Armaghan Saeedi - M.Sc., Islamic Azad University, Varamin- Pishva Branch, Department of Industrial Engineering & Food
Simin Asadolahi - Faculty member, Islamic Azad University, Varamin- Pishva Branch, Food Industry Engineering and Sciences Group
Hashem Mostafapournahid - B.Sc., Islamic Azad University,Tehran- Qods County,Departmen of Agriculture & Food Science

The aim of this research was to compare the antibacterial effect of two kinds of essential oils, peppermint and orange, on the main pathogen of drinking water; with omitting the process chlor and ozone in preparing drinking water. So, the density collection serials of :1:1, :1:1, :1:1, :1:1, :1::1, :13:1 and :1::1 in pipes containing : ml distilled water was prepared. The herbal essential oils are volatile and oily and their degree of being solved in water is less; to eliminate this defect, 01 micro liters of the essential oils was solved in a solvent containing :4 micro liter Ethanol 4:০ and : micro liter tween :1. On the base of achieved results, orange essential oil showed the prevention effect on ::th day and in densities and was known as the best substance.

Peppermint essential oil; Orange essential oil; Antimicrobial properties; drinking water