Who is to blame for food poisoning outbreaks in Singapore?

Cases of people falling seriously ill after eating contaminated food have been in the spotlight. Why does severe food poisoning happen and are caterers the only one to clean up their act?
Steven Chia and Crispina Robert speak to Dr Richard Khaw, deputy director of the School of Applied Sciences at Nanyang Polytechnic and Chris Loh, creative director of Purple Sage and Rasel Catering.
Here’s an excerpt from the conversation:
Steven Chia: 
You’re a larger caterer, you can automate some of the systems. Some of the smaller caterers may not be doing that; they may manually be doing everything.  
Chris Loh:
So that is a major problem when you do not have automation in the system.  
Crispina Robert: 
So, automation helps, but you still need people, right? Especially when you’re catering to big groups. Do all of them have to go for this food (safety) course, too? 
Steven: 
They’re supposed to, right? I went for it too. Because I did a (Talking Point) show and I worked at the cai fan (mixed vegetable rice) stall, and just to work for that one day, I had to go for the very basic food safety course … They teach you how to store raw food, how to wash your hands, and how you got to separate the different types of raw and cooked food.  
Crispina:
But is it possible that someone is hired to do the back-end stuff, because you can’t see, right, who didn’t go through the food safety course? 
Richard Khaw: 
Legally, no. 
Steven: 
But does it happen?  
Chris:
… Yes, other caterers may have that practice. 
Steven: 
So you are saying it does happen, like during festive seasons, when you need extra hands, you just hire whoever is available? 
Richard: