Temperature impact on microbial and metabolic profiles in kimchi fermentation

Area of Science:

• Food Science
• Microbiology
• Fermentation Technology

Background:

• Kimchi, a traditional Korean fermented food, relies on microbial activity for its characteristic flavor and preservation.
• Effective temperature management is crucial for controlling kimchi fermentation and ensuring desired sensory qualities.

Purpose of the Study:

• To investigate the impact of fermentation temperature on the bacterial community composition and metabolite profiles of kimchi.
• To elucidate the role of temperature in modulating kimchi's microbial succession and metabolic pathways.

Main Methods:

• Bacterial community analysis using pyrosequencing.
• Metabolite profiling via liquid chromatography-mass spectrometry (LC-MS).
• Comparative analysis of kimchi fermented at 4°C, 10°C, and 15°C.

Main Results:

• Elevated temperatures (10-15°C) increased bacterial diversity and richness, favoring species like *Lactiplantibacillus plantarum* and *Latilactobacillus sakei* while decreasing *Lactococcus lactis*.
• Significant increases in metabolite production, including lactic and succinic acids, were observed at higher temperatures due to enhanced glycolysis and TCA cycle activity.
• Approximately 5000 metabolites were identified, with notable increases in specific metabolite counts at 10°C and 15°C.

Conclusions:

• Fermentation temperature critically influences kimchi's bacterial succession and metabolic output.
• Optimized temperature control (10-15°C) can enhance kimchi fermentation, leading to increased acidity and desirable flavor profiles.
• Understanding these temperature-dependent microbial and metabolic shifts is key to controlling kimchi's sensory properties.