P-27 - From Tradition to Innovation: Koji Enzymes in Next-Gen Fermentation

Koji has played a significant role in Asian food and beverage production for centuries, with three main types utilized in fermentation: yellow Koji (Aspergillus oryzae) for sake, white Koji (Aspergillus luchuensis mut. kawachii) for shochu, and black Koji (Aspergillus luchuensis var. awamori) for shochu brewing. These molds produce a variety of enzymes, including cellulase, protease, amylase, and lipase, which break down complex grain structures, releasing essential nutrients for microbial activity. Such enzymatic hydrolysis is critical for various fermentation processes, including alcoholic fermentation, acidic production, and mixed sour fermentations such as those seen in kombucha-like beverages. Additionally, Koji is typically cultivated on rice but can be grown on alternative grains, allowing the development of naturally gluten-free products when non-gluten starch sources are fully substituted. This characteristic is particularly beneficial for consumers with celiac disease.

This study investigated the application of yellow and white Koji enzymes as potential alternatives to barley malt and purified exogenous enzymes in non-alcoholic beer (NAB) production. Results demonstrated that yellow Koji exhibited superior enzymatic activity, particularly α-amylase, leading to a higher original gravity and increased sugar composition in wort. In contrast, white Koji showed high potential for protein degradation and amino acid release, which could be advantageous for fermentation and overall flavor development.

Beyond NAB production, integrating unmalted rice with Koji offers significant potential to streamline production time and enhance flavor complexity. These findings also suggest broader applications in the development of innovative food and beverage products. The enzymatic capabilities of Koji could help address pressing challenges such as celiac disease-friendly formulations, increasing consumer demand for healthier alternatives, and localizing production in regions with limited access to traditional raw materials. Additionally, Koji-based fermentation methods could contribute to sustainability efforts by reducing reliance on energy-intensive malt production and mitigating supply chain disruptions caused by global crises.

Overall, this research highlights Koji enzymes as a viable and innovative tool in modern food and beverage processing. With further optimization, Koji-based approaches could enhance product quality, improve manufacturing efficiency, and expand the range of gluten-free and health-conscious fermentation products available to consumers.