The production of food that is not consumed unnecessarily consumes natural resources, generates greenhouse gas emissions and creates waste. In order to assess the environmental impact of a food product, we need to consider its entire life cycle and track every step of the food supply chain.
We can consider three indicators: the carbon footprint, the environmental footprint, and the water footprint. Ecological Footprint is an indicator used to assess the environmental impact of the consumption of a given population: it quantifies the total area of terrestrial and aquatic ecosystems necessary to provide all the resources used in a sustainable manner and to absorb all sustainable emissions produced. The ecological footprint is a composite indicator that measures the different ways of using environmental resources through a single unit of measurement that includes specific conversion and equivalence factors: the global hectare.
The approach to calculating the ecological footprint is similar to that of an LCA study. Convert the environmental aspects of the production process, in particular CO2 emissions and land use, into an “equivalent” area (global hectare).
As with the carbon footprint, the final value determined with these calculations does not refer to the area actually occupied but is a theoretical representation that takes into account the exposure to various factors. The water footprint or virtual water content is a specific indicator of freshwater consumption and is intended to reflect both the water resources actually consumed and the way in which water is used.
In food production, the water consumed in the industrial production stage as well as evaporation from irrigated agriculture is taken into account. per kg of waste and per total.
The data shows how the amount of fruit and vegetables discarded at the point of sale consumes more than 73 million m3 of water, the use of environmental resources is equivalent to about 400 million m2, and the emission into the atmosphere is more than 8 million kg of carbon dioxide. Data of the impact of meat, tells us that throwing away 22,000 tons of meat products means wasting about 127 million m3 of water and emitting the equivalent of 9. 8 million tons of carbon dioxide into the atmosphere and consuming the environmental resources by 8,360 hectares of land.
The production of food waste has a significant impact on the environment. The uneaten parts of food in landfills contribute to global warming. Food waste breaks down and produces harmful methane, which is released into the atmosphere. Methane is one of the toxic greenhouse gases and is 21 times stronger than carbon dioxide. Globally, landfill gas accounts for 7% of total greenhouse gas emissions.
If this food were properly composted, less harmful carbon dioxide could be released into the air instead of methane. Another factor that affects the environment, in addition to food landfills, is the long-distance distribution of food or its subsequent disposal. These processes require a large amount of fuel, which in the long term is significantly affected by exhaust emissions.
The FAO has implemented a project called Food Wastage Footprint (FWF) which shows that reducing food waste is a logical priority for creating more sustainable ways of producing and consuming food and providing a global view of the environmental footprint along the food chain.
The project used the Life Cycle Assessment (LCA) model to assess the magnitude of the environmental impact and to identify food products for the regions and stages of the food chain where appropriate mitigation actions should be taken.
In the second phase of the FWF project , environmental impacts were measured at social costs. It has developed a methodology to assess the direct financial costs, depreciation of ecosystem goods and services, and loss of welfare associated with degradation of natural resources. The total cost of food waste is approximately US$2.6 billion per year including environmental costs of US$700 billion and social costs of US$900 billion.
The global food supply is a real problem. Increased food production will be reflected in higher GHG emissions from deforestation as land is attacked for food production, as well as increased waste production.