Smart packaging: sensors for monitoring of food quality and safety

The development of chemical sensors and biosensors over several decades has been investigated resulting in novel and very interesting sensor devices with great promise for many areas of applications including food technology. The incorporation of such sensors into the food packaging technology has resulted what we call smart or intelligent packaging. These are truly integrated and interdisciplinary systems that invoke expertise from the fields of chemistry, biochemistry, physics and electronics as well as food science and technology. Smart packaging utilises chemical sensor or biosensor to monitor the quality & safety of food from the producers to the costumers. This technology can result in a variety of sensor designs that are suitable for monitoring of food quality and safety, such as freshness, pathogens, leakage, carbon dioxide, oxygen, pH, time or temperature. Thus, this technology is needed as on-line quality control and safety in term of consumers, authorities and food producers, and has great potential in the development of new sensing systems integrated in the food packaging, which are beyond the existing conventional technologies, like control of weight, volume, colour and appearance.     

Crystallization studies of Al<Subscript>85</Subscript>Y<Subscript>10</Subscript>Fe<Subscript>5−x</Subscript>Ni<Subscript>x</Subscript> (x = 0, 2.5, 5) alloys

The crystallization behavior of melt-spun A₈₅Y₁₀Fe_5−xN_x (x=0, 2.5, 5) amorphous alloys has been investigated by a combination of differential scanning calorimetry (DSC) and x-ray diffractometry (XRD). XRD traces of these alloys consisted of a single broad peak corresponding to fully amorphous structure. Continuous DSC results showed that, the first crystallization peak temperature of Al₈₅Y₁₀Fe₅ amorphous alloy was about 60 K higher than that of Al₈₅Y₁₀Ni₅. The activation energies for the first crystallization peak increased from 210 kJ/mol for Al₈₅Y₁₀Ni₅ to 280 for Al₈₅Y₁₀Fe₅. These results indicate that 5 at.% substitutions Ni by Fe increases the stability of the amorphous phase.     

Interfacial microstructure and strength of brazed copper/porous copper foam towards the effect of porous copper foam pore density and brazing holding time

The porous copper foam was sandwiched between two coppers plate and then brazed using copper-tin (9.7 %)-nickel (5.7 %)-phosphorus (7 %) filler foil. Brazing process was conducted to joint copper/porous copper foam by evaluating the effect of porous copper foam pore densities [pore per inch (PPI)] and brazing holding times. The brazed joint interface of copper and porous copper foam was characterised using Field emission scanning electron microscopy and Energy-dispersive x-ray spectroscopy for the microstructure and elemental composition analysis, respectively. X-ray diffraction analysis was carried out on the shear fractured surfaces of brazed copper and porous copper foam for phase determination. The results exhibited distinct phases of copper (Cu), copper phosphide (Cu₃P), nickel phosphide (Ni₃P), and copper compound with tin (6 : 5) (Cu₆Sn₅). The filler layer was formed as an island-shaped that consists of copper phosphide and nickel phosphide. Prolong brazing holding time causes a thinner filler layer in brazing seam. While the non-uniform thickness of the filler layer was observed at different pore densities of porous copper foam. The shear strength of brazed copper/porous copper foam 15 PPI with a 10 min brazing holding time yield a maximum shear strength of 2.9 MPa.     

Fuzzy-based sustainability evaluation method for manufacturing SMEs using balanced scorecard framework

Sustainability has become a necessity, partly due to the threats created by traditional manufacturing practices, and due to regulations imposed by stakeholders. Performance evaluation is an important component of sustainability initiatives in manufacturing organizations. This study proposes a sustainability evaluation method for manufacturing SMEs using integrated fuzzy analytical hierarchal process (FAHP) and fuzzy inference system (FIS) approach. The performance indicators are identified from literature considering the characteristics of SMEs. Balanced scorecard framework is used to categorize the indicators among its four aspects. The linguistic variables are used to collect the opinions of decision makers about the performance ratings and importance of the aspects and corresponding indicators. The FAHP method is applied to determine the relative weights of measures and indicators. The performance ratings of the organization with respect to indicators and relative weights of indicators are combined to obtain the weighted performance ratings. The weighted performance ratings are considered as inputs to FIS. The hierarchal FIS is applied to derive the overall sustainability performance. Using a case study of manufacturing SME, the sustainability score of the organization was elicited in accordance with this procedure. Consequently, a sensitivity analysis of the proposed method reveals the most important basic indicators affecting overall sustainability, identifying areas which decision makers should place special attention. This method can also assist managers of larger enterprises to assess the effectiveness of their sustainability strategies, especially when dealing with suppliers from the SMEs.     

Lipid and fatty acid profiles in rats consuming different high-fat ketogenic diets

High-fat ketogenic diets are used to treat intractable seizures in children, but little is known of the mechanism by which these diets work or whether fats rich in n−3 polyunsaturates might be beneficial. Tissue lipid and fatty acid profiles were determined in rats consuming very high fat (80 weight%), low-carbohydrate ketogenic diets containing either medium-chain triglyceride, flaxseed oil, butter, or an equal combination of these three fat sources. Ketogenic diets containing butter markedly raised liver triglyceride but had no effect on plasma cholesterol. Unlike the other fats, flaxseed oil in the ketogenic diet did not raise brain cholesterol. Brain total and free fatty acid profiles remained similar in all groups, but there was an increase in the proportion of arachidonate in brain total lipids in the medium-chain triglyceride group, while the two groups consuming flaxseed oil had significantly lower arachidonate in brain, liver, and plasma. The very high dietary intake of α-linolenate in the flaxseed group did not change docosahexaenoate levels in the brain. Our previous report based on these diets showed that although ketosis is higher in rats consuming a ketogenic diet based on medium-chain triglyceride oil, seizure resistance in the pentylenetetrazol model is not clearly related to the degree of ketosis achieved. In combination with our present data from the same seizure study, it appears that ketogenic diets with widely differing effects on tissue lipids and fatty acid profiles can confer a similar amount of seizure protection.