Greenhouse Gas Emissions Generated by Tofu Production: A Case Study

ABSTRACT

The objective of this study was to evaluate the greenhouse gas emissions (GHGEs) generated by the production of tofu. A partial life cycle assessment (LCA) was performed using SimaPro 8 software with a functional unit of 1 kg of packaged tofu and a farm to factory gate boundary. Original production data for the period of 1 year were obtained from a tofu manufacturer based in the United States and used with soybean production data from SimaPro 8 Ecoinvent 3.1 and U.S. Life Cycle Inventory databases to calculate the associated GHGEs as carbon dioxide equivalents (CO₂e). The LCA calculations included resource inputs required to produce and package tofu: soybeans, water, electricity, natural gas, transportation, and packaging materials. The LCA boundary was from the cradle (i.e., soybean farm) to the factory exit gate (i.e., postpackaging). Uncertainty analyses were performed using Monte Carlo simulations. Total CO₂e from packaged tofu were 982 g/kg, 9820 g/kg of protein, 1150 g/1000 calories, and 336 g/retail packet of 396 g. For 1 kg of packaged tofu, 16% of CO₂e resulted from soybean production, 52% from tofu manufacturing, 23% from packaging, and 9% from transportation. Tofu, a protein-rich plant food, generates relatively low GHGEs.

KEYWORDS:

• Tofu production
• life cycle analysis
• greenhouse gas emissions

Acknowledgements

We are grateful to the tofu factory for allowing us to access their site, interview personnel, and collect detailed tofu production data.

Funding

This research was funded by the McLean Fund for Nutrition Research.

Additional information

Funding

This research was funded by the McLean Fund for Nutrition Research.

Notes on contributors

Alfredo Mejia

A.M. conducted and finalized the data analysis. J.S. obtained funding, conceptualized and designed the research, collected the data, and edited the article. H.H. drafted and edited the article and finalized the data. K.J.S. collected the data and edited the article. K.S. collected the data. S.S. conceptualized and designed the research.