What You Need to Know
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.
Creates a thick, spoonable texture with balanced acidity, distinct from mesophilic fermented dairy products.
Key Parameters
Temperature
42°C
40°C - 45°C
Time
6-8 hours
4 hours - 12 hours
Equipment
Thermostatic incubatorSterile cheeseclothpH meterWater bath with circulator
Steps
- 1.
Greek strained yogurt (Eastern Mediterranean): Creates protein matrix capable of whey retention
- 2.
Dahi (Indian subcontinent): Enables overnight fermentation in warm climates
The Science
Primary Reaction
Lactose → Lactic acid + Acetaldehyde