Grease the silicone ice cream molds with vegetable oil.
Separate egg whites from egg yolks, weigh 70 g egg whites and put them in a large mixing bowl.
Add citric acid to egg whites and set aside for now.
Puree black currants and pass them through a sieve. Weigh out 150 g of fruit puree and put it in a thick-bottomed saucepan.
Add 280 g sugar, water and agar agar to the fruit puree in the saucepan and mix until homogeneous.
Place the saucepan with the fruit mixture on the stove and bring to a boil over medium heat, stirring.
Beat parallel egg whites with citric acid until foamy, then add 70 g sugar in batches and beat until stiff.
Once the fruit mixture boils, turn the heat down to low and simmer the fruit syrup for 4 minutes, stirring occasionally.
Immediately after boiling, add the hot fruit syrup to the beaten egg whites in a thin stream, continuing to beat it as you go.
After you have stirred the fruit syrup into the beaten egg whites, continue beating it for about 2 minutes more to form a stiff fruit beaten egg whites.
Fill the fruit-zefir mixture quickly (the mixture will set very quickly!) into the piping bag with a large perforated nozzle, squirt it into the silicone ice cream molds, insert the wooden sticks and let it dry at room temperature for about 1 hour.
Carefully lift the zefir lollies out of the silicone molds, spread them on a sheet of baking paper, and let them dry further at room temperature for about 8 hours or overnight.
Slowly melt white chocolate, carefully dip the zefir lollies into it one by one, or pour the chocolate over the lollies with a tablespoon, dripping the excess chocolate off the lollies, and let them dry. Repeat the same with the dark chocolate and the remaining zefir lollies.