Sponge method - Kaimenho

… The methods for extracting essential oils vary depending on the plant and material, but can be broadly classified into pressing, extraction, and steam distillation. Pressing involves crushing the peels of citrus fruits to extract the essential oil. There are also other methods, such as the Echiniel method, which uses a cup-shaped tool with protrusions, the sponge method, in which the essential oil is extracted by hand pressing and then absorbed into a sponge and then squeezed out, and mechanical extraction, in which the entire process is mechanized. Extraction is used for materials that are unstable to heat, such as flower essential oils. …

*Some of the terminology used in reference to the "sponge method" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…　精油の採取法は植物，素材種により異なるが，圧搾法，抽出法，水蒸気蒸留法に大別される。圧搾法はかんきつ類の果皮を押しつぶして精油を採取する方法で，突起のあるわん状の器具を用いるエキニエル法，手で圧搾して浸出する精油をいったん海綿に吸収させたあと搾りとる海綿法，全作業を機械化した機械搾油がある。抽出法は花精油などのように熱に不安定なものに適用される方法である。…

※「海綿法」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報