نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشکده فیزیک، دانشگاه صنعتی شاهرود
2 گروه علوم و صنایع غذایی، دانشکده کشاورزی، دانشگاه صنعتی شاهرود
کلیدواژهها
عنوان مقاله English
نویسندگان English
Surface Dielectric Barrier Discharge (SDBD) plasma is a novel non-thermal technology capable of generating reactive oxygen and nitrogen species at atmospheric pressure without the need for noble gases within food packaging. In this study, pistachio kernel samples contaminated with Aspergillus flavus spores were treated using SDBD plasma at a voltage of 6.8 kV and frequency of 7.4 kHz for durations of 10, 20, and 30 minutes in air gas inside the packaging. In this research, the reduction in microbial load and the physical characteristics of the plasma, such as current-voltage, were measured, and the plasma power was calculated. Using Optical Emission Spectroscopy (OES), the active species generated in the plasma were investigated. Additionally, the amount of ozone and reactive nitrogen species (NOx) produced was measured, and changes in surface morphology characteristics (FESEM), weight loss, as well as sensory and color parameters were analyzed. Optical Emission Spectroscopy (OES) analysis confirmed the presence of active species such as excited nitrogen (*N₂), hydroxyl radical (•OH), and atomic oxygen (O). The production levels of ozone and reactive nitrogen species (NOx), as well as the weight loss of pistachios, were also measured. Treatment for 30 minutes resulted in a 4-log reduction (99.99%) in the population of A. flavus spores. Field Emission Scanning Electron Microscopy (FESEM) images show complete destruction of the spore cell wall and leakage of spore cytoplasm after 30 minutes of treatment. Sensory evaluation using a 9-point hedonic scale indicated that treatment up to 10 minutes has no adverse effect on the sensory properties of pistachios. However, increasing the treatment time to 20 and 30 minutes, while maintaining the product's odor and taste, leads to a significant decrease in color scores. SDBD technology, with its effective sterilization capability, low cost, and preservation of sensory quality at short treatment times, represents a promising method for enhancing the safety and shelf life of pistachios and other agricultural products.
کلیدواژهها English