Pour the orange juice into a small saucepan and simmer over medium heat until reduced to 3/4 cup. Set aside to cool slightly.
In a small bowl, combine the cold water and gelatin. Let stand for 5 minutes to bloom.
In a medium saucepan, combine the reduced orange juice, water, granulated sugar, corn syrup, and orange zest.
Bring the mixture to a gentle boil over medium heat, stirring frequently until the sugar dissolves completely.
Continue cooking until the mixture reaches 212°F to 218°F on a candy thermometer.
Remove the saucepan from the heat and let cool for 1 to 2 minutes.
Strain out the orange zest if desired for a smoother candy.
Whisk the bloomed gelatin into the hot syrup until completely dissolved and smooth.
Stir in the orange extract and lemon juice.
Line an 8-inch square baking pan with parchment paper and lightly grease the parchment.
Pour the mixture into the prepared pan and smooth the top.
Refrigerate for at least 6 hours or until completely firm.
Lift the candy from the pan and cut into 1-inch squares using a lightly oiled knife.
Combine the coating sugar and citric acid in a shallow bowl.
Roll each gumdrop in the sugar mixture until fully coated.
Arrange the gumdrops on a wire rack and let them dry uncovered at room temperature for 24 hours.
Store in an airtight container at room temperature.