Inactivation of Listeria monocytogenes on ham and bologna using pectin-based apple, carrot, and hibiscus edible films containing carvacrol and cinnamaldehyde

Edible films can be used as wrapping material on food products to reduce surface contamination. The incorporation of antimicrobials into edible films could serve as an additional barrier against pathogenic and spoilage microorganisms that contaminate food surfaces. The objective of this study was to investigate the antimicrobial effects of carvacrol and cinnamaldehyde, incorporated into apple, carrot, and hibiscus-based edible films against Listeria monocytogenes on contaminated ham and bologna. Ham or bologna samples were inoculated with L. monocytogenes and dried for 30 min, then surface wrapped with edible films containing the antimicrobials at various concentrations. The inoculated, film-wrapped samples were stored at 4 °C. Samples were taken at day 0, 3, and 7 for enumeration of surviving L. monocytogenes by plating on appropriate media. Carvacrol films showed better antimicrobial activity than cinnamaldehyde films. Compared to control films without antimicrobials, films with 3% carvacrol induced 1 to 3, 2 to 3, and 2 to 3 log CFU/g reductions on ham and bologna at day 0, 3, and 7, respectively. Corresponding reductions with 1.5% carvacrol were 0.5 to 1, 1 to 1.5, and 1 to 2 logs, respectively. At day 7, films with 3% cinnamaldehyde reduced L. monocytogenes population by 0.5 to 1.5 and 0.5 to 1.0 logs on ham and bologna, respectively. Inactivation by apple films was greater than that by carrot or hibiscus films. Apple films containing 3% carvacrol reduced L. monocytogenes population on ham by 3 logs CFU/g on day 0 which was 1 to 2 logs greater than that by carrot and hibiscus films. Films were more effective on ham than on bologna. The food industry and consumers could use these films to control surface contamination by pathogenic microorganisms. PRACTICAL APPLICATION: Antimicrobial edible, food-compatible film wraps prepared from apples, carrots, and hibiscus calyces can be used by the food industry to inactivate Listeria monocytogenes on widely consumed ready to eat meat products such as bologna and ham. This study provides a scientific basis for large-scale application of edible fruit- and vegetable-based antimicrobial films on foods to improve microbial food safety.     

Reliability and performance analysis of a high step-up DC–DC converter with a coupled inductor for standalone PV application

ABSTRACT

In view of the major power crisis in fast developing countries, we introduce a quadratic boost converter with coupled inductor for standalone photovoltaic (PV) application, and their respective voltage gain is derived. The features of this proposed topology are studied with the help of steady state analysis and its superiority is proved by comparing it with the existing coupled inductor based topologies. The reliability study is carried out for the proposed topology with its working condition. Also, simulation is performed in the NL5 simulator, and the results are presented. A 40?W prototype of the same is built to showcase the desired output of the proposed converter.     

An intuitive general rank-based correlation coefficient

Correlation analysis is an effective mechanism for studying patterns in data and making predictions. Many interesting discoveries have been made by formulating correlations in seemingly unrelated data. We propose an algorithm to quantify the theory of correlations and to give an intuitive, more accurate correlation coefficient. We propose a predictive metric to calculate correlations between paired values, known as the general rank-based correlation coefficient. It fulfills the five basic criteria of a predictive metric: independence from sample size, value between ?1 and 1, measuring the degree of monotonicity, insensitivity to outliers, and intuitive demonstration. Furthermore, the metric has been validated by performing experiments using a real-time dataset and random number simulations. Mathematical derivations of the proposed equations have also been provided. We have compared it to Spearman’s rank correlation coefficient. The comparison results show that the proposed metric fares better than the existing metric on all the predictive metric criteria.     

