Chef-turned-chemist transforms food waste into tasty treats with fungi

Food waste is a pressing global problem, but chef turned chemist Vayu Hill-Maini has found a creative and delicious way to address it using fungi.

Hill-Maini has collaborated with renowned chefs to explore the culinary potential of fungi such as Neurospora intermedia .

For example, this common fungus has been used for centuries in Indonesia to produce oncom, a fermented food made from soy pulp.

This idea of turning waste into food through fermentation piqued Hill-Maini’s interest, leading him to explore its potential for Western food waste.

“The food system is massively wasteful and we urgently need solutions to address this and tackle the challenges it presents for food security and sustainability,” Hill-Maini, a Miller postdoctoral fellow at the University of California, Berkeley, told Interesting Engineering (IE) .

He added: “Fungal fermentation, I think has tremendous power to not only address the critical challenges we are facing but also to create new delicious foods that are good for the planet and for our bodies. I think one day we’ll be able to buy foods that we cherish and love, which happen to be made from otherwise wasted ingredients.”

Genetic analysis of fungi

Oncom comes in two varieties: red and black. The red is generated by fermenting leftover soy pulp from tofu production, whereas the black is made from peanut oil pressings. N. intermedia is known to provide rich flavors to red oncom.

Hill-Maini highlighted that the molecular mechanisms by which fungi convert ingredients into food were not well understood until now.

In this new study, the researchers studied the genetics of Neurospora to learn how it degrades plant waste and produces new tastes.

Genetic studies revealed the presence of two forms of Neurospora: wild strains distributed worldwide and strains that have adapted to live on agricultural waste.

Thanks to its ability to break down cellulose, the domesticated Neurospora strain can turn soy and peanut waste into a flavorful food.

Notably, fungi hold the potential to convert indigestible plant material, such as polysaccharides, into digestible, and nutritious food.

“The fungus readily eats those things and in doing so makes this food and also more of itself, which increases the protein content,” he explained in the pres release. “So you actually have a transformation in the nutritional value. You see a change in the flavor profile. Some of the off-flavors that are associated with soybeans disappear. And finally, some beneficial metabolites are produced in high amounts.”

The author has been working with chefs at Blue Hill at Stone Barns in New York to create delectable morsels using Neurospora mold grown on grains, legumes, and oat milk pulp waste.

The study discovered that this fungus could successfully convert cellulose-rich soy milk waste into food in just 36 hours.

Moreover, the study demonstrates the versatility of N. intermedia, which can grow on 30 different types of agricultural waste without producing any toxins. These wastes include sugar cane bagasse, tomato pomace, almond hulls, and banana peels.

Dessert from food waste

The author collaborated with Chef Rasmus Munk to conduct an experiment.

They presented red oncom to a group of 60 people who had never eaten it before. The flavor was described positively by the participants as “earthy, nutty, and mushroomy.”

Hill-Maini also tried growing Neurospora on various substrates such as peanuts, cashews, and pine nuts, which were all favorably welcomed.

Interestingly, Munk used Neurospora, along with the distinct flavors imparted by different substrates, to create a dessert for Alchemist’s menu.

The dessert consisted of a bed of jellied plum wine topped with unsweetened rice custard that had been inoculated with Neurospora, fermented for 60 hours, and then served cold with a lime syrup made from roasted lime peel.

“We experienced that the process changed the aromas and flavors in quite a dramatic way — adding sweet, fruity aromas. I found it mind-blowing to suddenly discover flavors like banana and pickled fruit without adding anything besides the fungi itself,” Munk said in the press release.

Hill-Maini told IE about the major challenges in scaling up the production of fungal-fermented foods. “The challenge will be understanding the fermentation in such detail that we can make it predictable, and rationally design processes for specific outcomes. Then we can understand what variables to tune to achieve specific growth, nutrition, flavors, etc. At my new lab at Stanford, we’ll be delving into that exactly,” he concluded.

The study can be accessed in the journal Nature Microbiology.