What is the flour sifter for? What is its function?

A "flour sifter" is a tool used to sift flour. The so-called sifting is to put the flour in the sieve and shake it. The flour that flows down through the fine "sieve holes" is the "sifted" flour. It is equivalent to filtering the flour and mixing it thoroughly.

According to the master chef, sifted flour is very helpful for fermentation and the appearance and taste of the finished product.