an attempt has been made in this study to examine different treatments on shelf life of potato salad. In this study, thermal processing (done 15 to 45 minutes) was done on vegetables of potato salad (including peas and potato and carrot squares). This process was done using hot water, hot acetic acid solution, and combined of hot water- hot acetic acid solution (at first 20 minutes in hot water and then continue the thermal processing in the hot acetic acid solution). After the process, 7 different treatments including lack of practicing good manufacturing hygiene, the use of Rosemary essential oil (%0.01 w/w), the use of Shirazi-thyme essential oil (%0.02w/w), acidification, rapid cooling, vacuum packaging and modified atmosphere packaging (20% carbon dioxide and 80% 14 N 2 ' type="#_x0000_t75"> ) was done on potsto salad samples. Also, three combinated treatments was done. The first combinated treatment (COM1) including Rosemary essential oil, Shirazi-thyme essential oil, acidification, and rapid cooling, the second combined treatment (COM2) including Rosemary essential oil, Shirazi-thyme essential oil, acidification, rapid cooling and vacuum packaging, and the third combined treatment including Rosemary essential oil, Shirazi-thyme essential oil, acidification, rapid cooling, and modified atmosphere packaging (COM3 treatment) was done on potato salad. Prepared treatments along with control sample (without using any treatment) were kept in the refrigerator temperature for 8 weeks. To study the effect of chosen treatments on physico-chemical and microbiological properties of potato salad made from egg free mayonnaise,
