In print the Finnish name lapin eukon lemmenjuoma is almost without exception bowdlerized. Common forms include the simplified lapin lemmenjuoma (lapp lovepotion) and the incomprehensible lapin äidin lemmenjuoma and lapin isoäidin lemmenjuoma (lappish mothers lovepotion and lappish grandmothers lovepotion; respectively). No-one speaking about the real stuff will use these euphemisms though.
In the written word the recipe is also usually watered down. The amount of work teasing the sugar in etc. is not suitable for these timepressed days. And if it is to be used as a party drink, rather than an intimate tipple, the costs of providing enough raw material and bottles to produce significant amounts of finished produce may well be prohibitive. Nevertheless, if one only uses one cup of blueberries and sugar to a liter of water, rather than a heady drink the result will be more of a refreshing drink much closer to lemonade; and the gains from a purely catalytic process is totally wasted (yeast slows down when the alcoholcontent rises but the catalytic process is only limited by raw material).
It is fermented out of blueberries without yeast. The process uses the berries natural enzyme for its fermentation. Since the method requires sunlight to enable the catalyst to work its "magic", and is thus dependent on the capricious weather, it has been deemed unsuitable for industrial production.
To make lappish hags lovepotion you pack a clear glass bottle loosely with the unbroken blueberries nearly up to its neck. Adding as much sugar as you can fit into the interstices is preferred. Add water right up to the top. Then leave it for as long as it takes for the sugar to completely melt, then add more sugar to again bring the waterlevel to the top. Wait again, and add more sugar, repeating the process as often as necessary. Cork the bottle (without leaving air), a screwcap will do, as no pressure will build up. and place the bottle in a place where you think it will get the most ample sunshine. Leave for a month or so, adjusting for how sunny the weather has been. Strain the berries out and enjoy!
The color is a bright scintillating red, and the taste (when weather has favored) a balanced, uncloyingly sweet but fragile fruity flavour more reminscent of raspberry than blueberry.
Some establisments will also offer cocktails alluding to lappish hags lovepotion, usually containing blueberry syrup as one of the ingredients. These are generally very difficult to recommend, and definitely nothing like the real thing.