Abstract:

In order to ensure the bactericidal efficacy of sodium hypochlorite (NaClO) solution during the recycling use, the bactericidal effect of NaClO on processed fruits and vegetables was explored. In addition, the effect of fruit or vegetable juice on oxidation/reduction potential (ORP) of NaClO solution was also investigated. Results indicated that 1 kg of cucumber slices could lead to a sharp drop in ORP and the active chlorine content in NaClO solution because of the juice osmosis. However, uncut pak choi had less effect on ORP of NaClO solution, and the ORP value of NaClO solution was still 600 mV when the amount of treated pak choi was 9 kg. The ORP curve between NaClO solution and vegetable juices exhibited an opposite“ S” in shape. According to Boltzman equation and isobetic point theory, NaClO solution lost the bactericidal efficacy at the ORP value of 600 mV and new disinfectants should be added to improve the disinfection potential.

Key words: sodium hypochlorite, oxidation/reduction potential, fresh cut vegetable, bactericidal efficacy