How come goblet cells appear blue in H&E staining in case of Barret esophagus?

How come goblet cells appear blue in H&E staining in case of Barret esophagus?

I remember we studied in histo that these cells appear empty on H&E staining because eof mucous. So someone please comment.

In Barrett’s esophagus goblet cells contain mucin and to stain mucin a special stain called Alcian blue is used.

Thank you.

It’s alcian blue staining not on h/e