Prickly Palusami @ Pasifika 2011

I have had very little to do with Polynesian cuisine so far, so I was excited to discover a couple of weeks ago that the Pasifika Festival was on.  With lots of stalls and performance areas clumped in "villages" around the beautiful Western Springs park, there was plenty of opportunity to try new foods and generally have a great day.

One of the "villages" by the lakeside

For me, practically everything was a novelty—from the 'ota 'ika (raw fish salad in coconut cream), pork buns and pani popo (buns in coconut milk sauce) which my friends went for—to the curry on cassava, pisua (a tapioca dessert which tasted of butterscotch) and pani keke ("banana pancake", more like deep-fried spherical donuts to me) which I tried—to the curiously-named items that we giggled at but did not manage to sample, like poke (Hawaiian raw fish salad) and 'otai (fruit drink with coconut milk).  Sapasui (chop suey mainly made with Chinese vermicelli, a.k.a. bean thread or glass noodles) and watermelon icecream also seemed to be very popular.

Watermelon icecream

What was for me the most memorable dish though, was the palusami (coconut cream and onions wrapped in taro leaves).  I was particularly curious about this as I had just read Jeffrey Steingarten's terrible reaction to eating food served on a raw taro leaf garnish in his book It Must Have Been Something I Ate.  I had also tried patra or alu vadi (taro leaf rolls) at one of my favourite Indian restaurants, Ras Vatika, which I enjoyed.  I simply needed to try taro leaves in another delicacy.

My first reaction was that it was delicious.  With coconut cream and savoury onions, the spinach-like packet was very tasty indeed.  As I ate though, I began to feel a prickling sensation in my mouth.  By the time I got to halfway through the palusami, it was actually painful.  Fortunately, unlike Steingarten, my breathing was not affected; but suffice it to say, I had difficulty convincing anyone else to try palusami from another stall.

Half-eaten palusami

Is this feeling normal from a prepared dish?  Is it bad for you?  Everything I have read suggested it was perfectly safe to eat cooked taro leaves, and my palusami certainly looked thoroughly cooked.  The acridity in raw taro is caused by raphides, or needle-like crystals, of calcium oxalate, which are located near stores of protein-eating enzymes, creating what Harold McGee calls "poison-tipped darts" in his book On Food and Cooking: The Science and Lore of the Kitchen.  According to him, cooking breaks down the plant's defence system by "denaturing the enzymes and dissolving the crystals."  Could it be that my palusami simply wasn't cooked enough, even though it looked limp?

I haven't completely worked it out yet, but from what I gather from the Taro Wikispaces page, it's not so much the insoluble oxalates such as calcium oxalate which you should be worried about.  These pass through your system, while the soluble oxalates (which also exist in taro leaves) are easily absorbed and can lead to kidney stones.  You want to boil your leaves (or apply some other moist heat treatment) and throw away the water to reduce the soluble oxalate levels.  You can also eat your taro leaves with a calcium-rich food like milk so that insoluble calcium oxalate salts get formed, thus reducing oxalate absorption.

After reading the sections on Elephant Ear (a close relative of taro, with large leaves) and Taro in the book Poisonous Plants of Paradise: First Aid and Medical Treatment of Injuries from Hawaii's Plants by Susan Scott and Craig Thomas, it occurs to me that I may have eaten a specimen of the plant that simply cannot be made edible by any amount of cooking.  Perhaps cooks would do well to heed the advice shared on Elaichi et Cetera: "A tip from Vee of Past, Present and Me: break the stem of an arbi [a.k.a. taro] leaf you intend to use, rub the juice on your inner wrist and count to ten; if it stings, the oxylate concentration is too high. Don’t use them."