Question

Coliform bacteria in canned cheese causes

• A. Late blowing
• B. Browning
• C. Early blowing
• D. Corrosion

Hint:

Coliforms (lactose fermenters) cause Early Blowing within 1--2 days; Clostridium tyrobutyricum causes Late Blowing weeks later.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Gas production defects in cheese during manufacturing and ripening are categorized into early blowing and late blowing.

Step 2: Detailed Explanation:
Early blowing defect occurs within the first 1 to 2 days of cheese manufacture or initial storage.
It is caused by coliform bacteria (such as Escherichia coli and Enterobacter aerogenes) that rapidly ferment lactose, producing carbon dioxide ($\text{CO}_2$) and hydrogen ($\text{H}_2$) gas along with unpleasant volatile off-flavors.
Late blowing occurs weeks later during ripening due to anaerobic spore-forming Clostridium tyrobutyricum producing butyric acid and $\text{H}_2/\text{CO}_2$.

Step 3: Final Answer:
Hence, coliform bacteria cause early blowing in cheese.