Which statement about acidity and pathogen growth is true?

• A. Pathogens grow best in foods with low acidity; acidic ingredients can hinder growth.
• B. Pathogens grow best in highly acidic foods; adding lemon speeds growth.
• C. Acidity does not affect growth.
• D. Pathogens require alkaline foods to grow.

Answer: (A)

Acidity level of a food strongly influences whether pathogens can multiply. Most foodborne pathogens prefer near-neutral conditions, so as acidity increases (pH drops), their growth is slowed or halted. Therefore, foods with low acidity (less acidic, closer to neutral) provide a more favorable environment for many pathogens to grow, while adding acidic ingredients raises the acidity and hinders their multiplication. This is why acidic ingredients like lemon juice or vinegar are often used to preserve foods and reduce microbial growth. The idea that pathogens grow best in highly acidic foods is not correct, because high acidity generally suppresses microbial growth. And acidity does affect growth, so the statement about acidity being irrelevant misses a key factor in food safety.