Life cycle environmental impacts of convenience food: Comparison of ready and home-made meals

This paper compares the life cycle environmental impacts of ready-made meals manufactured industrially with meals prepared at home from scratch. A typical roast dinner consisting of chicken meat, and tomato sauce is considered. The results suggest that the impacts of the home-made meal lower than for the equivalent ready-made meal. For example, the global warming and human toxicity are up to 35% lower and eutrophication, photochemical smog and ozone layer depletion are up 3 times lower. The main reasons for this are the avoidance of meal manufacturing, reduced refrigeration and a lower amount of waste in the life cycle of the home-made meal. For the ready-made meal, lowest impacts are found for the frozen meal prepared from fresh ingredients and heated at home in microwave. The worst option for most impacts is the frozen ready-made meal with frozen ingredients is heated in an electric oven. For the same cooking method, chilled ready-made meals have higher than the frozen. The type of refrigerant used in the supply chain influences the impacts, global warming and ozone layer depletion. The contribution of packaging is important for impacts, including global warming, fossil fuel depletion and human toxicity. The main hotspots for types of meal are the ingredients, waste and cooking method chosen by the consumer. Using instead of conventional ingredients leads to higher impacts. Sourcing chicken and tomatoes from and Spain, respectively, reduces environmental impacts of the meals compared to sourcing them the UK, despite the long-distance transport. The findings of the study are used to make recommendations to producers, retailers and consumers on reducing the environmental impacts from food and consumption.