The total time of the electric treatment using 100,150 and 200 volt were 16,6 and 4 minutes respectively. The final temperature was limited to 50ํc, for more damaging the guava tissues. Ohmically heated by AC treatment at 100 volt was more times for final temperature to 50ํC, because of the lowest intensity of voltage, and also the percentage of guava juice yield which was extracted by mechanical extractor from treatment that heated by AC treatment at 100 volt was the best yield showed in Figure 2 related with guava tissue damage. The higher the time of the electric treatment the higher the yield of extracted guava juice. Although the nature of the effects in plant tissues during ohmic heating is rather complex and is not completely understood, it was assumed that the electrical breakdown or electroporation mechanism is dominant.