Effects of different ozone treatments on the storage quality and stability of fresh peeled garlic

In order to understand their impacts on the preservation of fresh garlic, varying concentrations of ozone gas and different storage temperatures were tested for this experiment.

Application of ozone against the larvae of Plodia interpunctella (Hübner) and its impacts on the organoleptic properties of walnuts

One of the most important products grown in Iran is walnut, while it can be threatened by some storage pests. Ozonation process is an environmentally friendly method for killing pest insects. Accordingly, ozone efficacy in the control of a pest species of walnut was assessed in this research. The selected walnut samples were infested with larvae of Plodia interpunctella (Hübner) and then subjected to various combinations of ozone concentrations (3, 4.5, and 6 ppm) and exposure times (20, 30, 40, and 50 min). Following the exposures to the ozone treatments, larval mortality rates and changes to the sensory properties (color, taste, smell, crispness, stiffness, and overall acceptability) of the walnut indicating consumer preference were evaluated. Our results revealed enhanced mortality rates of our pest with an increase in both ozone concentration and exposure time in a way that 99% mortality was recorded at the concentration and exposure time of 6 ppm and 50 min, respectively. The sensory assessments of the samples showed that ozone treatments had no significant impacts on the color, taste, crispness, stiffness, and overall acceptability of the product. Also, few changes were recorded for its smell, which could be improved over time after being exposed to the air. We concluded that application of higher ozone concentrations might provide acceptable levels of pest control for stored walnut with no possibly associated reduced trade-off for their quality attributes.

Evaluation of UVC Radiation and a UVC-Ozone Combination as Fresh Beef Interventions against Shiga Toxin–Producing Escherichia coli, Salmonella, and Listeria monocytogenes and Their Effects on Beef Quality

ABSTRACT This research study was conducted to evaluate treatments with UVC light and a combination of UVC and ozone that have recently received attention from the beef processing industry as antimicrobial interventions that leave no chemical residues on products. The effectiveness of UVC and UVC plus gaseous ozone treatments was evaluated for inactivation of pathogenic bacteria on fresh beef and for any impact on fresh beef quality. Fresh beef tissues were inoculated with cocktails of Shiga toxin–producing Escherichia coli (STEC) strains (serotypes O26, O45, O103, O111, O121, O145, and O157:H7), Salmonella, and Listeria monocytogenes. Inoculated fresh beef tissues were subjected to UVC or UVC-ozone treatments at 106 to 590 mJ/cm2. UVC treatment alone or in combination with ozone reduced populations of STEC, Salmonella, L. monocytogenes, and aerobic bacteria from 0.86 to 1.49, 0.76 to 1.33, 0.5 to 1.14, and 0.64 to 1.23 log CFU, respectively. Gaseous ozone alone reduced populations of E. coli O157:H7, Salmonella, and L. monocytogenes by 0.65, 0.70, and 0.33 log CFU, respectively. Decimal reduction times (D-values) for STEC serotypes, Salmonella, and L. monocytogenes on surfaces of fresh beef indicated that the UVC-ozone treatment was more effective (P ≤ 0.05) than UVC light alone for reducing pathogens on the surface of fresh beef. Exposure to UVC or UVC plus gaseous ozone did not have a deleterious effect on fresh meat color and did not accelerate the formation of oxidative rancidity. These findings suggest that UVC and UVC in combination with gaseous ozone can be useful for enhancing the microbial safety of fresh beef without impairing fresh beef quality. HIGHLIGHTS