Sensory,physical and chemical characteristics of cooked ham manufactured from rapidly chilled and earlier deboned M. semimembranosus

Effects of rapid chilling of carcasses (at − 31 °C in the first 3 h of chilling, and then at 2–4 °C) and earlier deboning (8 h post-mortem), compared to rapid (till 24 h post-mortem) and conventional chilling (at 2–4 °C, till 24 h post-mortem), on quality characteristics of pork M. semimebranosus and cooked ham were investigated. Quality measurements included pH value, colour (CIEL*a*b* values) and total aerobic count of M. semimebranosus, as well as sensory (colour, juiciness, texture, and flavour), physical (pH value, colour – CIEL*a*b* values and texture – Warner–Bratzler shear and penetration forces) and chemical (protein, total fat, and moisture content) characteristics of cooked ham. The cooked ham was manufactured from pieces of M. semimebranosus with ultimate lightness (CIEL* value) lower than 50. Rapid chilling and earlier deboning significantly increased quantity of M. semimebranosus desirable for cooked ham manufacturing. Earlier start of pork fabrication did not affect important quality characteristics of cooked ham.     

Simple and Rapid Method for the Simultaneous Determination of Cholesterol and Retinol in Meat Using Normal-Phase HPLC Technique

A direct saponification and normal-phase high-performance liquid chromatography (NP-HPLC) procedure was developed for simultaneous determination of cholesterol and retinol in meat. A normal-phase silica column fitted with diode array detection at 208 nm for cholesterol and fluorescence detection (λ-excitation 344 nm/λ-emission 472 nm) for retinol, with mobile phase consisting of 2% (v/v) 2-propanol in n-hexane was used. Cholesterol was eluted at 10 min and retinol at 12.66 min. High linearity (R ² > 0.9996 for both compounds) in calibration range was obtained. The LOD and LOQ values show the high sensitivity of the developed methodology for simultaneous determination of cholesterol and retinol in meat. Recovery results obtained in this study (98.67–102.14% for cholesterol and 91.72–98.27% for retinol) were between AOAC recommendations to validated method and were comparable to most recent studies in precision and accuracy. In addition, the present method showed high repeatability and reproducibility. As a general conclusion, the results indicate that the direct saponification, extraction, and HPLC analysis is an adequate method for cholesterol and retinol analysis in meat samples.     

DNS exfiltration detection in the presence of adversarial attacks and modified exfiltrator behaviour

International Journal of Information Security - The Domain Name System (DNS) exfiltration is an activity in which an infected device sends data to the attacker’s server by encoding it in DNS...     

Acoustic resonance in plate heat exchangers: Résonance acoustique des échangeurs de chaleur à plaques

A ‘whistling' sound, which develops under transient conditions in some automobile air conditioning systems equipped with plate type evaporators, was identified as acoustic resonance. The ‘whistle' was reproduced in the laboratory under steady-state conditions. Testing of these heat exchangers was done first with R134a and then with nitrogen. Nitrogen testing proved to be much faster and easier and provided results comparable to the results obtained using R134a. The evidence presented in this work suggests that the acoustic resonance in this type of heat exchanger is similar in nature to the acoustic resonance problems reported for tube array in duct type heat exchangers. This is to the authors' knowledge the first time that acoustic resonance problems have been reported in the literature for plate heat exchangers.     

Effect of Storage in a Low Oxygen Gas Atmosphere on Colour and Sensory Properties of Pork Loins

The objective of this study was to examine the quality characteristics of packaging materials and packaging units, and the viability and acceptability of the colour and sensorial properties of fresh pork meat during storage in low oxygen and high carbon dioxide modified atmosphere packaging up to 16 days at two temperatures (0°C and 4°C), as well as the sensorial properties of cooked meat. Packaging materials had good mechanical and barrier properties and were suitable for packaging in selected atmosphere. The concentration of oxygen during the whole storage period was less than 0.5% at both temperatures. The proportion of red colour (a*) was successfully maintained although the colour was slightly darker (L*) and the sensory value was lower when evaluated at the end of the storage period. Based on the obtained results and discussion, it can be concluded that samples packaged in a modified atmosphere with 40% CO₂ and 60% N₂ can be stored at 0°C for 15 days and at 4°C for 10 days. Samples had a good sensory quality until the 16th day, with the best results achieved on the 7th day. Copyright © 2013 John Wiley & Sons, Ltd.     

