The staple food of the Neolithic period was grain porridge with fruit and oil-rich seeds. The grain first had to be freshly ground – or, to be more precise, crushed on a millstone – before being mixed with water. Add berries, nuts, vegetables, herbs and, in good times, fish or meat too – and a nutritious meal was ready. Good bread required very finely ground grain. To produce one kilo of flour, the Stone Age grain mill had to be in operation for about an hour – entirely by hand, of course.