Comparing environmental impacts of regional and national-scale food supply chains: A case study of processed tomatoes

Our results indicate that California-produced conventional and organic tomato paste and canned diced tomatoes are almost equivalent in energy use and GHG emissions to regionally produced and consumed products, but use of developed water resources is significantly higher for California-grown products. California tomato production benefits from higher per hectare yields and soil amendments with lower carbon dioxide emissions. These efficiencies substantially offset the added energy use and GHG emissions associated with long-distance shipment of products to the Great Lakes region, as long as shipments are made by rail rather than by truck. Paste, the more processed and concentrated product evaluated, amplifies any environmental advantages or disadvantages accrued in the field production stage, due to its raw tomato to finished product ratio of 6:1, suggesting that comparative regional advantage can play a role in lowering life cycle environmental impacts of highly condensed foods shipped long distances.