Efficiencies and biomass appropriation of food commodities on global and regional levels

In examining the global food supply and demand, the balance of research has favored analysis of the prospects for increased crop production, at the expense of examination of the potential for reducing the production requirements by increases in efficiency and productivity, or by shifts in diets. This has implied that there is a lack of coherent evaluations of efficiency and diet as options for keeping down the long-term production requirements for crops and other food phytomass. This paper presents estimates of current efficiency and phytomass appropriation of major food commodities, performed by modeling all principal flows of biomass in the food system. Estimated overall efficiencies varied from 0.35% for beef cattle meat, to 31% for starchy root tubers (global averages, gross energy basis). The results indicate that there is a most substantial potential for efficiency improvements within the animal food sector, particularly for ruminant systems in non-industrialized regions. It is also concluded that a considerable reduction of the phytomass production might be achieved by shifts in diet, even if assuming no changes with respect to the total share of meat in the diet. (C) 2003 Elsevier Science Ltd. All rights reserved.