Costs and investments of implementing and maintaining HACCP in a pasteurized milk plant

Results of an economic study associated with the implementation and maintenance of HACCP in a pasteurized milk plant are presented. The GMP/SSOP pre-requisites were evaluated in the plant. Two HACCP plans were proposed: a first plan was developed under the actual operating conditions, without previous compliance of GMP/SSOP pre-requisites, and a second plan was developed considering compliance of GMP/SSOP. The cost estimation for implementation and maintenance of HACCP, with or without previous adoption of the pre-requisite programs, was performed and a comparative analysis of the estimated values was carried out. The results suggest that a previous compliance of GMP/SSOP pre-requisites is essential for developing an effective HACCP plan with a small number of critical control points, leading to lower costs and investments for implementation and maintenance of HACCP.     

Microbiological evaluation of an edible antimicrobial coating on minimally processed carrots

This work aimed to develop an edible antimicrobial coating based on a starch–chitosan matrix to evaluate its effect on minimally processed carrot by means of microbiological analyses. Coatings based on 4% yam starch (w/w) + 2% glycerol (w/w) and coatings based on 4% yam starch (w/w) + 2% glycerol (w/w) + chitosan in 0.5% and 1.5% concentrations were prepared. Samples of minimally processed carrot slices were immersed into these coatings. All the samples were placed in expanded polystyrene trays, wrapped in polyvinylchloride film and stored at 10 °C/15 days. During storage, all the samples had counting <100 CFU/g for Staphylococcus aureus and <3 MPN/g for Escherichia coli. Starch + 0.5% chitosan coating controlled the growth of mesophilic aerobes, yeasts and molds and psychrotrophs during the first five days of storage, ultimately presenting reductions of only 0.64, 0.11 and 0.16 log cycles, respectively, compared to the control. Starch + 1.5% chitosan coated samples showed reductions in mesophilic aerobes, mold and yeast and psychrotrophic counting of 1.34, 2.50 and 1.30 log cycles, respectively, compared to the control. The presence of 1.5% chitosan in the coatings inhibited the growth of total coliforms and lactic acid bacteria throughout the storage period. The use of edible antimicrobial yam starch and chitosan coating is a viable alternative for controlling microbiological growth in minimally processed carrot.     

Effect of the Structure of Cations and Anions of Ionic Liquids on Separation of Aromatics from Hydrocarbon Mixtures

1. Introduction Benzene is a key chemical in the chemical industry, used as the raw material for producing polymer precursors, solvents, dyes, drugs, herbicides, and so on. The world production of benzene is more than 2.0×107 tons/year (Vervalin, 1991; Weissermel and Arpe, 1993; Villaluenga and Tabe-Mohammadi, 2000). Before World War II, benzene was mainly produced from coal, but nowadays more than 90% is obtained from petroleum, mainly from catalytic reformates and FCC gasoline, and by …     

Chemical characteristics of spice paprika of different origins

Spice paprika powders from Bulgaria, China, Hungary, Peru, Serbia and Spain were examined to identify the most important differences in their major characteristics and to attempt to find chemical components revealing their origin. Bioactive components, contaminants, aroma and microbiological properties were determined: the amount of carotenoids, tocopherols, ascorbic acid and mycotoxins were determined by HPLC, flavoring properties by GC-MS, lead and cadmium content by atomic absorption spectrophotometry. Carotenoids were found at the highest concentration in samples from Peru and Spain and at the lowest, in Serbian samples. The concentrations of total tocopherol and ascorbic acid were found to be greater in samples from Hungary than from China. Aroma components characteristic to the location were detected in samples from each country of origin. The level of microbiological contamination was acceptable, while contaminants were found in Serbian, Spanish, Peruvian and Chinese samples. The effect of sample origin was also investigated using near infrared spectroscopy.     

New Frontiers on van der Waals Layered Metal Phosphorous Trichalcogenides

The exponentially growing works on 2D materials have resulted in both high scientific interest and huge potential applications in nanocatalysis, optoelectronics, and spintronics. Of especial note is that the newly emerged and promising family of metal phosphorus trichalcogenides (MPX₃) contains semiconductors, metals, and insulators with intriguing layered structures and architectures. The bandgaps of the members in this family range from 1.3 to 3.5 eV, significantly enriching the application of 2D materials in the broad wavelength spectrum. In this review, emphasizing their remarkable structural, physicochemical, and magnetic properties, as well as the numerous applications in various fields, the innovative progress on layered MPX₃ crystals is summarized. Different from other layered materials, these crystals will advance a fascinating frontier in magnetism and spintronic devices with their especially featured atomic layered nanosheets. Thus, their crystal and electronic structures, along with some related researches in magnetism, are discussed in detail. The assortments of growth methods are then summarized. Considering their potential applications, the prominent utilization of these 2D MPX₃ nanoscrystals in catalysis, batteries, and optoelectronics is also discussed. Finally, the outlook of these kinds of layered nanomaterials is provided.     

