Te Radar: Don't stop the rot

All that rots is not bad - Te Radar makes the case for fermentation. Photo / Supplied

One man's putrid is another man's delicious.

The Greenland shark has no urinary tract. As a result it's forced to secrete urine through its skin, meaning the shark's flesh is highly toxic. When eaten fresh it can cause neurological issues similar to drunkenness, which could be good, and the vomiting of blood, which isn't.

But at some point in the past an innovative Icelander decided that if they gutted the shark, buried it in gravel, piled heavy rocks on top of it to press the moisture out, and left it to rot for several weeks before digging it up and hanging it in a shed for months to dry, it might become a tasty treat. They were right. Sort of.

The result is called Hakarl, and due to its taste and aroma it is widely believed to be one of the most disgusting foods in the world by everyone other than Icelanders who are immensely proud of their delicacy.

Hakarl is a brilliant example of human inventiveness with food and our mastery of fermentation; the process of using bacteria, yeast, or mould to modify food for taste, preservation or safety.

Put simply, fermentation is "controlled spoilage." Aficionados describe it more poetically as the "creative space between fresh and rotten." For some cultures that space can be a lot wider than many might be comfortable with.

Essentially microbes eat the food before we do, predigesting it for us. This is a boon for those of us who are too lazy to do our own digesting.

In an age when we are inundated by advertisements creating an almost pathological terror about bacteria and mould, it would mortify many if they knew that up to a third of all food we consume is created by fermentation.

It's one of the oldest processes known to man, and has brought us the gastronomic pleasures of such staples as bread, cheese, pickles, yoghurt, sauerkraut, miso, salami, wine, beer, chocolate and coffee. These are only a tiny portion of the delicacies created by the interaction of other life forms, all busily eating, procreating and dying in and on our food.

I'd never thought much about it until I met self described fermentation fetishist Sander Katz. His passion for the subject ranges from simple lessons on pickling produce, to musings on fermentation's place in the politics of food sovereignty and global energy efficiency.

As he pointed out, sauerkraut requires only a jar, water, cabbage, salt and time. One fermenting fan at the workshop remarked that he felt that his sauerkraut had a fuller flavour if it was mixed by the hands of several people, rather than doing it all by himself. He attributed it to the wider variety of bacteria on the hands of the mixers. This belief is a delightful antithesis to the modern food industry, obsessed as it is with sterility, although I couldn't help staring uncomfortably at his hands for ages.

But for people who want to farm and who are a little work shy what could be better than having colonies of bacteria busy creating food. Instead of the lowing of cows, or the bleating of sheep, you can lull yourself to sleep with the bubbling and gurgling of containers of gently fermenting food and beverages.

You can even capture your own "wild" yeast for bread or beer making. While the technique for the hunt is as simple as leaving wet dough on the windowsill what makes it a little worrying is the knowledge that there is wild yeast just drifting about that can be caught. It is almost as terrifying as the thought of being presented with a plate of Harkal.

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