application in the screening of canine-origin biomaterials in processed food products.     

Detection of differential levels of proteins in the urine of patients with endometrial cancer: analysis using two-dimensional gel electrophoresis and o-glycan binding lectin

Cancers can cause some proteins to be aberrantly excreted or released in the urine, which can be used as biomarkers. To screen for potential biomarkers for endometrial cancer (ECa), the urinary proteins from patients who were newly diagnosed with early stage ECa and untreated controls were separated using two-dimensional gel electrophoresis (2-DE) and followed by image analysis. The altered levels of zinc alpha-2 glycoprotein, alpha 1-acid glycoprotein, and CD59 were detected in the patients compared to the controls. In addition, the urine of the ECa patients was also found to contain relatively lower levels of a fragment of nebulin when the 2-DE separated urinary proteins were probed using champedak galactose binding (CGB) lectin. The different levels of the nebulin fragment were further validated by subjecting the urinary protein samples to CGB lectin affinity chromatography and analysis of the bound fractions by LC-MS/MS. Our data is suggestive of the potential use of the differentially expressed urinary proteins as biomarkers for ECa although this requires further extensive validation on clinically representative populations.     

Salivary proteins associated with periodontitis in patients with type 2 diabetes mellitus

The objective of this study was to investigate the salivary proteins that are associated with periodontitis in patients with Type 2 diabetes mellitus (T2DM). Volunteers for the study were patients from the Diabetic Unit, University of Malaya Medical Centre, whose periodontal status was determined. The diabetic volunteers were divided into two groups, i.e., patients with periodontitis and those who were periodontally healthy. Saliva samples were collected and treated with 10% TCA/acetone/20 mM DTT to precipitate the proteins, which were then separated using two-dimensional polyacrylamide gel electrophoresis. Gel images were scanned using the GS-800(TM) Calibrated Densitometer. The protein spots were analyzed and expressed in percentage volumes. The percentage volume of each protein spot was subjected to Mann-Whitney statistical analysis using SPSS software and false discovery rate correction. When the expression of the salivary proteins was compared between the T2DM patients with periodontitis with those who were periodontally healthy, seven proteins, including polymeric immunoglobulin receptor, plastin-2, actin related protein 3, leukocyte elastase inhibitor, carbonic anhydrases 6, immunoglobulin J and interleukin-1 receptor antagonist, were found to be differentially expressed (p < 0.01304). This implies that the proteins may have the potential to be used as biomarkers for the prediction of T2DM patients who may be prone to periodontitis.     

Effects of a magnetic field on chaotic convection in fluid layer heated from below

Features of nonlinear dynamics of thermal convection in an electrically conducting fluid layer heated from below and cooled from above subjected to a constant magnetic field are studied theoretically. The Galerkin truncated approximation is employed to derive a low dimensional Lorenz-like model. Numerical analysis was performed to examine the influence of magnetic field on the phase space trajectory of various chaotic regimes. The result indicates that it is possible to suppress or enhance the chaotic convection.     

KINEMATIC VISCOSITY-TEMPERATURE CORRELATION FOR UNDEFINED PETROLEUM FRACTION OF A WIDE BOILING RANGE

A new correlation was developed to predict the effect of temperature on Kinematic Viscosity of petroleum fractions of all boiling ranges including 455^-°C. This correlation covers a wide boiling ranges of petroleum fractions. This correlation has been developed to represent the data for a wide range of temperature from 30 to 200°C. The correlation is based on experimental kinematic viscosity data for twenty TBP fractions of Arab heavy, Arab medium and Arab light and Arab extra-light crude oils. The proposed correlation has been found to fit all the experimental data consisting of 248 measurements of the kinematic viscosity with an over all average absolute deviation of 7.2% compared to 9.1% given by Amin (1994) et al. method.     

The composition of the extractives from unaffected and heartrot affected heartwood of Acacia mangium Willd

has been studied by a successive extraction of the wood with a series of solvents with increasing polarity, followed by GC, GC/MS and DC studies of the fractions obtained. The study of the extractives of sound and affected wood with respect to yield and composition cannot explain the influence of the heartrot fungi on wood components in detail. Differences mainly have been found in the more polar fractions (acetone/water and ethanol/water, respectively). The content of lipophilic extractive constituents is with about 0.6–0.7% rather low and does not differ between sound and affected heartwood. The composition of the lipophilic extractives is not very different either.     

Cleavage Strength of Steel/Composite Joints

This paper presents the experimental results of an on-going study to examine cleavage strength, particularly at the interface regions of epoxy adhesive with steel and glass reinforced epoxy (GRE) composite. The adhesion is characterised by mechanical testing of cleavage specimens. A standard specimen was modified to allow testing of hybrid joints. The effects of adhesive thickness and various surface conditions of both adherends were examined. Among key conclusions, the study found that cleavage strength is not strongly dependent upon adhesive thickness and that polished composite gives better adhesion compared with polished steel. Test results were analysed and compared with aspects of numerical analyses. The study has also established a new methodology to test hybrid adhesive cleavage joints.     

Differential scanning calorimetry: gelatinisation of sago starch in the presence of sucrose and sodium chloride

The effect of sucrose and sodium chloride (NaCl) on sago starch gelatinisation was investigated by differential scanning calorimetry (DSC). The gelatinisation of starch in the presence of low levels of water and high levels of sucrose was studied. The gelatinisation temperature was found to increase in the presence of sucrose, whereas the gelatinisation enthalpy was unaffected. The gelatinisation temperature range was not as broad in the presence of sucrose as without sucrose. Furthermore, the shape of the gelatinisation endotherm was changed by the addition of sucrose. The double endotherm obtained in limited water–starch systems was changed into a single endotherm, similar to the endotherm obtained in excess water–starch systems at higher temperature. DSC was also used to examine the effects of water and NaCl content on the phase transitions of sago starch. Samples were adjusted to starch–water weight ratios of 2:3 and 3:2 in NaCl concentrations from 1 to 5 M . The gelatinisation temperature of sago starch increased and then decreased as the NaCl concentration increased. NaCl created similar effects on the endotherms with excess water content and on the first endotherm with limited water content. © 1999 Society of Chemical Industry     

Compatibilization of poly(vinylidene fluoride)/nylon 6 blends by carboxylic acid functionalization and metal salts formation. I. Grafting reactions and morphology

An investigation was carried out to determine the feasibility of producing compatibilized blends of PVDF and nylon 6 using a procedure involving the grafting of carboxylic acid groups on the chains of either polymer component and, subsequently, producing the corresponding metal salts. The grafting reactions were carried out by irradiating the polymer with γ-rays at 15 kGy, followed by treatments in aqueous solutions of methacrylic acid. These conditions were established from preliminary work which also revealed that this monomer gives higher grafting yields than acrylic acid. The grafted polymers were found to have a heterogeneous structure, attributed to the presence of oligomeric, rather than unitary, side groups. Nevertheless, these modifications of the polymer chains were found to give rise to well-compatibilized blends, containing co-continuous phases which became much finer through the addition of zinc acetyl acetonate. FTIR analysis showed that the enhanced compatibilization resulted from the reactions between the acid groups in the PVDF component and the terminal amine groups of the polyamide chains. Since the addition of zinc acetyl acetonate was found to reduce the yield of amidized groups, it was inferred that the enhanced compatibilization has resulted from the complexation of zinc cations with the amide groups in the nylon 6 chains, which are shared with the carboxylate anions of the grafted PVDF component. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1911–1923, 1997