Soy Sauce Fermentation with Cordyceps militaris: Process Optimization and Functional Profiling

Area of Science:

• Food Science and Technology
• Mycology
• Biotechnology

Background:

• Soy sauce is a popular fermented condiment with a long history.
• Medicinal mushrooms like Cordyceps militaris (C. militaris) are known for their bioactive compounds.
• Enhancing the nutritional and functional properties of soy sauce is of significant interest.

Purpose of the Study:

• To develop and optimize a functional soy sauce fermented with Cordyceps militaris (C. militaris).
• To improve the nutritional and functional properties of soy sauce using C. militaris as the sole starter culture.
• To investigate the impact of C. militaris fermentation on sensory attributes and bioactive compound content.

Main Methods:

• Response surface methodology was used to optimize fermentation parameters.
• Koji fermentation conditions (temperature, aeration, inoculum concentration) were optimized for protease activity and cordycepin production.
• Main fermentation conditions (temperature, brine concentration, water-to-material ratio) were optimized for amino acid nitrogen and bioactive compounds.

Main Results:

• Optimal conditions yielded soy sauce with 1.14 g/100 mL amino acid nitrogen and 16.88 mg/100 mL cordycepin.
• The C. militaris-fermented soy sauce showed a darker color and enhanced umami taste compared to traditional soy sauce.
• A distinct volatile profile was observed, including linoleic acid, methyl palmitate, and niacinamide.

Conclusions:

• Cordyceps militaris (C. militaris) can be successfully used as a starter culture for soy sauce fermentation.
• This novel fermentation process improves the nutritional value, bioactive compound content, and sensory quality of soy sauce.
• The resulting functional soy sauce has potential as a valuable health-promoting condiment.