Impact of Infrared Broiling on the Thiamin and Riboflavin Retention and Sensory Quality of Salmon Steaks for Foodservice Use

Salmon steaks were broiled using infrared radiation and compared to convection oven baking. Total percent cooking losses of moisture and fat content were not significantly different. Samples broiled by infrared oven retained 87.2% and 92.6% of thiamin and riboflavin content, respectively. There were no significant differences for vitamin retention by both methods. Appearance and color of salmon steaks baked in the convection oven were rated significantly higher than infrared broiled samples. Tenderness and juiciness scores for infrared broiled steaks were significantly higher than those for convection oven baked steaks. There were no significant differences in panel scores for odor, flakiness, flavor and overall acceptability of steaks prepared by both methods.     

Reduction of Stachyose in Legume Flours by Lactic Acid Bacteria

Pinto bean and fiend pea flours were inoculated with different populations of Lactobacillus fermentum or Lactobacillus plantarum, adjusted with water to 20% moisture and incubated. Amount of stachyose and number of lactobacilli were determined after 24, 48 and 72 hr. After 72 hr incubation stachyose was reduced in ointo bean (bv 27%) and field pea (43%) flours. Duration of incubation was the only factor which influenced stachyose reduction. Amount of inoculum and type of bacteria were of minor importance. Number of bacteria decreased significantly during incubation.     

Reduction of Flatulence-Causing Sugars by High Temperature Extrusion of Pinto Bean High Starch Fractions

Pinto bean high starch fractions were extruded using a Wenger TX-52 twin screw extruder. The effect of process temperature and moisture in the barrel on flatulence-causing sugars was investigated. Levels of flatulence causing sugar were lower in extruded compared to non-extruded samples with higher reduction at higher process temperature. Sugar content decreased from 5.29% in nonextruded samples to 3.69% in samples extruded at 163°C. Moisture content in the extruder barrel did not significantly affect sugars in the samples. Raffinose and stachyose contents were reduced 47 to 60% by extrusion.     

Water Stress and Quality Decline during Storage of Tropical Leafy Vegetables

The effect of water stress (excessive water loss) on postharvest quality during storage of tropical leafy vegetables Brussica junceu L. and Amaranthus caudatus L. at ambient (24°/28°C) and low temperature (2°/4°C) regimes has been investigated. Exposed, nonsealed B. juncea and A. caudutus leaves lost water rapidly during storage at either temperature regime resulting in accelerated decrease in leaf turgidity (wilting), chlorophyll, ascorbic acid and soluble protein content, and an increase in amino acids, in the stressed leaves. Alleviation of water stress by sealing the leaves with thin plastic film restricted chlorophyll, soluble protein and ascorbic acid loss, particularly when the leaves were cooled, and maintained their turgidity. Both leafy vegetables appeared tolerant to chilling injury.     

Activation Mechanisms of Pro-Phenoloxidase on Melanosis Development in Florida Spiny Lobster (Panulirus argus) Cuticle

Phenoloxidase (PO), pro-PO [1] and pro-PO [2], isolated from cuticular extracts of early premolt spiny lobster, resolved into doublets of molecular weights 156, 151, and 96.0, 93 kD, respectively. Trypsin-activated forms of pro-PO [1] and pro-PO [2] were 123 and 83.6 kD, respectively. Apparently melanosis of shell and hyperdermal tissue in lobsters was related to stage of molt. The pro-PO forms were activated in vitro by extracts of molting fluid which is secreted into the cuticle just before molt, and the activated PO co-migrated in SDS-PAGE with the endogenously activated PO. The molting fluid was hypothesized to be the source of the natural activator(s) of pro-PO.     

