A: What are your thoughts on the recent food safety scandal surrounding milk tea shops?

B: As in many industries, this could well be a case of a few bad apples tarnishing the reputation of the rest.

Note: Both phrases “rotten apple” and “bad apple” basically mean the same thing — an individual or institution whose negative behavior or attitude impacts those around them. But “bad apple” is more commonly used in everyday language. This idiomatic expression dates back to the days when the preservation of food was not as sophisticated as it is today. People observed that one rotten apple in a barrel or bunch could cause the others to spoil, thus giving rise to this metaphor.