Question

Yogurt is produced with the help of

• A. Lactobacillus bulgaricus
• B. Lactobacillus thermophilus
• C. Streptococcus thermophilus
• D. Both A and C

Answer 1

The correct option is D Both A and C

Yogurt is produced through the fermentation of milk by lactic acid bacteria, usually lactobacillus bulgarius and Streptococcus thermophilus. The milk is firstly heat treated, homogenised and is then cooled to allow the addition of bacteria or starter culture. This yogurt-milk mixture is then left overnight to ferment. The conversion of lactose in milk to lactic acid by the action of these bacteria drops the pH of the solution, causing the milk solids to become trapped in a gel matrix. This gel matrix of milk solids and proteins is called yogurt.