Foodborne IllnessQuestion 4 of 240
A supervisor wants to slow bacterial growth in a house-made salsa by adjusting acidity. Bacteria grow best in foods with a pH in which range?
a.Below 4.6 (highly acidic)
b.Exactly 0 (pure acid)
c.Above 9.0 (alkaline)
d.Between 4.6 and 7.5 (slightly acidic to neutral)
Explanation
Most disease-causing bacteria grow best in foods with a pH between 4.6 and 7.5. Lowering the pH below 4.6 with acid, like the vinegar or citrus in salsa, inhibits their growth, which is why acidified foods are safer. Very alkaline conditions are also unfavorable, but kitchens control risk mainly by acidifying and refrigerating.
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