Any bitterness in your Brazilian lemonade is most likely due to the white pith present in the skin. Luckily, there are a few ways to combat this: - Once your limes are quartered, removing as much visible pith as possible before blending will cut down on the bitter flavor. - Make sure to only blitz the ingredients as much as needed. A few pulses, equalling about 15-20 seconds, will do the trick. Excessive blending will cause the bitter-tasting chemicals in the peels to continue releasing. If all else fails, and your limonada is still too bitter, try this:  - Zest the limes and set the zest aside. - Remove and discard the remaining peels and pith.  - Put the peeled limes and zest into the blender and proceed with the recipe.