The wife’s craving gives me an opportunity to discuss a topic that baffled me for years: tapioca. I was told that tapioca was made from the same root that yucca came from, but that seemed impossible. Those little translucent pearls seemed to have nothing in common with the big, fibrous tubers that were so easily turned into South America yucca fries. It was only a few years ago that I came to understand that the cassava root (also called manioc and/or yucca) is actually a multi-purpose starch, one that can be eaten as-is or processed into different forms, not unlike wheat.
The big difference between wheat and cassava root is that cassava root in its natural state is toxic. It contains the same kinds of cyanogenic compounds that can be found in the pits of stone fruits like apricots and peaches. These are of course the cassava plant’s built-in defense mechanisms, designed to prevent pesky critters like humans from pilfering its underground water reserves. Chew them and the cassava’s enzymes conveniently prune the long cyanogen molecules down into hydrogen cyanide, a compound whose bitter flavor starts as a warning (put the tuber down and back away), but ends as a poison (you leave me no option but to use deadly force), destroying vital energy-liberating enzymes in the animal’s gut.
Not all cassava roots are equally poisonous. So-called “sweet” cassava only has cyanogens in its skin. These are the ones you generally find in supermarkets. “Bitter” varieties are the more common, better producing kinds which are suffused with cyanogens to their very core. These must be processed before they can be eaten. That is: shredded, soaked and pressed, something native South Americans have been doing for millennia. It takes a little more work to get to tapioca, but more on that later. I need to take little Josephine to day care.