Description
Controlled bacterial fermentation of milk at elevated temperatures favoring thermophilic cultures.
Technical
Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus metabolize lactose into lactic acid (C3H6O3) at optimal thermal conditions, lowering pH to 4.0-4.5 while producing exopolysaccharides.
Culinary Significance
Creates a thick, spoonable texture with balanced acidity, distinct from mesophilic fermented dairy products.
Science
Primary Reaction
Lactose → Lactic acid + Acetaldehyde
Parameters
Temperature
42°C optimal
40°C to 45°C range
Time
6-8 hours
4 hours – 12 hours
Equipment
Thermostatic incubatorSterile cheeseclothpH meterWater bath with circulator