Kombu Fermentation Breakthrough: Boosting Nutrition and Flavor with Probiotics
Kombu, a type of edible kelp widely consumed in East Asia, particularly in Japan, Korea, and China, is gaining attention for its potential as a superfood. However, its strong odor and the limited bioavailability of its nutrients have historically hindered wider adoption. Now, researchers at the National University of Singapore (NUS) have developed a novel fermentation process that addresses both challenges, unlocking kombu’s nutritional benefits and enhancing its flavor profile.
The Challenges with Kombu Consumption
While kombu is rich in essential nutrients, including iodine, calcium, iron, and vitamins A and C, many of these benefits are demanding for the human body to access. The nutrients are often locked within the kelp’s rigid cell walls [3]. Kombu’s characteristic fishy and grassy odor can be unappealing to some consumers.
NUS Researchers’ Innovative Approach
The NUS team, led by Associate Professor Liu Shao Quan, built upon existing methods of enzymatic treatment and lactic acid bacteria (LAB) fermentation. While these techniques improve nutrient bioavailability, they don’t eliminate the undesirable odors. The researchers discovered that co-fermenting enzyme-treated kombu with LAB and an aroma-producing yeast could overcome both hurdles.
Their research, published in the International Journal of Food Microbiology in December 2025 [4], demonstrates that this co-fermentation process not only releases trapped nutrients but also introduces pleasant fruity and floral aromas. Earlier work, published in October 2025, had already shown the effectiveness of LAB fermentation in releasing nutrients.
Benefits of LAB-Yeast Co-Fermentation
Analysis of the fermented kombu blend revealed several key benefits:
- Enhanced Probiotic Growth: The co-fermentation promotes the growth and survival of probiotics compared to LAB-only fermentation.
- Increased GABA Production: A specific co-fermentation mixture (using L. Plantarum and P. Kluyveri) yielded higher levels of γ-aminobutyric acid (GABA), a bioactive compound linked to calming effects, stress reduction, and mental health benefits.
- Reduced Off-Flavors: The process significantly reduces unpleasant odors.
- Fruity Aromas: The co-fermentation introduces compounds associated with the aromas of bananas and pears.
Future Applications and Commercial Potential
The researchers envision a range of fresh health products based on this fermented kombu blend, including:
- Fermented seaweed drinks
- Probiotic seaweed-based supplements
- Ingredients for plant-based foods
Currently, few commercial kombu products utilize LAB-yeast fermentation, highlighting the innovative nature of this research. The team is now focused on optimizing fermentation conditions – including sequence, time, and temperature – to improve process efficiency and product quality. Future research will also include sensory evaluation to understand consumer preferences for seaweed-based foods.
“Elevating the flavour profile of kombu makes it more enticing to a broader range of consumers,” said Ms Geng Chenhan, a PhD student and first author of the research paper.
What is Kombu?
Kombu is edible kelp, primarily from the Laminariaceae family, and is a staple in East Asian cuisine [1]. It is also known as dasima in Korean [2] and haidai in Chinese [1]. It’s a key ingredient in making dashi, a foundational broth in Japanese cooking, and adds umami, a savory taste, to dishes due to its high glutamic acid content [3].