What You Need to Know
During fermentation, lactic acid bacteria (e.g., Lactobacillus kefiranofaciens, Lactobacillus kefiri) reduce lactose to lactic acid, while yeasts such as Saccharomyces and Kluyveromyces produce ethanol and CO₂. Acetic acid bacteria contribute to flavor by oxidizing ethanol to acetic acid. The combined activity lowers pH to 4.3–4.6, causing casein or plant protein aggregation and the synthesis of kefiran, a viscous polysaccharide that enhances texture and provides a probiotic matrix.
The Science
Primary Reaction
Fermentation of lactose or plant sugars by lactic acid bacteria, acetic acid bacteria, and yeasts producing lactic acid, ethanol, CO₂, and kefiran polysaccharide