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An in-house method, employing magnetic stirring-assisted aqueous extraction combined with gas chromatography-flame ionization detector, for determination of ethanol in different foods and beverages was validated according to the ISO/IEC 17025 standard. Validation parameters, including selectivity, method limits of detection (approx. 0.006 mg/g) and quantification (approx. 0.02 mg/g), linearity (R2 of >0.999), trueness (relative biases of

Rhus verniciflua Stokes (RVS), an herbal medicine found in East Asia, was extracted and further fractionated to investigate its antioxidant capacity and neuroprotective effects. The RVS ethyl acetate (EtOAc) fraction had the highest level of total phenolics and antioxidant capacity among all solvent fractions tested. Pretreatment of PC-12 cells with the EtOAc fraction effectively attenuated H2O2-induced oxidative damage. Furthermore, the EtOAc fraction significantly attenuated caspase-3 activity, resulting in inhibition of H2O2-induced apoptosis. We identified and quantified fustin, sulfuretin, and butein in the EtOAc fraction using accurate mass quadrupole time-of-flight mass spectrometry and reversed-phase high-performance liquid chromatography. The intracellular antioxidant capacity and superoxide dismutase (SOD) activity were significantly increased in PC-12 cells treated with the EtOAc fraction and with individual flavonoids. When cells were pretreated with the EtOAc fraction or individual flavonoids and then co-incubated with diethyldithiocarbamic acid (an inhibitor of SOD activity), cell viability against H2O2-induced oxidative stress was attenuated. These results suggest that the RVS EtOAc fraction and its flavonoid constituents protect PC-12 cells against H2O2-induced neurotoxicity through their antioxidant properties.

Ascertaining the authenticity of the unrefined sesame oil presents an ongoing challenge. Here, the determination of 2-propenal was performed by headspace solid-phase microextraction (HS-SPME) under mild temperature coupled to gas chromatography with time-of-flight mass spectrometry, enabling the detection of adulteration of unrefined sesame oil with refined corn or soybean oil. Employing this coupled technique, 2-propenal was detected in all tested refined corn and soybean oils but not in any of the tested unrefined sesame oil samples. Using response surface methodology, the optimum extraction temperature, equilibrium time, and extraction time for the HS-SPME analysis of 2-propenal using carboxen/polydimethylsiloxane fiber were determined to be 55°C, 15 min, and 15 min, respectively, for refined corn oil and 55°C, 25 min, and 15 min, respectively, for refined soybean oil. Under these optimized conditions, the adulteration of unrefined sesame oil with refined corn or soybean oils (1–5%) was successfully detected. The detection and quantification limits of 2-propenal were found to be in the range of 0.008–0.010 and 0.023–0.031 µg mL−1, respectively. The overall results demonstrate the potential of this novel method for the authentication of unrefined sesame oil.

The growth of epiphytic bacteria (aerobic mesophilic bacteria or Pseudomonas spp.) on kale was modeled isothermally and validated under dynamic storage temperatures. Each bacterial count on kale stored at isothermal conditions (4 to 25 °C) was recorded. The results show that maximum growth rate (μmax ) of both epiphytic bacteria increased and lag time (λ) decreased with increasing temperature (P 0.97), whereas lower R(2) > 0.86 and R(2) > 0.87 was observed for the λ and Nmax , respectively. The overall predictions of both epiphytic bacterial growths under nonisothermal conditions with temperature abuse of 15 °C agreed with the observed data, whereas those with temperature abuse of 25 °C were greatly overestimated. The appropriate parameter q0 (physiological state of cells), therefore, was adjusted by a trial and error to fit the model. This study demonstrates that the developed model was able to predict accurately epiphytic bacterial growth on kale stored under nonisothermal conditions particularly those with low temperature abuse of 15 °C.

Herein, we report the development of a matrix solid-phase dispersion (MSPD) extraction method for determining flavonoids (orientin, isoorientin, vitexin, isovitexin, quercetin-3-O-robinobioside, and rutin) from common buckwheat sprouts (CBS) and Tartary buckwheat sprouts (TBS) by high-performance liquid chromatography (HPLC-PDA). Key parameters, including sorbent type, sorbent-to-sample ratio, extraction solvent (type, concentration, and volume), and extraction time were optimized. The optimized MSPD extraction conditions include a C18-sorbent/sample ratio of 2:1 (w/w) [total mixture weight = 100 mg] and 10 min of static extraction with 5 mL of 80% ethanol. The optimized MSPD extraction method was satisfactorily validated for all target flavonoids from both CBS and TBS. The validated method was also more effective and efficient compared to ultrasound- and homogenate-assisted extraction techniques. The overall results show that the MSPD extraction method developed in this study is a simple, effective, and efficient technique for the HPLC analysis of flavonoids in CBS and TBS.

