Why did my oatmeal and raisin cookies end up tasting soapy? I've made oatmeal cookies twice, and both times they have ended up tasting &quot;soapy&quot; and a touch bitter - the first time really strongly, the second less so, but still badly enough that I have to throw them away.
The details of the first attempt are lost to time, but the second time I used this recipe. I think I followed it pretty accurately.
The only theories I have right now are:

The bicarbonate of soda has a naturally soapy flavour (does it?), and I didn't fully finish cooking the cookies (I like them quite chewy - they definitely had a tan on top but probably could have had at least another 2-3 minutes in the oven before burning I suspect). But I baked them for around 15 minutes, more than the recipe anyway.

The oats were a little old (the packet was probably about two months old), and maybe they'd gone bad? But they looked fine, and when I cooked some not that long ago for breakfast, they seemed fine.


Do either of these seem plausible, or is there another possible explanation?
Soap is effectively a base (eg baking soda) reacted with a fat (eg oil). Also, heating baking soda can cause it to convert into sodium carbonate, which is a much stronger base.
I would suspect you're on the mark with suspecting the baking soda. The recipe calls for only a quarter of a teaspoon, so it would be very easy too add too much.