The digester, invented by Denis Papin in the 1680s, was a rudimentary pressure cooker used to soften hard bodies by boiling them at high pressure. In this paper, I propose a reassessment of Papin's work on the digester, arguing that his research was located at the intersection of the chemical laboratory and cooking practice. I then examine cases from the eighteenth-century European circulation of the instrument in Sweden, Italy and the Netherlands in order to showcase the different practices in which (...) the digester was embedded, including chemical research, philanthropic projects to feed the destitute, and proposals for the improvement of home cooking. The digester's history represents a key episode for demonstrating the intertwined nature of natural-philosophical research and the practice of economy or ‘thrift’. All users of the digester engaged in a rationalization of its functions through quantification, not only to fulfil a concern for precision but also to display the device's potential to reform practical daily life. The digester could save time and fuel, reduce material waste, make cooking easier and foster collective meal preparation for the needy. (shrink)