| Component Category |
Specific Components |
How They Are Formed |
Nutritionist Explanation |
| Organic Acids |
Lactic acid, acetic acid |
Bacterial fermentation of lactose |
Organic acids lower pH, change flavour, and influence the final food matrix. They are a defining feature of fermented foods. |
| Bioactive Peptides |
Casein-derived peptides |
Enzymatic breakdown of milk proteins |
Fermentation enzymes partially break down proteins, producing peptides not present in fresh milk. |
| Free Amino Acids |
Leucine, valine, glutamic acid (varies) |
Protein hydrolysis during fermentation |
Increased availability of amino acids explains why fermented dairy is often described as “pre-digested.” |
| Exopolysaccharides (EPS) |
Kefiran |
Produced by specific kefir microorganisms |
EPS contribute to kefir’s texture and viscosity and are unique to kefir fermentation. |
| B-Group Vitamins |
B2 (riboflavin), B12, folate (levels vary) |
Microbial synthesis during fermentation |
Certain microorganisms can synthesise or increase availability of B vitamins during fermentation. |
| Carbon Dioxide (CO₂) |
Natural carbonation |
Yeast fermentation activity |
Explains the slight effervescence sometimes observed in kefir milk. |
| Ethanol (trace) |
Very low alcohol content |
Yeast metabolism of sugars |
Present in trace amounts (<1%), typical of mixed fermentation foods and not considered alcoholic. |
| Enzymes |
Lactase-like enzymes |
Produced by microorganisms |
Contributes to partial lactose breakdown and changes in digestibility. |
| Modified Milk Sugars |
Reduced lactose content |
Microbial metabolism |
Lactose is partially utilised during fermentation, altering the carbohydrate profile. |
| Altered Fat Structure |
Short-chain fatty acid availability |
Microbial lipase activity (minor) |
Small changes in fat structure can influence flavour and mouthfeel. |