Question

What should be the temperature for pasteurization of fruit juices?

• A. 30-40\(^{\circ}\)C for 20-30 minutes
• B. 50-60\(^{\circ}\)C for 20-30 minutes
• C. 70-80\(^{\circ}\)C for 20-30 minutes
• D. 85-90\(^{\circ}\)C for 20-30 minutes

Hint:

Juice is bottle pasteurized in hot water, about 85-90 degrees C.

Answer 1

The Correct Option is D

Step 1: State the aim:
We need a heat dose that kills yeasts and moulds in an acidic juice without cooking the flavour away.

Step 2: Use pH knowledge:
Fruit juice is acidic, so bacterial spores cannot grow. Heating below boiling is enough.

Step 3: Pick the range:
Texts on fruit preservation give 85 to 90 degrees C for 20 to 30 minutes for bottled juice.

Step 4: Compare options:
Options (1) and (2) are too cool to kill microbes. Option (3) is lower than the textbook value. Option (4) matches.

Final Answer:
Option (4) matches the textbook range. \[ \boxed{\text{Option (4)}} \]