Power splitting–based energy‐harvesting protocol for wireless‐powered communication networks with a bidirectional relay

In this paper, we apply the power splitting–based energy‐harvesting protocol to enhance the transmission between a wireless access point and a mobile user via a helping relay. The mobile user exploits the energy supplied by the access point and forwarded by the relay to transmit its own data back to the access point, again with the helping of the relay. Here, the effect of various system parameters, including power‐splitting factor and the power‐to‐noise ratio on the system performance, is rigorously studied, with closed‐form expressions for the outage probability and system throughput as the results. Furthermore, we figure out the optimal power‐splitting ratio at which the information throughput from the user to the AP is maximized, subject to the constraint on the transmitting power at the access point. All above analytical results are also supported by Monte Carlo simulation.     

High‐Throughput Fabrication of Au–Cu Nanoparticle Libraries by Combinatorial Sputtering in Ionic Liquids

Materials libraries of binary alloy nanoparticles (NPs) are synthesized by combinatorial co‐sputter deposition of Cu and Au into the ionic liquid (IL) 1‐butyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide ([C₁C₄im][Tf₂N]), which is contained in a micromachined cavity array substrate. The resulting NPs and NP‐suspensions are investigated by transmission electron microscopy (TEM), X‐ray diffraction (XRD), UV‐Vis measurements (UV‐Vis), and attenuated total reflection Fourier transformed infrared (ATR‐FTIR) spectroscopy. Whereas the NPs can be directly observed in the IL using TEM, for XRD measurements the NP concentration is too low to lead to satisfactory results. Thus, a new NP isolation process involving capping agents is developed which enables separation of NPs from the IL without changing their size, morphology, composition, and state of aggregation. The results of the NP characterization show that next to the unary Cu and Au NPs, both stoichiometric and non‐stoichiometric Cu–Au NPs smaller than 7 nm can be readily obtained. Whereas the size and shape of the alloy NPs change with alloy composition, for a fixed composition the NPs have a small size distribution. The measured lattice constants of all capped NPs show unexpected increased values, which could be related to the NP/surfactant interactions.     

Effects of PCBM concentration on the electrical properties of the Au/P3HT:PCBM/n-Si (MPS) Schottky barrier diodes

In this study, the gold/poly(3-hexylthiophene):[6,6]-phenyl C61 butyric acid methyl ester/n-type silicon (Au/P3HT:PCBM/n-Si) metal–polymer–semiconductor (MPS) Schottky barrier diodes (SBDs) were investigated in terms of the effects of PCBM concentration on the electrical parameters. The forward and reverse bias current–voltage (I–V) characteristics of the Au/P3HT:PCBM/n-Si MPS SBDs fabricated by using the different P3HT:PCBM mass ratios were studied in the dark, at room temperature. The main electrical parameters, such as ideality factor (n), barrier height (Φ_B0), series resistance (R_s), shunt resistance (R_sh), and density of interface states (N_ss) were determined from I–V characteristics for the different P3HT:PCBM mass ratios (2:1, 6:1 and 10:1) used diodes. The values of n, R_s, Φ_B0, and N_ss were reduced, while the carrier mobility and current were increased, by increasing the PCBM concentration in the P3HT:PCBM organic blend layer. The ideal values of electrical parameters were obtained for 2:1 P3HT:PCBM mass ratio used diode. This shows that the electrical properties of MPS diodes strongly depend on the PCBM concentration of the P3HT:PCBM organic layer. Moreover, increasing the PCBM concentration in P3HT:PCBM organic blend layer improves the quality of the Au/P3HT:PCBM/n-Si (MPS) SBDs which enables the fabrication of high-quality electronic and optoelectronic devices.     

Correction to: Cloud-based vehicular networks: a taxonomy,survey, and conceptual hybrid architecture

Wireless Networks - The original version of this article unfortunately contained a mistake in the title. The correct title has been published with this erratum.