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In previous studies, parabens in model systems enhanced the thermal inactivation of foodborne pathogens, including Cronobacter sakazakii, Salmonella enterica serotype Typhimurium, Escherichia coli O157:H7, and Listeria monocytogenes. However, few studies have been conducted to evaluate this phenomenon in actual food systems. In the present study, the potential enhancement of thermal inactivation of C. sakazakii by butyl para-hydroxybenzoate (BPB) was evaluated in powdered infant formula (PIF) and nonfat dry milk (NFDM) in dry and rehydrated forms. When PIF was rehydrated with water at designated temperatures (65 to 80°C) in baby bottles, BPB did not enhance thermal inactivation. When rehydrated NFDM and lactose solutions with BPB were inoculated and heated at 58°C, BPB enhancement of thermal inactivation of C. sakazakii was negatively associated with the concentration of NFDM solutions in a dose-dependent manner, whereas thermal inactivation was enhanced in the presence of lactose regardless of its concentration, suggesting an interaction between proteins and BPB. Fluorescence testing further indicated an interaction between BPB and the proteins in PIF and NFDM. In inoculated dry NFDM with and without BPB stored at 24 and 55°C for 14 days, BPB did not substantially enhance bacterial inactivation. This study suggests that BPB is not likely to enhance mild thermal bacterial inactivation treatments in foods that have appreciable amounts of protein.

After studies with powdered infant formula indicated that the enhancement of thermal inactivation of Cronobacter sakazakii by butyl para-hydroxybenzoate (BPB) was blocked by high protein concentrations, we hypothesized that BPB would retain its synergistic activity in foods with limited protein and lipid concentrations. This hypothesis was tested by examining the ability of BPB to enhance the thermal inactivation of C. sakazakii 607 at 58°C in commercial apple juice, including examining the effects of pH and possible synergistic effects with malic acid. Apple juice was adjusted to designated pH values of 3.2 to 9.0, supplemented with selected concentrations of BPB (≤125 ppm), inoculated with early-stationary-phase C. sakazakii 607, and thermally treated (58°C) for 15 min with a submerged coil apparatus. The same methods were used to study the enhancement of thermal inactivation by malic acid. Samples were plated on tryptic soy agar for recovery and enumeration. Survival curves were plotted, and D-values were calculated by linear regression and compared using the Tukey honestly significant difference test. BPB significantly enhanced thermal inactivation in a concentration dependent manner, with D-values of a few seconds at the original pH (3.8). The enhancement of thermal inactivation was pH dependent over the pH range of 3.4 to 9.0. Malic acid enhanced thermal inactivation; the pH was decreased from 3.8 to 3.2. These results support the hypothesis that BPB can enhance the thermal inactivation of C. sakazakii in low-protein and low-lipid foods.

The 2014–2015 U.S. nationwide outbreak of listeriosis linked to apples used in commercially produced, prepackaged caramel apples was the first implication of whole apples in outbreaks of foodborne illnesses. Two case patients of this outbreak didn’t consume caramel apples but did eat whole apples, suggesting that contaminated whole apple may serve as a vehicle for foodborne listeriosis. The current study evaluated the effect of conventional fruit coating with wax and that of apple cultivar on the survival of outbreak-associated and non-outbreak Listeria monocytogenes strains on Red Delicious, Granny Smith and Fuji apples during 160 days under simulated commercial storage. L. monocytogenes survived in calyxes and stem ends of apples of all 3 cultivars through the duration of the experiment. After 2 months of storage, significantly (p L. monocytogenes populations were recovered from apples coated with wax than those un-waxed, regardless of the cultivar. No differences in survival amongst L. monocytogenes strains (serotypes 1/2a and 4b) from clinical, food, and environmental sources were observed. The observation that coating with wax facilitates prolonged survival of L. monocytogenes on whole apples is novel and reveals gaps in understanding of microbiological risks associated with postharvest practices of tree fruit production.

Although high-temperature heat treatments can efficiently reduce pathogen levels, they also affect the quality and nutritional profile of foods and increase the cost of processing. The food additive butyl para-hydroxybenzoate (BPB) was investigated for its potential to synergistically enhance thermal microbial inactivation at mild heating temperatures (54 to 58°C). Four foodborne pathogenic bacteria, Cronobacter sakazakii, Salmonella enterica Typhimurium, attenuated Escherichia coli O157:H7, and Listeria monocytogenes, were cultured to early stationary phase and then subjected to mild heating at 58, 55, 57, and 54°C, respectively, in a model food matrix (brain heart infusion [BHI]) containing low concentrations of BPB (≤125 ppm). The temperature used with each bacterium was selected based on the temperature that would yield an approximately 1- to 3-log reduction over 15 min of heating in BHI without BPB in a submerged coil system. The inclusion of BPB at ≤125 ppm resulted in significant enhancement of thermal inactivation, achieving 5- to >6-log reductions of the gram-negative strains with D-values of

