1. When ordering food at McDonald's and KFC, the service staff will put a piece of paper similar to advertising paper on the tray and squeeze it directly on the paper when eating French fries dipped in tomato sauce.

2. Some people crowded into other food boxes.

3. Some people don't trust the hygiene of paper, so they squeeze ketchup on napkins.

4. Ketchup is a concentrated sauce product of fresh tomatoes. It is a bright red sauce with the unique flavor of tomato, and it is a very distinctive condiment, which is generally not eaten directly. Tomato paste is made from ripe red tomatoes by crushing, pulping, removing rough substances such as peel and seeds, concentrating, canning and sterilizing.

Ketchup is usually used as cooking seasoning for fish, meat and other foods. It is a good seasoning for adding color, acid, freshness and fragrance. The application of tomato sauce is an important seasoning content to form the flavor characteristics of Cantonese cuisine in Hong Kong.