What is the difference between the pork red seal and blue seal

There is no difference in essence between the pork red seal and the blue seal, mainly the difference in color.

Pork red seal and blue seal is mainly the difference in color, these two Zhang actually means that pork is more qualified, but may be due to regional differences, each place is required to use a different seal color. But as long as there is a seal, usually meet the food quality standards.