In a large bowl, combine the condensed milk, orange juice concentrate, vanilla, zest, and salt.

In a second large bow, using an electric mixer on high, whip the cold cream until stiff peaks form. (Alternatively, beat the cream in a stand mixer fitted with a whisk.)

Fold about a quarter of the whipped cream into the condensed milk mixture to lighten it. Gently fold in the remaining whipped cream.

Spoon the ice cream into a freezer-safe container or a baking tin lined with plastic wrap or parchment. Place a piece of plastic wrap directly on the surface to prevent ice from forming. Freeze until firm, at least 4 hours, preferably overnight.

To serve, allow to soften at least 10 minutes before scooping, longer if frozen overnight. Alternatively, when you sit down to dinner, place the ice cream in the refrigerator to soften for up to 45 minutes. Return to the freezer immediately after scooping.