My blue butterfly pea flower lemonade has a lighter hue than what you’ll see here and here. These recipes state to steep the flowers in boiling water first to allow the blue pigment to be extracted before adding the juice of a lemon and transform the blue tea purple.
I prepared mine in a different order: squeeze the juice of a lemon into a glass first, followed by adding ice cubes that has been frozen with the flowers inside each of them. This method suits me better since I prefer my lemonade really sour with little dilution. By the time all the ice cubes has melted, at least the drink still stay tasting like lemonade.
I started freezing these blue flowers in my ice cube tray when I ran out of ideas what to do with them as they continue to bloom. I have since brewed them as hot blue tea, dye a cotton hankerchief into a lightest shade of blue (the color has since faded after a few washing), and conducted a self-learning calligraphy lesson in, you guessed it, blue ink.
This is a great way to preserve the blooms and make pretty drinks. If you let these ice cubes melt on counter, you will get a puddle of blue ink which you can subsequently use for your favorite crafting ideas with blue pigment.
Back to my lemonade, as the ice cubes started to melt, the color of the drink slowly turned pink. It’s so perfect for the warm day!
For the curious ones, this explains the science behind.
MONO and CO 