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Sesame oil is a high-value edible vegetable oil, and concern about its authenticity has gained much attention for commercial and consumer health reasons. The present study compares the application of triacylglycerols (TAGs), fatty acids, and volatile organic compounds (VOCs) as markers for discriminating pure sesame oils from those adulterated with corn or soybean oils. The profiles of TAGs, fatty acids, and VOCs in oil samples were established by high-performance liquid chromatography-evaporative light scattering detector, gas chromatography (GC)-flame ionization detector, and GC-time-of-flight mass spectrometer, respectively. Data from six TAGs, seven fatty acids, and six VOCs were employed separately to classify oil samples via principal component analysis (PCA). The PCA results indicate that VOCs show much greater promise than TAGs and fatty acids for detecting corn or soybean oil adulteration (approximately 5% w/w content) of sesame oils.

Sanitizing effectiveness of slightly acidic electrolyzed water (SAEW) and fumaric acid (FA) at different dipping temperatures (25–60 °C), times (1–5 min), and concentrations (5–30 ppm for SAEW and 0.125%–0.5% for FA) on pure cultures of two Gram positive pathogens Staphylococcus aureus (SA) and Listeria monocytogenes (LM) and two Gram negative pathogens Escherichia coli O157:H7 (EC) and Salmonella Typhimurium (ST) was evaluated. FA (0.25%) showed the strongest sanitizing effect, demonstrating complete inactivation of EC, ST, and LM, while SA was reduced by 3.95–5.76 log CFU/mL at 25–60 °C, respectively, after 1 min of treatment. For SAEW, the complete inactivation was obtained when available chlorine concentration was increased to 20 ppm at 40 °C for 3 and 5 min. Moreover, Gram positive pathogens have been shown to resist to all treatment trends more than Gram negative pathogens throughout this experiment. Regardless of the different dipping temperatures, concentrations, and times, FA treatment was more effective than treatment with SAEW for reduction of foodborne pathogens. This study demonstrated that application of FA in food systems may be useful as a method for inactivation of foodborne pathogens.

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.

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 O 157: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 (R² > 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. [ABSTRACT FROM AUTHOR]