Java JPA where to use byte[] or Blob

Question

I'm trying to store images as binaries into a Postgres database with Java JPA.
I tried to use @Entity class with Blob field, which works well, but many people use just byte[] arrays. see #1, #2, etc.

What are the advantages and disadvantages of both?
When one should be preferred over another?

@Entity
public class ImageEntity {
    @Id
    private UUID id;
    @Lob
    @Fetch(FetchMode.JOIN)
    private Blob data;
}

// create Blob:         
byte[] myBytes = ...
Blob blob = new SerialBlob(myBytes);