In the summer of 2014, a multistate outbreak of listeriosis associated with contaminated stone fruit (peach and nectarine) was reported. A serotype 4b variant Listeria monocytogenes (Lm) strain of singleton Sequence Type (ST) 382 was isolated from clinical samples and stone fruit associated with the outbreak. A serotype 1/2b Lm strain of ST5, Clonal Complex 5 was isolated only from outbreak-associated stone fruit, not from clinical samples. Here we investigated the fate of the serotype 4b and 1/2b strains, at two inoculation levels (high level at 3.7 logCFU/fruit and low level at 2.7 logCFU/fruit), on the surfaces of white peach, yellow peach and yellow nectarine stored at 4 °C for 26 days. After rinsing the fruits, we determined the Lm levels in the rinsates and on the peels. We enumerated Lm using a direct plating method and compared two chromogenic agars. The Lm populations rapidly declined in the first 3 days and then declined more slowly until Day 19/21. The maximum decline was 1.6 logCFU/fruit on yellow peach inoculated with serotype 4b at high level. For fruits inoculated with high-level Lm, the lowest level of Lm (1.7 logCFU/fruit) was observed on for white peach inoculated with serotype 1/2b, and the highest level of Lm (2.6 logCFU/fruit) on Day 19/21 was observed on yellow peach inoculated with the serotype 1/2b strain. For fruits inoculated with low-level Lm, the lowest level of Lm (1.3 logCFU/fruit) was observed on yellow nectarine inoculated with either the serotype 4b or 1/2b strain, and the highest level of Lm (1.7 logCFU/fruit) on Day 19/21 was observed on yellow peach inoculated with ST382. The D-values ranged from 15 days to 28 days. Lm remained viable until the end of storage (Day 26), but the levels were not significantly different from those on Day 19/21. The types of stone fruit and Lm strain did not significantly affect the survival of Lm. These results demonstrate that contaminated stone fruit can carry a potential risk for causing listeriosis in susceptible populations. Comparison of direct plating results using two chromogenic agars showed that RAPID' L. mono and Agar Listeria Ottavani & Agosti performed equivalently for enumerating Lm on stone fruit. The fruit rinsing recovered 80% to 84% of Lm from fruit surfaces.

The scattering medium in the imaging path can affect the imaging quality of traditional ghost imaging. We propose to substitute a Gaussian light source with a Hadamard modulated light field to reduce correlated noise due to the occurrence of scattering medium and to improve the corresponding signal-to-noise ratio (SNR). In the simulation, scattering media with different intensities are applied on the test arm, and the result shows that Hadamard modulated light, with the particular orthogonality, is superior to Gaussian light. By substituting Gaussian light with Hadamard modulated light, a ghost image with higher SNR can be obtained under both weak and strong scattering.

Bohai Bay basin, the largest offshore basin of China, is located in northern China. Its oil and gas resources are commercially operated by China National Offshore Oil Corporation (CNOOC) since 1967. From 1967 to the present, more than 100 production platforms have been put into operation in a 43,000-km2 exploration area, including both development projects on the greenfield and infill projects on the brownfield. The predominant depositional environment of Bohai Bay basin is a shallow delta and a meandering river system complicated by faults, which leads to fully developed interbed interference and high geological uncertainty while drilling horizontal wells within the greenfield. For the infill projects, high water cut is the primary concern, especially after long-term development. Therefore, our trajectory must be controlled precisely in a desired position to overcome the existing or potential water issue. As a solution to these challenges, a new multilayer boundary detection service has been introduced to CNOOC for the first time. Outstanding outcomes have been observed by implementing this new multilayer boundary detection service. This innovative technology was applied to two challenging wells, well A of a development project achieved 377m measured depth (MD) lateral exposure with 100% net-to-gross (NTG) while depicting whole individual sand bodies and their mutual lateral contact relationship clearly, which not only can optimize the final NTG but also supply much detail, allowing for a more robust reservoir characterization. By using this technology on both landing and lateral section drilling for Well B of the infill project, target top was identified 3m true vertical depth (TVD) in advance and landed less than 1m below the target top with very low incident angle. Precise landing and lateral placement of horizontal wells and the use of inflow control devices for completion, have become critical to the success of this campaign. The results have shown that water cut has significantly declined from an average of 46.2% to 2.1%. This considerable decline can can bring higher recovery rate to this brownfield. Even for the entire China market, this was the first time that the new multilayer boundary detection service was introduced. This paper illustrates an exemplary case study of using this innovative technology for a better understanding of reservoir characterization and higher recovery rate while performing high quality geosteering in complex and mature reservoirs.

The Qing Huang Dao oilfield, located in the Bohai Bay has been in production for more than 10 years. To achieve production targets, many directional wells and horizontal wells were initially drilled with conventional tools and measurements. However, at the end of 2012, as the oilfield matures, the field's average water cut had reached a high of 86.4%.Following a multidisciplinary study on bypassed oil distribution in this field, a new horizontal well drilling program was launched in 2012. The study team highlighted challenges in identifying the oil water contact (OWC) while placing the trajectory within a very small target window close to the roof that the program needs to be overcome. Off a detailed technology review, advance azimuthal LWD, with the ability to map the distance to the multiple boundaries such as the OWC, the top and bottom of the reservoir structure in the remaining oil column, was selected as the fit-for-purpose application and to enhanced reservoir understanding. In combination, rotary steerable drilling system (RSS) was selected to improve drilling efficiency and deliver smooth trajectory control.This new approach using innovative azimuthal LWD technology implementation proved value in its utility by achieving the ultimate objective of drilling productive horizontal wells in QHD oilfield. The application reduced drilling cost, avoided unnecessary trajectory adjustments and kept the lateral trajectory within a very small target window of 1m to 1.5m close to the reservoir cap. Production from these horizontal wells surpassed production by 31% with only 4% water cut. The integrated solution of innovative LWD, well placement and RSS optimized this mature oilfiled development. The authors believe this approach and techniques could effectively address other similar mature oilfields development.