Nano-Rheological Behaviour of Cassava Starch-Zinc Nanocomposite Film under Dynamic Loading for High Speed Transportation of Packaged Food

This research was undertaken to determine the nano–rheological behaviours of cassava starch–zinc–nanocomposite films under dynamic loading for assessing their suitability as food packaging materials in high speed transportation. The films, with thickness ranging between 15 ± 0.22–17 ± 0.13 µm, were prepared by casting mixtures of 24 g cassava starch, 45–55% (w/w) glycerol and 0–2% (w/w) zinc nanoparticles in plastic moulds of 8–12 mm depths. The effects of the nanoparticles, thickness and glycerol on the rheological properties of the films, including the Young’s modulus, creep, hardness and plasticity index were determined using nanoindentation technique. The results show that the Young’s modulus and hardness of the films varied inconsistently with glycerol concentration and nanoparticles due probably to their isotropic nature and sensitivity to slight change in load. The plasticity index was lower for 15 µm film, which absorbed 40 pNm and dissipated 0.5 pNm during loading and unloading stages, respectively. The response of the 15 µm film to creep was higher than 16 µm and 17 µm films, and this may be consequence of lower wear at higher loads. This implies that the nanocomposite film might be suitable for high speed transportation of packaged food

Mammograms and breast arterial calcifications: looking beyond breast cancer: a preliminary report

<p>Abstract</p> <p>Background</p> <p>To find out the prevalence, clinical and biochemical correlates of Breast Artery Calcification (BAC) in the Nigerian women.</p> <p>Findings</p> <p>This is a cross sectional study involving 54 consecutive adult female subjects sent to the Radiology Department of the Lagos State University Teaching Hospital (LASUTH), Ikeja-Lagos, Nigeria for screening and diagnostic mammography. The study was carried out for a period of five months.</p> <p>The prevalence of BAC was 20%. Ageing was found to be related to BAC. Cardiovascular risk factors including diabetes mellitus (DM), hypertension, obesity, alcohol ingestion, use of oral contraceptives and hormone replacement therapy, were not significantly related to the presence of BAC in this study.</p> <p>Conclusion</p> <p>This study showed that though the presence of BAC in a mammogram is related to age, it may not predict or serve as a significant marker for cardiovascular diseases (CVD) in women in our environment.</p

EFFECT OF PULSED ELECTRIC FIELD ON STRUCTURAL MODIFICATION AND PHYSICOCHEMICAL PROPERTIES OF STARCH-BASED EDIBLE FILMS

Starch-based edible film is a novel packaging material that has gained much recognition and attention in the food industry. Its remarkable functional property like microbial deactivation without posing harmful effect on food materials is remarkable. The application of pulsed electric field (PEF) treatment to starch-based edible film is fundamental to ensuring physicochemical changes and structural modifications of films for the purpose of food safety and handling. However, the effectiveness of PEF is affected by process and product parameters, thus information on the effects of PEF treatment on structural modifications and physicochemical properties of starch-based edible film is useful to the food industry.This review provided an overview of the effects of PEF treatment on structural modifications and physicochemical properties such as density, solubility, water activity (aw) and stability of starch-based edible films. The significance of starch-based edible films to the food industry with a focus on potato, cassava, yam and taro starch sources is summarized. The PEF treatment and factors related to process and product parameters affecting its performance and its effects on structural and physicochemical properties of starch-based edible films were succinctly discussed. PEF treatment can cause microbial deactivation, influence the structural and physicochemical properties and produce edible films with much functionality. The future trends of PEF treatment on starch-based edible films should mainly focus on combining other physical treatment as an integrated way of improving the potentials of PEF towards development of a wider range of functionalized films

