| 摘要 |
PURPOSE:To obtain a feed for culturing fishes capable of adding a large amount of fats and oils to a stable feed by using a specific twin-screw extruder in which a structure of the screw tips and die part is changed and granulating a prescribed assorted feed. CONSTITUTION:A powdery feed of the type in which a large amount of fats and oils is added without using a live bait is granulated by using a water-soluble binder and/or a thermoplastic emulsifying agent. In the process, the following twin-screw extruder is used. That is the aforementioned twin-screw extruder is prepared by removing conical parts at the screw tips and providing scraping parts of the same diameter as that of screws 1. The above-mentioned scraping parts are designed to house scraping blade installing parts 2 and scraping blades 4. Thereby, since a gap is formed around the scraping blades just before passing a kneaded material through a die hole 6, the material fed until the pressure required for its passage through the die is kept constant is stocked in the gap. |
