Combine chilled pineapple juice and orange juice; add aromatic bitters.
Divide among 4 chilled glasses.
Tip each glass and pour ginger ale down side to fill.
Top each serving with a scoop of pineapple sherbet.
If desired, thread fresh fruit (strawberries, melon balls) on glass straws for kabob stirrers.
Garnish with a sprig of fresh mint.