Impact and prospect of the fourth industrial revolution in food safety: Mini-review

Food Science and Biotechnology - The fourth industrial revolution represented by big data and artificial intelligence (AI), already had a significant impact on the food industry. In this review,...     

Application of ohmic heating for the inactivation of microbiological hazards in food products

Ohmic heating has long been used to inactivate pathogens in food products. Several research investigations on the use of ohmic heating technology in the inactivation of microbial hazards in food products are discussed in this review. These studies are discussed under the following sub-headings: (a) inactivation of microbiological hazards, (b) in combination treatments with other sanitizing technologies, and (c) mathematical modeling, all of which are of long-standing interest. In this review, we evaluate ohmic heating as a rapid and volumetric heating process that inactivates microbiological hazards in food products. We also examine ohmic heating-based combination treatments as promising methods to maximize microbial inactivation efficacy and minimize the quality deterioration of food products. We first highlight the fact that most researchers had an interest in the inactivation of vegetative pathogens, whereas only a few focused on the inactivation of bacterial spores. In general, significantly higher treatment conditions were needed to inactivate bacterial spores (>95°C) than vegetative pathogens (>50°C). Studies on the inactivation of viral pathogens by ohmic heating are limited, and further research is needed in this field. In the first part of this review, the nonthermal effects of ohmic heating are also discussed, which is a popular topic in the food industry. Cumulatively, research suggests that that these nonthermal effects are dependent on the treatment conditions and the electrical conductivity of different food samples. Therefore, we suggest that focus should be on the thermal rather than the nonthermal effects of ohmic heating when considering the application of this technology to inactivate pathogens. Finally, we introduced combination technology based on ohmic heating and mathematical modeling, which are of interest recently.     

Antibacterial and in vitro antidementia effects of aronia (Aronia melanocarpa) leaf extracts

Food Science and Biotechnology - This study investigated the antibacterial and in vitro antidementia effects of aronia (Aronia melanocarpa) leaf extracts from 3 cultivars (Nero, Viking, and...     

Highly strained InGaP/InGaAs p-HEMT using reduced area growth

Highly strained InGaP/In_0.33Ga_0.67As pseudomorphic high electron mobility transistor (p-HEMT) structures were grown on patterned GaAs substrates. Performance of the highly strained p-HEMTs grown on patterned substrates was compared with that of highly strained p-HEMTs and conventional InGaP/In_0.22Ga_0.78 As p-HEMTs grown on nonpatterned substrates. The highly strained p-HEMTs grown on patterned substrates showed substantial improvements in dc (transconductance and drain saturation current) and rf (cutoff frequency: f_T and maximum oscillation frequency: f_max ) performances as compared with those of the p-HEMTs grown on nonpatterned substrates. The results indicate the potential of highly strained p-HEMTs using reduced area growth for high-speed device applications     

Numerical investigation on NOX formation in oxygen-CH4 MILD combustion with air leakage

In this paper, we focus on formation of NO_X under oxy-fuel MILD combustion using JHC (jet-in hot co-flow) burner. The effect of the different oxygen dilution ratio in the co-flow is analyzed for MILD combustion formation and also for characterizing NO_X emission. RANS (Reynolds averaged Navier Stokes) with the modified k-ε equation and EDC (eddy dissipation concept) model were applied for 2D-axisymmetric computational domain using the Ansys Fluent. It is found that the effect of the oxygen concentration rather than the composition of dilution gas is more significant for the formation of the MILD combustion and as the oxygen concentration of the dilution gas increases under MILD combustion conditions, the region with D_a < 1 expressed as MILD regime tends to be decreased. The effect of a diluted oxygen concentration in the oxy-fuel combustion on NO_x emission under MILD condition is found to be much greater than the amount of air leakage into co-flow, and NO emissions are almost unaffected by the increase of N₂ concentration in case of MILD combustion condition within practical air leak ranges.

