1. Types of fermented or probiotic foods:
- Yogurt: A popular fermented food made from milk and containing live cultures of bacteria, mainly Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus.
- Sauerkraut: Fermented cabbage made by lactic acid bacteria, mainly Leuconostoc spp.
- Kimchi: A traditional Korean side dish made from fermented vegetables, such as cabbage, radishes, and cucumbers, using lactic acid bacteria like Leuconostoc mesenteroides and Lactobacillus species.
- Kefir: A fermented milk beverage made by adding kefir grains, which consist of a symbiotic culture of yeast and lactic acid bacteria.
- Miso: A traditional Japanese seasoning made from fermented soybeans or other grains, often using Aspergillus oryzae as the main fermenting microorganism.
- Kombucha: A fermented tea beverage made by adding a symbiotic culture of bacteria and yeast known as a SCOBY (symbiotic culture of bacteria and yeast).
2. Types of microorganisms involved in food fermentation:
- Lactic acid bacteria (LAB): The most common group of bacteria involved in food fermentation, including species such as Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus casei.
- Yeasts: Single-celled fungi that convert sugars into alcohol and carbon dioxide during fermentation. Examples include Saccharomyces cerevisiae used in bread-making, and Zygosaccharomyces and Kluyveromyces species used in beverage fermentation.
- Mold: Fungi that play a role in some types of fermentation, such as in the production of certain cheese varieties. Examples include Penicillium camemberti used in Camembert and Brie cheese production.
3. Species or subspecies/strains associated with fermented foods:
The exact species or subspecies/strains of microorganisms used in fermented foods can vary depending on the specific food and manufacturing process. For example:
- For yogurt, commonly used species include Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus.
- For sauerkraut, different species of Leuconostoc and Lactobacillus may be involved.
- In the production of miso, different strains of Aspergillus oryzae may be used.
- In kombucha, typical microorganisms include Acetobacter, Gluconobacter, and various yeasts.
4. Process flow diagram:
The process flow diagram for food fermentation can vary depending on the specific food and production method. However, here is a general overview of the steps involved:
- Raw material preparation: Select and prepare the ingredients.
- Pre-fermentation treatment: Heat treatment, chopping, or mixing to enable the growth of desired microorganisms.
- Inoculation: Add the starter culture or inoculum containing the desired microorganisms.
- Fermentation: Allow the mixture to undergo controlled fermentation, usually under specific temperature, pH, and time conditions to encourage the growth of desired microorganisms and the production of desired flavors.
- Post-fermentation treatment: Heat treatment, cooling, or aging to halt the fermentation process and promote flavor development.
- Packaging: Package the final fermented product for distribution and storage.
Note: The specific conditions, timings, and additional steps can differ based on the specific product being made.