Koji (a culture of Aspergillus oryzae) is traditionally found in sake, miso and soy sauce; more recently, it is being repurposed to engineer plant-based meats. In one approach, koji grows filamentous networks that mimic muscle fibres, then is infused with plant fats and seasoning to create cuts of “meat”. Because its enzymes break down proteins and starches, koji also boosts umami in other plant-based ingredients, making them taste richer without heavy processing.
