Abstract: A method and system for food preparation and processing that determines the bulk density of food particulate matter input into particulate packaging machinery and performs bulk density feedback of packaged food particulate matter. The feedback mechanism inputs bulk density values into a controller that are referred against acceptable values. Where the input values of bulk density are outside the acceptable range the controller automatically alters the food preparation and packaging process to obtain acceptable bulk density values. The method system are applicable to any food manufacturing process, although they are particularly well suited to the manufacture of food in flake, chip, puffed or extruded form.