The present invention provides methods and products made thereby, wherein a pre-expanded constituent, including an edible constituent, is thermally treated to melt it, preferably in a dynamic process environment, to produce products ranging from high to quite low densities and from very strong to soft to apparently dry textures. The wide range of textures enables the provision of food products such as low calorie, digestible and safe, long duration pet food chews. Non-food products suitable for use in manufacture may also be produced. Cooking is preferably carried in an extruder, preferably at low moisture or in the total absence of added water. The methods of dynamic cooking reduce cost in a number of ways including but not limited to decreased process steps, increased throughput, decreased capital expenses and decreased raw product cost. <;IMAGE>;