What does wine represent in the Jewish Passover meal?

The red wine at the seder symbolises HaShem's four statements of redemption in the Torah:

1. "I took you out"

2. "I rescued you"

3. "I liberated you"

4. "I took you to Me for a people"

The wine represents redemption while the colour of the red wine reminds us of the blood of the children killed for the Pharaoh.

Please see the related link for an explanation of the symbolism behind all the foods eaten at the seder.