Question

Which of the following is the correct sequence for the yoghurt production?
I. Streptococcus thermophilus and Lactobacillus brevis are added in 1:1 ratio.
II. Milk is boiled and left to cool to warm temperature.
III. Milk powder is mixed with the milk for fermentation.
IV. Lactic acid is produced which acts on the milk protein.

• A. III $\Rightarrow$ II $\Rightarrow$ IV $\Rightarrow$ I
• B. III $\Rightarrow$ II $\Rightarrow$ I $\Rightarrow$ IV
• C. III $\Rightarrow$ I $\Rightarrow$ IV $\Rightarrow$ II
• D. IV $\Rightarrow$ II $\Rightarrow$ III $\Rightarrow$ I

Answer 1

The correct option is B III $\Rightarrow$ II $\Rightarrow$ I $\Rightarrow$ IV

Yoghurt is one of the milk products and it's production involves some of the microorganisms.
Steps of yoghurt production are:
Step I: In order to maintain the protein content of the product, milk powder is mixed with milk.
Step II: Milk is boiled and allowed to cool until the temperature is warm.
Step III: Bacterial strains of Streptococcus thermophilus and Lactobacillus delbrueckii is added to the warm milk in 1:1 ratio.
Step IV: Streptococcus thermophilus results in the production of lactic acid, which acts on milk protein to give yoghurt.