Minimisation of total tardiness for identical parallel machine scheduling using genetic algorithm

In recent years research on parallel machine scheduling has received an increased attention. This paper considers minimisation of total tardiness for scheduling of n jobs on a set of m parallel machines. A spread-sheet-based genetic algorithm (GA) approach is proposed for the problem. The proposed approach is a domain-independent general purpose approach, which has been effectively used to solve this class of problem. The performance of GA is compared with branch and bound and particle swarm optimisation approaches. Two set of problems having 20 and 25 jobs with number of parallel machines equal to 2, 4, 6, 8 and 10 are solved with the proposed approach. Each combination of number of jobs and machines consists of 125 benchmark problems; thus a total for 2250 problems are solved. The results obtained by the proposed approach are comparable with two earlier approaches. It is also demonstrated that a simple GA can be used to produce results that are comparable with problem-specific approach. The proposed approach can also be used to optimise any objective function without changing the basic GA routine.     

Influence of the concentration of carbon nanotubes on electrical conductivity of magnetically aligned MWCNT–polypyrrole composites

The goal of this work is to study the effect of high magnetic pulses on electrical property of carbon nanotube–polypyrrole (CNT–PPy) composites with different CNT concentrations. CNT–PPy composites are produced in fractions of 1, 5 and 9 wt%. During the polymerization process, the CNTs are homogeneously dispersed throughout the polymer matrix in an ultrasonic bath. Nanocomposite rods are prepared. After exposure to 30 magnetic pulses, the resistivity of the rods is measured. The surface conductivity of thin tablets of composites is studied by 4-probe technique. The magnitude of the pulsed magnetic field is 10 Tesla with time duration of 1.5 ms. The results show that after applying 30 magnetic pulses, the electrical resistivity of the composites decreases depending on the concentration of CNTs in the composites. The orientation of CNTs is probed by atomic force microscopy (AFM) technique. AFM images approved alignment of CNT–polymer fibres in the magnetic field. We found that the enhancement in the electrical properties of CNT–PPy composites is due to rearrangement and alignment of CNTs in a high magnetic field. The stability of nano-composites is studied by Fourier transform infrared spectroscopy.     

Development and antibacterial performance of silver nanoparticles incorporated polydopamine–polyester-knitted fabric

Metallization is one of the finishing processes in textile treatment that can produce multifunctional effects. The present study dealt with the development of an antibacterial polyester-knitted fabric via facile and green impregnation of silver nanoparticles (SNPs). This was done by applying a polymeric foundation on the polyester-knitted fabric by simply dip-coating in the aqueous solution of dopamine. Then the SNPs were in situ fabricated and impregnated on the surface of polydopamine-modified polyester-knitted fabric in an aqueous solution of AgNO₃ at room temperature. Thus, a multi-functional finishing of polyester-knitted fabric was done. The Fourier transform infrared spectroscopy was done to confirm the polymer attachment. Scanning electron microscopy equipped with energy dispersive X-ray was done to confirm the presence of SNPs on treated fabric. The crystallography of the treated surface was examined by X-ray diffraction. The antibacterial properties of treated fabrics against broad spectrum bacterial strains were investigated and found significant.     

A new approach for elasto-plastic finite strain analysis of cantilever beams subjected to uniform bending moment

The reliability and limits of solutions for static structural analysis depend on the accuracy of the curvature and deflection calculations. Even if the material model is close to the actual material behavior, physically unrealistic deflections or divergence problems are unavoidable in the analysis if an appropriate fundamental kinematic theory is not chosen. Moreover, accurate deflection calculation plays an important role in ultimate strength analysis where in-plane stresses are considered. Therefore, a more powerful method is needed to achieve reliable deflection calculation and modeling. For this purpose, a new advanced step was developed by coupling the elasto-plastic material behavior with precise general planar kinematic analysis. The deflection is generated precisely without making geometric assumptions or using differential equations of the deflection curve. An analytical finite strain solution was derived for an elasto-plastic prismatic/non-prismatic rectangular cross-sectioned beam under a uniform moment distribution. A comparison of the analytical results with those from the Abaqus FEM software package reveals a coherent correlation.