According to the query on Gourmet World, the meat quality of pigs using red yeast rice changes as follows:

1. Red yeast rice can be used as a coloring agent to improve the stability of the meat color. This means that when you cook pork, the meat retains its bright red color and looks more attractive.

2. Red yeast rice can increase the tenderness of the meat. During the cooking process, Monascus protein phenol makes the meat more tender and tastes better.

3. Red yeast rice has a certain preservative effect and can extend the shelf life of pork. This is an important advantage for the meat industry.