Place the juice, salt and agar flakes in a sauce pan, stir and bring to a boil. Reduce the flame to medium-low and simmer until the flakes have dissolved, about 10 minutes. Slice 3 cups of strawberries and place in a shallow bowl. When the agar flakes have dissolved, remove from the flame and allow to cool slightly before pouring the juice over the strawberries. Refrigerate until gelled, about 1 1/2 hour. This gelled dessert is now called kanten. Place the kanten in a blender with the maple syrup and remaining strawberries. Puree several seconds until creamy. Place the custard in small serving dishes.
Variation: this custard is nice with sliced fresh strawberries or whole blueberries on top. Granola sprinkled on top adds delightful crunch.
Per serving - 89 calories, 0 g fat (2% calories from fat), 0 g protein, 22 g carbohydrate, 2 g fiber, 0 mg cholesterol, 25 mg sodium