Abstract
Background: Global warming and climate change, caused by greenhouse gas emissions (GHGE), is a significant problem facing today’s society. The New Zealand government has set targets to reduce national GHGE. Agriculture is responsible for 47% of New Zealand’s emissions. International research estimates that 15-30% of global emissions can be attributed to food production and many of the foods with the highest emissions are protein rich foods in the meat and meat alternatives food group. A shift in foods eaten from this group could lead to a reduction in both personal and national emissions.
Aim: The aim of the study was to estimate the GHGE of a variety of foods in the meat and meat alternatives food group produced in New Zealand using Life Cycle Assessment.
Methods: Seven farms participated in the study. The farms produced eggs (both conventionally farmed and free range), chicken, farmed salmon, lamb, beef and pork. The farmers completed a questionnaire via email. Information was collected on the what the farm produced and its inputs and outputs, e.g. fuel use, electricity use, feed requirements, irrigation, fertiliser and pesticide use, animal housing, manure management, machinery usage and soil type. Processing, land use change, capital goods such as farm buildings and transport within New Zealand were excluded. A theoretical model was built to estimate emissions from tofu manufactured from imported soybeans. Data was analysed using SimaPro 7 software.
Results: The carbon emissions from each food per kg of raw food were as follows; lamb 11.2 CO2e/kg, beef 10.4 CO2e/kg, salmon 8.9 CO2e/kg, pork 6.2 CO2e/kg, chicken 2.4 CO2e/kg, eggs (free range) 2.1 CO2e/kg, eggs (intensive) 1.9 CO2e/kg, and tofu 1.2 CO2e/kg. The carbon emissions from each food per kg of protein were as follows; salmon 49.3 CO2e/kg, lamb 49.1 CO2e/kg, beef 34.1 CO2e/kg, pork 26.9 CO2e/kg, eggs (free range) 15.8 CO2e/kg, tofu 15.1 CO2e/kg, eggs (intensive) 14.8 CO2e/kg and chicken 9.8 CO2e/kg. The carbon emissions per portion followed a similar pattern.
Conclusions: Beef, lamb and farmed fish had higher estimated GHGE compared to the other foods. Pork had moderate emissions and the foods with low emissions were eggs, chicken and tofu. In order for New Zealanders to reduce their personal GHGE they could consume less red meat, less farmed fish and more eggs, chicken and plant-based meat alternatives