In this study, deep eutectic solvents (DESs) coupled with ultrasound-assisted extraction (UAE) were evaluated and optimized for the extraction of major flavonoids from common buckwheat sprouts. Initially, 18 different choline chloride (CC)-based DESs were evaluated as potential extraction solvents, and 80% CCTG (CC-based DES composed of triethylene glycol and 20 vol% water) extracted significantly higher (p 0.05) amounts of flavonoids than other DESs studied. The extraction efficiency of 80% CCTG was even higher (p 0.05) than that of methanol for the extraction of vitexin and quercetin-3-O-robinobioside. Procedure using 80% CCTG and UAE were optimized; an extraction temperature of 56 °C and extraction time of 40 min were considered optimal. The optimized extraction procedure was reliable and efficient for the extraction of major flavonoids from common buckwheat sprouts. In addition, flavonoids could be efficiently recovered from DES extracts with high recovery yields (97%) by using a C18 solid-phase extraction.

Microbial spoilage is a complex event to which different bacterial populations and metabolites can contribute depending on the storage conditions. This study explored the evolution of spoilage and related volatile organic compounds (VOCs) in chilled beef under air and vacuum packaging (VP). The results suggested that different storage conditions affected changes in bacterial communities and metabolites in beef and consequently affected the odor properties of the stored beef, thereby leading to spoilage. Bacterial species belonging to Pseudomonadaceae (Pseudomonas spp.) and lactic acid bacteria (Lactobacillus sp.) dominated the bacterial communities in beef stored under air and VP, respectively, with several VOCs associated with off-odors of the stored beef and most likely produced by both bacteria. Our results suggested several microbial VOCs that could be used as potential spoilage indicators, including acetic acid, butanoic acid, and 2-butanone in VP-stored beef and 3-methylbutan-1-ol, ethyl acetate, acetoin, 2-butanone, and diacetyl in air-stored beef. These findings might provide valuable information regarding the quality monitoring of beef during storage.

This study evaluated the efficacy of the individual treatments (slightly acidic electrolyzed water [SAcEW] or fumaric acid [FA]) and their combination to reduce Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, and Salmonella Typhimurium in fresh pork as well as to study the shelf life and sensory quality (color, odor, and texture) of pork during storage at 4 and 10 °C. The inoculated pork samples (10 g) were dipped for 3 min in each treatment (tap water [TW], SAcEW, strong acidic electrolyzed water [StAEW], 0.5% FA, or SAcEW + 0.5% FA) with or without mild heat (40 °C). Decontamination of fresh pork with SAcEW +0.5% FA at 40 °C for 3 min showed greater bactericidal effect compared to other treatments, which significantly (P

This study was conducted to investigate the disinfection efficacy of hurdle treatments (thermosonication plus slightly acidic electrolyzed water [SAcEW]) and to develop a model for describing the effect of storage temperatures (4, 10, 15, 20, 25, 30, and 35°C) on the growth of Escherichia coli O157:H7 on fresh-cut kale treated with or without (control) thermosonication combined with SAcEW. The hurdle treatments of thermosonication plus SAcEW had strong bactericidal effects against E. coli O157:H7 on kale, with approximately 3.3-log reductions. A modified Gompertz model was used to describe growth parameters such as specific growth rate (SGR) and lag time (LT) as a function of storage temperature, with high coefficients of determination (R(2)0.98). SGR increased and LT declined with rising temperatures in all samples. A significant difference was found between the SGR values obtained from treated and untreated samples. Secondary models were established for SGR and LT to evaluate the effects of storage temperature on the growth kinetics of E. coli O157:H7 in treated and untreated kale. Statistical evaluation was carried out to validate the performance of the developed models, based on the additional experimental data not used for the model development. The validation step indicated that the overall predictions were inside the acceptable prediction zone and had lower standard errors, indicating that this new growth model can be used to assess the risk of E. coli O157:H7 contamination on kale.