Failure of the negative voltage regulator in medium-photon-energy X radiation fields

Negative voltage regulators were examined in the effective 60-keV and 170-keV bremsstrahlung fields, as well as in the field of ⁶⁰Co gamma-radiation. Most devices irradiated in the fields of medium-dose-rate breaking radiation failed to operate after absorption of very small total doses of ionizing radiation, in the range of 37–132 Gy(SiO₂). However, all samples irradiated in the gamma radiation environment remained completely functional, even after deposition of a total dose of 500 Gy(SiO₂). Devices irradiated with higher input voltages failed after absorption of low total doses, whereas the load current increase mitigated and even prevented circuit failures in X radiation fields. The high radiation sensitivity of the LM2990T-5 voltage regulators operating in the bremsstrahlung fields was a consequence of the dose enhancement on the gold–aluminum connection between the silicon chip and ground contact. Computer model simulations indicated that the primary failure mechanisms were the generation of radiation-induced leakage currents alongside the npn transistors in the operational amplifier circuit. The difference between the voltage regulator responses in various bremsstrahlung environments was affected by the time-dependent effects, leading to the partial recovery of radiation-induced trapped charge.     

Solution Equilibria between Aluminum(III) Ion and L-histidine or L-tyrosine

Toxic effects due to high aluminum body loads were observed in a number of conditions following ingestion of Al-containing antacids. Bio-availability of aluminum depends not only on the solubility of the ingested salt but also on the physico-chemical properties of the soluble Al complexes formed in body fluids. Amino acids may, upon interaction with Al-salts, form absorbable Al-complexes. Hence, complex formation equilibria between Al(3+) and either, L- histidine or L-tyrosine were studied by glass electrode potentiometric (0.1 mol/L LiCl ionic medium, 298 K), proton NMR and uv spectrophotometric measurements. Non linear least squares treatment of the potentiometric data indicates that in the concentration ranges: 0.5相似文献   

Sustainable development of the Belgrade energy system

Cities are the most important energy consumers of any country in all energy vector components. Nowadays, Belgrade as a cultural, educational, scientific, administrative, political, and business center of the region with its own structure of production, transportation, services, and urban system, represents significant consumer of different energy forms. Only useful and final energy is delivered to energy consuming sectors of a city. Simulation model MAED was used in this paper to estimate energy demand in city for a long time period. On the basis of energy demand forecast for three major ‘energy consumers’ (sectors of household/service, industry, and transportation) until 2020, the sustainable development ‘scenarios’ of Belgrade energy system are developed (2005–2010, 2010–2015, 2015–2020). For each ‘scenario’, the energy systems of primary resources are determined so to satisfy the predicted differences in energy consumption for the mentioned time intervals until 2020. In this case different ‘scenarios’ are evaluated. The evaluation of ‘scenarios’ sustainability is obtained by method of multi-criteria analysis. Using energy indices for sustainable development, the following indices are taken into consideration for the assessment of scenario sustainability: economical, social, and environmental. The obtained results can be used by experts in decision-making process.     

Single core fully integrated CMOS micro-fluxgate magnetometer

A new fully integrated 2D micro-fluxgate magnetometer is presented. This magnetometer is integrated in a standard CMOS process and uses a ferromagnetic core integrated on the chip by a photolithographic post-process compatible with the integrated circuit technology. The cross-shaped ferromagnetic core is placed diagonally above four excitation coils, two for each measurement axis. A novel electronic signal extraction technique is presented. The integrated 2D magnetometer exhibits a sensitivity of 160 V/T and a linear range of ±50 μT. The magnetic equivalent noise spectral density is 70 nT/√Hz at 1 Hz, and the total power consumption is as low as 17 mW for the 5 V power supply.     

Effect of Starter Culture Addition and Processing Method on Proteolysis and Texture Profile of Traditional Dry-Fermented Sausage Petrovská klobása

Proteolysis and texture profile of Petrovská klobása, made with addition of starter culture, were investigated during the ripening in different conditions (traditional versus industrial). Due to intensive degradation of myofibrillar proteins, significant increases of non-protein nitrogen and free amino acids nitrogen contents were registered in all samples. Similar proteolytic changes were found in both starter and non-starter sausages, but were more pronounced in samples ripened in industrial room. In relation to ripening conditions hardness and chewiness differed significantly, while starter culture had significant effect only on hardness of sausages processed in industrial room.