On a brisk winter day in early 2019, David Zilber, then head of fermentation at the Copenhagen-based restaurant Noma, placed a batch each of rice, barley and soy sauce koji before a group of students at the University of Gastronomic Sciences in Italy’s Pollenzo. This was the first time Prachet Sancheti, one of his students, had touched and tasted koji.
“I remember being more taken by the soy sauce koji than the rice or barley ones. It was richer in umami, more savoury since it’s protein-heavy. Most people found it slightly strange but I liked nibbling on it,” says Goa-based Sancheti, who now crafts fermented foods under the name Brown Koji Boy.
Koji, which has only recently made inroads into India, is a culture prepared by growing the sporulating mould, Aspergillus oryzae, on cooked grains such as rice or soybeans in warm and humid conditions. The term comes from Japan, though the earliest mention of it can be traced to 300 BCE in China, where it is known as qū. The mould was most successfully domesticated roughly 2,000 years ago in Japan, where several basic seasonings are made with grains inoculated with koji. Think miso pastes, soy sauce, mirin and sake.
When the time is ripe for the mould to flourish, the spores branch out to sprout hyphae that spread their tendrils and discharge a plethora of enzymes that break down starches into simple sugars, proteins into amino acids and fats into lipids, esters and aromatic compounds. The enzymes released by the hyphae are also responsible for koji’s peculiar flavour and fruity, floral smells.
“Koji is magical. The science of it seems so complicated yet it’s so simple. To me, it has made the same impact on food that fire and then salt did. It’s the thing that will take cooking to the next level,” says Bengaluru-based Payal Shah, who goes by the name Kōbo Fermentary on Instagram, describes herself as a shepherd of microbes and is hailed as the “backbone of fermentation in India”.
Koji has the ability to draw out umami, the fifth taste, from anything it touches. This, combined with the simple sugars that are released, gives koji-fermented foods a deep and distinctly rounded flavour—most fermenters put their obsession with the microbial powerhouse down to its transformative nature. Shah illustrates this with her batch of koji-fermented asparagus stalks. “I had saved the woody bits of the asparagus to make stock with. Once the broth was ready, I strained and fermented them with koji. I left it for a year and by the end of it, it tasted like Italian lemons and Parmesan. You can’t make this stuff up.”
Several academic articles have explored the connection between the gut microbiome and mental health, immune responses and even weight loss. Though not all studies are conclusive, it is widely propagated, by modern-day science as well as traditional wisdom, that the bacteria in our gut, strengthened by the bacteria in our food, can have profound effects on our health. “That my gut biome reflects the environment I inhabit, is a powerful idea for me. It allows me to understand the food I prepare and cook for myself in ways that I had not thought of before,” says Ajinkya Dharmapurikar, an IT engineer and fermentation buff, who is based in Pune, Maharashtra.
It doesn’t take long to stumble upon the world of koji once you have been bitten by the fermentation bug. In The Noma Guide To Fermentation, co-authors Zilber and chef René Redzepi write, “It’s nearly impossible not to encounter it, like going to Paris and not seeing the Eiffel Tower.” Since it was difficult to obtain spores earlier, fermentation enthusiasts, such as Sancheti, Shah and Dharmapurikar, have only recently started using the mould on native produce like poha (flattened rice), chickpeas, vatana (dried peas), korgut and jaya varieties of rice, among others.
Dharmapurikar, self-taught like the others mentioned here, warns that koji should be handled with respect. “The fungus is most certainly our friend but its relatives are not (due to the chemicals they produce to decimate microbial competitors). So, one has to be careful. Anything apart from white, yellow-green sporulation that smells fruity spells danger,” he says, adding, “At the end of the day, it’s just an organism that’s trying to survive. It will break down the starches and the proteins. Now, the onus of experimentation is on us.”
This is what makes the fermentation scene in India both ingenious and impressive. For it doesn’t just open doors to Japanese or other East Asian cuisines, making their key flavour players more accessible, but truly harbours the possibility of reimagining decidedly “Indian” dishes.
Brown Koji Boy, which delivers to all major cities in the country, offers an array of condiments with local ingredients as their protagonists—Maa Ki Dal and Black Rice Miso, Kidney Bean Douchi, Chana Dal Amino Sauce, Goan Pesto (made with cashew miso, kokum, curry leaves, garlic and coconut oil) and Smoked Tomato Tamari, among a host of others.
While most of the condiments conjure images of Japanese food—miso soup, ramen, dengaku—in the regular diner’s mind, Sancheti argues for a broadening of their culinary applications. “I recently made khichdi with our spiced chickpea miso. After taking the khichdi off the heat, I stirred in about a tablespoon of miso to elevate its flavour. I also put miso on my dosa and have it with podi. It can be incorporated into most recipes,” he says.
“Working with koji is a bit like learning the rules of the game and then breaking them. It’s not about replicating what someone else is doing. It’s about taking the science of it and then finding ways of making it our own. And it makes sense for us to do it because we have such amazing produce. These choices, this sort of consciousness also allows us to effect changes that are beneficial for our health and the environment,” says Shah.
Damini Ralleigh is a Delhi-based food writer.
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