An analytical method involving QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation, followed by LC-MS/MS and GC-MS/MS was developed and validated for the determination of 60 pesticides in eggs. Recoveries of 70-120% were achieved for selected pesticides and relative standard deviations20% were obtained for most analytes at three concentrations. The limit of quantification was10 µg kg

Volatile organic compounds (VOCs) associated with spoilage are attracting the attention as potential markers for monitoring meat quality. The objective of the present study was to evaluate the use of spoilage-associated VOCs as marker compounds for the assessment of beef spoilage during storage at 4 °C in air and when vacuum packed. We used headspace solid-phase microextraction coupled with gas chromatography time-of-flight mass spectrometry to determine the levels of VOCs formed during storage. Correlation analysis and multivariate analyses (principal component and hierarchical clustering analysis) were used to select several VOCs that most contribute to sensory changes, and to classify beef samples based on the degree of spoilage assessed by sensory panelists, respectively. Levels of acetic acid, ethanol, 2-methylbutan-1-ol, 3-methylbutan-1-ol, 2,3-butanediol, 2-butanone, diacetyl, 2-heptanone, 3-octanone, and acetoin significantly (p

The growth of epiphytic bacteria (aerobic mesophilic bacteria or Pseudomonas spp.) on kale was modeled isothermally and validated under dynamic storage temperatures. Each bacterial count on kale stored at isothermal conditions (4 to 25 °C) was recorded. The results show that maximum growth rate (μmax ) of both epiphytic bacteria increased and lag time (λ) decreased with increasing temperature (P0.05). The maximum population density (Nmax ) of Pseudomonas spp. was significantly greater than that of aerobic mesophilic bacteria, particularly in treated samples and/or at 4 and 10 °C (P0.05). The relationship between μmax of both epiphytic bacteria and temperature was linear (R(2)0.97), whereas lower R(2)0.86 and R(2)0.87 was observed for the λ and Nmax , respectively. The overall predictions of both epiphytic bacterial growths under nonisothermal conditions with temperature abuse of 15 °C agreed with the observed data, whereas those with temperature abuse of 25 °C were greatly overestimated. The appropriate parameter q0 (physiological state of cells), therefore, was adjusted by a trial and error to fit the model. This study demonstrates that the developed model was able to predict accurately epiphytic bacterial growth on kale stored under nonisothermal conditions particularly those with low temperature abuse of 15 °C.

Recent Staphylococcus aureus outbreaks linked to meat and poultry products underscore the importance of understanding the growth kinetics of S. aureus in these products at different temperatures. Raw pork, ham, and sausage (each 10 ± 0.3 g) were inoculated with a three-strain cocktail of S. aureus, resulting in an initial level of ca. 3 log CFU/g. Samples were stored isothermally at 10, 15, 20, 25, 30, 35, and 40°C, and S. aureus was enumerated at appropriate time intervals. The square root model was developed using experimental data collected from S. aureus grown on all samples (where data from raw pork, ham, and sausage were combined) so as to describe the growth rate of S. aureus as a function of temperature. The model was then compared with models for S. aureus growth on each individual sample in the experiments (raw pork, ham, or sausage) and the S. aureus ComBase models, as well as models for the growth of different types of pathogens (S. aureus, Escherichia coli O157:H7, Clostridium perfringens, Salmonella serovars, and Salmonella Typhimurium) on various types of meat and poultry products. The results show that the S. aureus model developed here based on the pooled data from all three pork products seems suitable for the prediction of S. aureus growth on different pork products under isothermal conditions from 10 to 25°C, as well as for S. aureus growth on different meat and poultry products at higher temperatures between 20 and 35°C. Regardless of some high deviations observed at temperatures between 25 and 40°C, the developed model still seems suitable to predict the growth of other pathogens on different types of meat and poultry products over the temperature ranges used here, especially for E. coli O157:H7 and Salmonella Typhimurium. The developed model, therefore, may be useful for estimating the effects of storage temperature on the behavior of pathogens in different meat and poultry products and for microbial risk assessments evaluating meat safety.

This study evaluated the efficacy of individual treatments (thermosonication [TS+DW] and slightly acidic electrolyzed water [SAcEW]) and their combination on reducing Escherichia coli O157:H7, Listeria monocytogenes, and spoilage microorganisms (total bacterial counts [TBC], Enterobacteriaceae, Pseudomonas spp., and yeast and mold counts [YMC]) on fresh-cut kale. For comparison, the antimicrobial efficacies of sodium chlorite (SC; 100 mg/L) and sodium hypochlorite (SH; 100 mg/L) were also evaluated. Each 10 g sample of kale leaves was inoculated to contain approximately 6 log CFU/g of E. coli O157:H7 or L. monocytogenes. Each inoculated or uninoculated samples was then dip treated with deionized water (DW; control), TS+DW, and SAcEW at various treatment conditions (temperature, physicochemical properties, and time) to assess the efficacy of each individual treatment. The efficacy of TS+DW or SAcEW was enhanced at 40 °C for 3 min, with an acoustic energy density of 400 W/L for TS+DW and available chlorine concentration of 5 mg/L for SAcEW. At 40 °C for 3 min, combined treatment of thermosonication 400 W/L and SAcEW 5 mg/L (TS+SAcEW) was more effective in reducing microorganisms compared to the individual treatments (SAcEW, SC, SH, and TS+DW) and combined treatments (TS+SC and TS+SH), which significantly (P0.05) reduced E. coli O157:H7, L. monocytogenes, TBC, Enterobacteriaceae, Pseudomonas spp., and YMC by 3.32, 3.11, 3.97, 3.66, 3.62, and3.24 log CFU/g, respectively. The results suggest that the combined treatment of TS+SAcEW has the potential as a decontamination process in fresh-cut industry.