     

Hydrodynamic characteristics of cold-bed circulating fluidized beds for the methanol to olefins process

The effects of the riser inlet velocity (2.2–3.9 m/s), seal-pot inlet velocity (2.4–7.1 U _mf ), aeration flow rate (2.5×10^?7–3.7×10^?6 m³/s) in seal-pot, and solid inventory (0.15–0.2 kg) on the hydrodynamic characteristics of a 9 mm-ID×1.9 m-high cold-bed circulating fluidized bed for methanol to olefins (MTO) process were investigated. FCC (Engelhard; 82.4 μm) particles were used as bed particles. Most of the experimental flow regimes were observed in fast fluidization and pneumatic transport regimes. The axial solid holdup in a riser increased with increasing solid mass flux and solid inventory. Solid mass flux increased proportionally until reaching a maximum value and then decreased with increasing seal-pot inlet velocity. The obtained hydrodynamic characteristics in the cold-bed circulating fluidized beds were compared with previous results.     

Digital textile printing (DTP) wastewater treatment using ozone and membrane filtration

Digital textile printing (DTP) is considered as an environmentally benign process because its wastewater production is relatively small compared with the conventional textile printing system. DTP is usually practiced at building office in an urban area rather than in a textile industrial complex, so that process development for on-site treatment of the DTP wastewater is currently needed. The aim of this study was to propose a DTP wastewater treatment system suitable for operation in building and to verify if the proposed system has a rationale treatment system should be compact and reliable because it should be installed near the DTP system. Thus, a hybrid system consisting of ozone, ultrafiltration (UF) and reverse osmosis (RO) was proposed for treatment of DTP wastewater. Prior to UF and RO, ozone was introduced to the DTP wastewater to reduce organic loadings to membrane filtration as well as to treat the concentrates recycled from UF and RO. When ozone was injected with C-T value of 255 g·s/L, the removal efficiency of COD and color was 63 and 81%, respectively. Ozonation of the DTP wastewater led to aggregation of colloidal particles, so that the cake resistance (R_c) calculated after ozone and UF was lower than that of the control (= without ozonation), suggesting that pre-ozonation is beneficial to not only flux enhancement but also to good permeate water quality. Further treatment of UF permeates using RO was carried out since the UF permeates was not enough for direct discharge or reuse. Final effluents through the whole process of ozonation, UF and RO met the criteria of direct discharge and reuse, suggesting that the proposed hybrid system could be used for DTP wastewater treatment satisfactorily.     

Recent (2011–2017) foodborne outbreak cases in the Republic of Korea compared to the United States: a review

This study analyzes and compares foodborne disease outbreaks reported in the Republic of Korea (KR) and the United States (US) during 2011-2017. The foodborne outbreaks data in the KR and the US were collected from the Ministry of Food and Drug Safety and from the Surveillance for Foodborne Disease Outbreaks United States, respectively. The average number of outbreaks and illness population were higher in the US than in the KR, but the KR’s illness ratio considering population size was 2.4 times higher than that of the US. When the sites of outbreaks compared, the number of illness was the highest at schools in the KR whereas outbreaks at restaurants were more frequent in the US. In the KR, bacterial infections were the primary cause of outbreaks while bacterial and viral infections accounted for the largest share of outbreaks in the US. Specifically, pathogenic E. coli presented a significant risk in the KR whereas Salmonella was the most prevalent in the US. These results indicate that the main microbiological targets for detection and control in the KR should differ from the US, which should be considered for developing food safety related policies.     

Fabrication of monodisperse silica spheres using statistical design of experiments

The statistical design of experiments was successfully carried out in order to synthesize monodisperse silica spheres using a fractional factorial design with a resolution of V. In this design, the input variables were the temperature, the concentration of NH₃, the concentration of TEOS, the methanol/n-prophyl alcohol ratio, and the distilled water. The output variables were the particle size, standard deviations, and the degree of agglomeration. Simultaneous consideration of the particle characteristics allowed for an optimum regime in the experimental conditions in addition to an understanding of the experimental variables. The concentrations of TEOS and distilled water are determined to be statistically significant variables for the controlling of the particle sizes. The size of the monodisperse silica spheres was found to be approximately 400 nm.