PROCESS OPTIMIZATION OF OIL EXPRESSION FROM WATERMELON (CITRULLUS LANATUS) SEEDS

Watermelon fruit contains large quantities of seeds and these seeds are under-utilized. It contains reasonable amount of oil (22%) which if expressed will serve as vegetable oil for human consumption or biodiesel for powering agricultural machines and boost the income of the farmers. The main objective of this research work is to study the interaction effect of operating parameters on the mechanical oil expression from the seed. The variables considered include applied pressure (85.00, 90.00, 95.00, 100.00 and 105.00 kN/mm2), roasting temperature (70.00, 80.00, 90.00, 100 and 110 °C) and moisture content (6.00, 8.00, 10.00, 12.00 and 14.00 %). A total sum of 20 batch experiments were carried out and the maximum oil yield was 13.49% (at corresponding moisture content of 6.00%, roasting temperature of 85.00oC and applied pressure of 105.00 kN/mm2 respectively) and minimum oil yield obtained was 9.41%.(at corresponding moisture content of 14.00%, roasting temperature 80 °C and applied pressure of 85.00 kN/mm2 respectively). While the optimum oil yield of 12.42% was obtained from the expression at corresponding moisture content of 6.00%, roasting temperature of 80.00ºC, and applied pressure of 105.00 kN/mm2. The result showed that the three independent variables had significant effect on oil yield and regression model equation was developed to predict the oil yield from watermelon seeds at known variables

Production, Properties and Applications of Materials-based Nano-Enzymes

Fungi and bacteria cause foodborne diseases and affect food security, which remains the main challenge of the global food industry. Nanomaterials-based enzyme (NMB) technologies play an important role in improving food security issues. This is possible since they can act quickly and efficiently on food substrates when used as biosensors to monitor and control the quality and shelf life of food. This chapter deals primarily with the applications of NMB in the food industry. The production, properties, and applications of nano-enzymes of carbon, zinc oxide, magnetite, copper, and some noble metals in the food industry were discussed. It was suggested that the material could mimic catalytic activities and compete with other naturally occurring enzymes, such as hydrolase and oxidoreductase in foods. It is hoped that this chapter will provide key insights into NMB technologies applied in the food industry.</jats:p

Effect of thickness and matrix variability on properties of a starch-based nanocomposite supple film

In this research, the effects of matrix variability and thickness on the properties of a flexible nanocomposite film were investigated. The nanocomposite film was prepared from the blends of 1 kg cassava starch, 45–55% (w/v) glycerol and 0–2% (w/v) zincnanoparticles in thickness ranging from 15 −17 µm. The barrier, mechanical, and thermal properties were determined experimentally. The optimal effects of the thickness and the matrix variability on the properties were determined using Response Surface Methodology. Results showed that the barrier properties increased with glycerol concentration but decreased with thickness. Reduced modulus and tensile strength increased with an increase in the matrix variability. The film was thermally stable up to 60.43oC with only 2% degradation. The optimal film contains 55% glycerol, 2% zinc nanoparticles with a thickness of 17 µm at a desirability index of 0.95. This can therefore be essential for industrial application</jats:p

Conceptual Design and Simulation of African Oil Bean Seed Dehuller

Dehulling is a unit operation preceding oil extraction of most agricultural products. While it is common to dehull the African oil bean seed manually, the mechanical operation of the process has not been reported. Thus, this study was undertaken to design and simulate African oil bean seed dehulling machine. The design was based on previous investigation of the physical and mechanical properties of the seed at 15 % moisture content (db), including average breaking force of the seed (1.12 kN). Computational fluid dynamic method was used to carry out machine simulation and the effect of time of machine operation on motor torque; angular velocity and linear displacement were investigated. The design results show that a 3 HP, single phase electric motor was required to power 25 mm shaft diameter of the machine. The simulation results show that the angular velocity was high as soon as the machine commences operation, but this progressively decreases with an increase in the time of operation. The reason for this may be due to a decrease in the viscous effect of the internal wall which causes the air stream flow to slow down with a resultant drop in the relative angular velocity to the surface. This implies that the machine is practicable with performance likely to decrease with time of machine operation