Aims: To evaluate synergetic effect of slight acidic electrolysed water (SAEW)and fumaric acid (FA) on inactivation of total viable count (TVC) andStaphylococcus aureus, Listeria monocytogenes, Escherichia coli O157:H7 andSalmonella Typhimurium in fresh beef and to study shelf life and sensoryquality of beef.Methods and Results: Inoculated samples was dipped for 1, 3 and 5 min andimmersed at 25, 40 and 60°C in SAEW, strong acidic electrolysed water(StAEW) and SAWE + FA. Treated meat was air-packaged and stored at 4 or10°C. During storage, sampling was performed at 2-day intervals formicrobiological and sensory changes. TVC was decontaminated at 40°C for3 min by more than 3 70 log CFU g 1 , and examined pathogens were reducedby more than 2 60 log CFU g 1 with SAEW + FA treatment. This treatmentprolonged shelf life of beef meat up to 9 and 7 days when stored at 4 and10°C, respectively.Conclusion: The combined treatment of SAEW + FA showed greaterbactericidal effect and prolonged shelf life compared with individualtreatments.Significance and impact of the study: Combined treatment of SAEW and FAcan be a suitable hurdle technology reducing bacteria in fresh beef,substantially enhancing their microbial safety and decreasing pathogens growthduring storage.IntroductionDuring slaughtering and processing of all edible carcasstissues, the meat is subjected to internal and externalcontaminations from a variety of sources. Microbialgrowth is generally confined to the outer surfaces wherebacteria irreversibly bind to. Meats contaminated withListeria monocytogenes, Staphylococcus aureus, Escherichiacoli O157:H7 and Salmonella spp. have been reported asthe causal agents of food-borne diseases (Koohmaraieet al. 2005; Jofre et al. 2008; Perez-Rodriguez et al. 2010).The micro-organisms reach the carcass surface where theypenetrate into deeper layers of the meat. By reducing thisprimal surface contamination and avoiding or limitingthe microbial growth, we can considerably reduce theburden of food-borne diseases and extend shelf life offresh meat (Pipek et al. 2005).Although food-borne pathogens are subjected to physi-cal, chemical and nutritional stress during processing andthe improvements are made in hygienic slaughter pro-cessing, they still persist at high level in raw meat (Abbas-si-Ghozzi et al. 2012; Osaili et al. 2013), rendering theirelimination/inhibition a challenge to processors (Pathaniaet al. 2010). Significant advances have been made indeveloping thermal and nonthermal intervention technol-ogies to reduce food-borne pathogens in meat and meatproduct during the slaughtering process. Innovative tech-nologies are needed that use little heat to preserve the

The efficiency of gamma irradiation (0, 1, 5, 10, 15, 20, and 30 kGy) as a sterilization method of corn samples (30 g) artificially contaminated with Fusarium moniliforme stored at normal condition (25oC with approximate relative humidity (RH) of 55%) and optimal condition (25oC with a controlled RH of 97%) was studied. The results showed that the fungal growth and the amount of fumonisin were decreased as the dose of gamma irradiation increased. Gamma irradiation at 1-5 kGy treatment significantly inhibited the growth of F. moniliforme by 1-2 log reduction on corn samples (P < 0.05). Sublethal effect of gamma irradiation was observed at 10-20 kGy doses after storage, and a complete inactivation required 30 kGy. Fungal growth and fumonisin production increased with higher humidity and longer storage time in all corn samples. This study also demonstrated that there was no strict correlation between fungal growth and fumonisin production. Storage at normal condition significantly resulted in lower growth and fumonisin production of F. moniliforme as compared with those stored at optimal condition (P < 0.05). Gamma irradiation with the dose of ≥ 5 kGy followed by storage at normal condition successfully prolonged the shelf life of irradiated corns, intended for human and animal consumptions, up to 7 weeks.