For example, like the sweet potatoes with the softening treatment by heating with superheated steam, even when applied to water less and adhesion highly straining object is to allow without hindrance the recovery of filtrate. The periphery of the strainer container (3) with and surrounding at a distance the appropriate interval, the cover having a vertical and cross-section a circular inner peripheral surface which is rotatably supported around its central axis (26), the covering Meet of the predetermined positions along the inner peripheral surface, with the rotation of the covering, a scraping member for scraping off the filtrate adhering to the inner peripheral surface (22), said strainer container and the cover encompasses a rotation drive mechanism for rotating the body, whereby, when said strainer container is rotated, after being released from the filtration through hole (3d), filtrate adhering to the inner peripheral surface of said covering It is configured to scrape off the predetermined position on the circumference along the inner peripheral surface.例えば、過熱蒸気による加熱により軟化処理されたサツマイモのように、水分が少なくかつ付着性の高い裏漉し対象物に適用した場合であっても、濾過物の回収を支障なく行えるようにする。 ストレーナ容器(3)の周囲を適当な間隔を隔てて取り囲むと共に、その中心軸の周りに回転自在に支持された縦型かつ断面円形の内周面を有する覆い体(26)と、前記覆い体の前記内周面に沿った所定位置にあって、前記覆い体の回転に伴い、前記内周面に付着する濾過物を掻き落とすための掻き取り部材(22)と、前記ストレーナ容器及び前記覆い体を回転させるための回転駆動機構とを包含し、それにより、前記ストレーナ容器が回転する際、濾過用透孔(3d)から放出されたのち、前記覆い体の内周面に付着する濾過物を前記内周面に沿った円周上の前記所定位置に掻き落とすように構成する。
