Question

Extraction of energy from carbohydrate in the absence of oxygen giving alcohol by yeast and lactic acid by bacteria is used for

• A. Butter making
• B. Distilled cow urine
• C. Yogurt making
• D. Cow dung wood making

Hint:

Industrial Fermentations:
Lactic Acid Fermentation (LAB) $\rightarrow$ Yogurt, Cheese, Curd, Silage.
Alcoholic Fermentation (Yeast) $\rightarrow$ Beer, Wine, Ethanol, Bread.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Industrial dairy biotechnology harnesses homolactic fermentation of lactose into lactic acid by probiotic lactic acid bacteria.
Key Formula or Approach:
\[ \text{Lactose} \xrightarrow{\beta\text{-Galactosidase}} \text{Glucose} + \text{Galactose} \xrightarrow{\text{Glycolysis}} 2\text{ Pyruvate} \xrightarrow{\text{LDH}} 2\text{ Lactic Acid} \]

Step 2: Detailed Explanation:
In fermented dairy product manufacturing:
- Yogurt Making is an anaerobic industrial food fermentation process:
- Thermophilic lactic acid bacteria (Lactobacillus delbrueckii subsp. bulgaricus and {Streptococcus thermophilus) ferment milk sugar (lactose) anaerobically into lactic acid.
- The resulting drop in pH ($pH \approx 4.5$) causes isoelectric precipitation of casein micelles, producing the smooth, firm coagulum gel characteristic of yogurt.

Step 3: Final Answer:
Thus, this anaerobic process is used for Yogurt making, matching option (C).