Читать книгу Foods and Their Adulteration - Harvey Washington Wiley - Страница 124

—There are various forms of tanks used for producing steam rendered lard. In the open kettle there is a jacketed arrangement by means of which steam, at the proper temperature, is made to act upon the contents of the inner kettle. In the closed kettle the steam may be applied in the form of a jacketed arrangement or introduced directly into the kettle. The residues which remain after the steaming is completed and after the lard has been drawn off are withdrawn from the conical lower portion of the kettle which can be opened for the removal of these residues. A typical kettle for rendering lard is shown in Fig. 10. The fragments of meat to be received are placed in the opening M which is then properly closed when the tank is full. Steam is admitted and the condensation which is produced at first by the cold contents of the tank is drawn off through a water pipe. After the tank is thoroughly heated and the fat begins to separate the lard will rise above the water and the solid fragments and at the end of the process will fill the upper part of the tank. By means of the cocks at D it can be determined to what depth the tank is filled with lard and the lard can be drawn off through these cocks until water begins to flow. The bottom of the tank at G is then opened and the residues withdrawn, dried and ground for tankage.