Scientists can tune the flavour of chocolates by tweaking microbes, PgII

Key Highlights:

• Scientists studied cocoa bean fermentation in Colombia across two growing seasons, monitoring temperature and pH levels in Santander, Huila, and Antioquia districts.
• The study revealed that microbial diversity decreases over time during fermentation, with different microbes dominating at different stages.
• Researchers found that bacteria in fermentation boxes retain a "memory," while fungi likely come from various environmental sources.
• By manipulating the microbial community in the lab, scientists were able to alter the flavor profiles of chocolate.

Detailed Insights:

• Cocoa bean fermentation, like yogurt and kimchi production, relies on microorganisms to transform carbohydrates without oxygen.
• The location of cocoa bean fermentation significantly impacts flavor profiles due to the spontaneous arrival of microbes from the environment.
• In Santander, bean temperatures rose after 24 hours, indicating microbial growth, while pH levels became highly acidic before rising again.
• Metagenome sequencing showed that bacterial and fungal diversity decreased over time as microbes broke down nutrients.
• Reproducing key microbial features in the lab allowed scientists to observe patterns similar to those seen on farms.
• Removing specific microbes altered the outcomes, indicating that the microbial composition depends on the starter community and fermentation time.
• The research suggests the possibility of producing chocolate with specific flavor profiles using tailored starter cultures, similar to the beer or cheese industries.

Scientific/Technical Concepts Involved:

• Fermentation: A metabolic process that converts carbohydrates to acids, gases, or alcohol in the absence of oxygen.
• Metagenome Sequencing: A technique used to study the genetic material recovered directly from environmental samples.
• pH Level: A measure of how acidic or basic a substance is, ranging from 0 to 14.