Ingredients

For ginger syrup:

1 1/2 cups water

1 cup sugar

1 cup thinly sliced unpeeled fresh ginger (1/4 lb; from two 5-inch-long pieces.

For punch:

3 cups unsweetened pineapple juice, chilled

1/4 cup fresh lemon juice (3-5 lemons)

1/4 cup fresh lime juice (4-6 limes)

3 cups sparkling water, chilled

4 cups ice cubes

Garnish: lemon and lime slices

Special equipment: a small punch bowl or pitcher

Preparation

Make ginger syrup: Bring water, sugar, and ginger to boil in a 1- to 1 1/2-quart saucepan, stirring until sugar is dissolved. Simmer, uncovered, stirring occasionally, 10 minutes, then remove from heat and steep, uncovered, 15 minutes. Pour syrup trough a sieve into a bowl, discarding ginger. Chill, covered, until cold, about 2 hours. Make punch: Stir together ginger syrup and fruit juices in a punch bowl or pitcher. Stir in sparking water and ice. Cook’s note: Ginger syrup keeps, covered and chilled, 2 weeks.