It suppresses foaming that occurs when a naturally occurring water-soluble pigment such as spirulina blue pigment, anthocyanin pigment, gardenia pigment, or Monascus pigment is added to or dissolved in an aqueous solvent such as water. The solid composition containing a naturally occurring water-soluble dye is compressed.天然由来の水溶性色素、例えば、スピルリナ青色素、アントシアニン系色素、クチナシ色素、又はベニコウジ色素等を、水などの水性溶媒に添加、及び溶解した場合に生じる泡立ちを抑制する。天然由来の水溶性色素を含有する固体状組成物を圧縮処理する。