Simultaneous Identification of Different Domains of Calpain from Blood and Turkey Meat Samples Using Casein Zymography

The aim of this study was to develop a simple method for simultaneous identification of two different domains of calpains (μ- and m-calpains) in blood and turkey meat samples. The method is based on Tris-based extraction techniques followed by casein zymography detection. The extracts were purified by dialysis, and target compounds were separated on Diethylaminoethyl (DEAE)-Sephacel anion-exchange chromatography. Results indicated that a buffer pH of 6.7 produced optimum extraction efficiency. The separation of calpastatin, μ- and m-calpains on column chromatography was carried out using stepwise elution profiles of 100, 200, and 400 mM NaCl solutions, respectively. Casein zymography study clearly demonstrated the presence of μ- and m-calpains in the crude extracts of breast and blood samples; however, μ-calpain was absent in the thigh sample. Similarly, sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis identified both the calpains from muscle and blood samples, but presence of calpastatin was observed in both the breast and thigh muscle samples only. The activity analysis of purified fractions indicated that both the μ- and m-calpain concentrations were differed significantly (P?<?0.05) amongst breast, thigh and blood samples. Collectively, it was concluded that Tris buffer (pH 6.7) and DEAE-Sephacel column for extraction and separation of μ- and m-calpains and casein zymography and SDS-PAGE detection methods were most suitable for accurate identification of calpains and calpastatin from blood and turkey meat samples.     

Battery energy storage technology for power systems—An overview

The penetration of renewable sources (particularly wind power) in to the power system network has been increasing in the recent years. As a result of this, there have been serious concerns over reliable and satisfactory operation of the power systems. One of the solutions being proposed to improve the reliability and performance of these systems is to integrate energy storage devices into the power system network. Further, in the present deregulated markets these storage devices could also be used to increase the profit margins of wind farm owners and even provide arbitrage. This paper discusses the present status of battery energy storage technology and methods of assessing their economic viability and impact on power system operation. Further, a discussion on the role of battery storage systems of electric hybrid vehicles in power system storage technologies had been made. Finally, the paper suggests a likely future outlook for the battery technologies and the electric hybrid vehicles in the context of power system applications.     

Response Surface Plots for the Behavioral Pattern of Yersinia enterocolitica in Chocolate Milk as Affected by Trans-Cinnamaldehyde, a Spice Essential Oil Constituent

Response surface plots were generated to determine the behavior of a native food isolate of Yersinia enterocolitica CFR 2301 in chocolate milk with added trans-cinnamaldehyde, an active spice essential oil constituent. The minimum inhibitory and bactericidal concentrations (MIC and MBC) for Y. enterocolitica in broth systems were 0.1 and 0.3 μl/ml, respectively, while in chocolate milk, the MBC was 0.9 μl/ml. In chocolate milk devoid of cinnamaldehyde, the culture of Y. enterocolitica CFR 2301 was able to reach risk-causing population levels in 12 h at 30 °C. In the presence of cinnamaldehyde, an inactivation model was generated for the behavior of Y. enterocolitica in chocolate milk, which revealed that, irrespective of initial inoculum levels, the death time (D _T ) was primarily influenced by trans-cinnamaldehyde concentrations and incubation temperatures. The death times were found to decrease with higher cinnamaldehyde concentrations and incubation temperatures. Validation of the model revealed the adequacy of predictions derived for this inactivation model and potential application of compatible possibility to develop food formulations with inhibitory principles.     

Rhodium‐Catalyzed Asymmetric Allenylation of Sulfonylimines and Application to the Stereospecific Allylic Allenylation

The rhodium‐catalyzed asymmetric allenylation of sulfonylimines is disclosed providing silyl homoallenylamide products in up to 99:1 er. Through subsequent activation of the C−N bond of the silyl homoallenyl sulfonamide, palladium‐catalyzed stereospecific allylic allenylation could be achieved giving C−C bond formation with high chirality transfer. The synthetic utility of both the silyl homoallenyl sulfonamides and the silyl homoallenyl malonates as bis(nucleophiles) is demonstrated.

     

Gram scale synthesis of monoclinic VO2 microcrystals by hydrothermal and argon annealing treatment

We report gram scale synthesis of 100% phase fraction of VO₂ (M) monoclinic in powder form with reversible phase transition by combining hydrothermal method and Ar annealing at high temperature. Optimization of single phase VO₂ (M) growth and its phase transition characteristics have been analysed systematically by varying growth parameters such as time, synthesis temperature and post growth annealing conditions. Argon annealing of hydrothermally grown VO₂ powders at 800?°C found to play key role in obtaining VO₂ (M) phase in gram scale with characteristic phase transition temperature of 68?°C. In-situ TEM has been performed to investigate the microstructure and phase change across the annealing temperature. Detailed characterizations have been carried out to correlate the phases, microstructure and transition temperature of VO₂ with respect to growth parameters.