Can whole almonds be substituted for blanched & slivered, or would the result be bitterness from the skins?

Thanks everyone!

I do not mind the skin of almonds for savory dishes or just munching on them, but in a cake, where they are used instead of flour they should be delicate and light in color.
Thanks’ everyone for excellent answers.

Beside the bitterness, which some taste, especially in this much density, you'd be making a very different, more rustic cake. Blanched almonds have a much more delicate flavor.

It is very easy to take the skins off your almonds, and would be worth doing so. Just soak them in water for a couple of hours and the skins will pop right off. Unlike sdebrango, I taste the bitterness of almond skins.

I'm going to jump in here, maybe Kukla will see this and have an answer for you but in my opinion you certainly can use whole almonds. I don't really notice an appreciable amount of bitterness from the skins and with the fruit and sugar I think that it would be fine. If you don't have access to blanched skinless almonds then I think using the whole almond would work just fine.