So I looked at the tub of sunflower lecithin that I bought around July 2021 and it is clear that the color has turned from a much whiter color with hints of yellow to an salted egg yolk-like color with hints of white. Taste-wise it now tastes normal at first, then immediately turns very sour like I've eaten some sour candy then extremely bitter shortly after. A fresh batch of sunflower lecithin would taste slightly bitter, but it was very tolerable and no hints our sourness at all. Odd thing is it hasn't been even 1 year since i've opened it (although not refrigerated and only at room temp) and kept in the pantry cabinet.  Best used by date is still April of next year but it is already inedible for me. My coffee tasted so bad  
Krokan in this case is traditional Swedish wedding cake (the current Swedish king and queen had one, for example), of individual intricate shapes made of a marzipan/almond based mass with sugar and egg whites, that gets piped and baked, then assembled. It’s occasionally (mis-)translated as  e.g. croquembouche, but that’s technically incorrect. The Swedish Wikipedia has an article, so with a bit of google translate you could learn more. The most interesting bit for your research is that the recipe seems to be pretty much identical to the Danish/Norwegian Kransekake (“wreath cake”), just shaped more intricately. That should help when searching for recipes and more information. 