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Published on: August 6, 2018
What is on plates for school meals: focusing on animal- vs. plant-based protein foods
1Department of Food Science and Nutrition, Soonchunhyang University, Asan 31538, Korea.
Background/Objectives:
This study aimed to analyze the potential of school meals in South Korea as a sustainable tool to reduce carbon emissions by focusing on animal- vs. plant-based protein foods.
Materials/Methods:
By using a stratified proportional allocation method, 536 out of the 11,082 schools nationwide were selected including 21 kindergartens, 287 elementary-, 120 middle- and 108 high schools. A total of 2,680 meals served for 5 consecutive days (June 21-25, 2021) were collected. We analyzed the average serving amounts of protein foods (animal- vs. plant-based) per meal and then, calculated the estimated average amounts of carbon emission equivalents per meal by applying the conversion coefficients. The t-test and analysis of variance were used for statistical analyses (α = 0.05).
Results:
The average serving amount of animal-based protein foods per meal was 12.5 g, which was approximately 3 times higher than that of plant-based ones (3.8 g) (P < 0.001); the Meat-group had the highest average amount of 17.0 g, followed by Egg-group (9.6 g), Fish-group (7.6 g), and Beans-and-Nuts-group (3.8 g) (P < 0.05). Specifically, pork (25.1 g) was ranked first, followed by poultry (19.6 g), processed meat products (18.0 g). The estimated average amount of carbon emission equivalents of animal-based protein foods per meal was 80.1 g CO2e, which was approximately 31 times higher than that of plant-based ones (2.6 g CO2e) (P < 0.001); the Meat-group had the highest average amount of 120.3 g CO2e, followed by Fish-group (44.5 g CO2e), Egg-group (25.9 g CO2e), and Beans-and-Nuts-group (2.6 g CO2e) (P < 0.05). Specifically, processed meat products (270.8 g CO2e) were ranked first, followed by pork (91.7 g CO2e), and processed fish products (86.6 g CO2e).
Conclusions:
The results implied that school meals with plant-based alternatives could be a sustainable tool to improve carbon footprint.
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