What the cat died of?

"Back in the day" as they say - never telling us which day; "the old folk" would "Tickle" their Taties to see how the tubers were shaping up, without losing a top by digging it up.
I've just done similar to the Oca crop, on account of only having three and not wanting to prematurely dig one.
Supposedly:-
"Eaten raw, the oca tubers have a slightly lemony taste, which becomes more nutty during cooking. The tubers also lose their pink/red colour when cooked and turn cream instead. Oca can be cooked in the same way as potatoes and is perfect for adding to soups and stews."  
I halved and tasted the smallest; I didn't detect a significant lemony taste, apparently attributed to a small% of oxalic acid.
Not a meal of course, but I'll boil the other two out of curiosity.