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Understanding theGHG impacts of food preparation and consumption in the home. Phase 2 - FO0409

There is increasing market interest in understanding the contribution that products and services make to climate change. In response, DEFRA and the Carbon Trust are currently working with the British Standards Institution (BSI) to develop a methodology that will enable organisations to understand the greenhouse gas (GHG) emissions associated with the products that they manufacture, buy or sell. With this knowledge, the GHG performance of these products can be more effectively improved. The BSI is developing a Publicly Available Standard (PAS) that will provide an agreed, accurate and consistent approach to measuring GHG emissions associated with products and services. The PAS will also provide a tool to explore the impacts of potential future scenarios for food production and consumption, including combinations of different systems of farming, food processing and distribution.

The project is intended both to establish the suitability of the developing BSI-PAS methodology for generating robust data on GHG impacts of storage and cooking practices in-home and to generate robust GHG impact data on a range of specific food types and meal constructs. This will inform DEFRA on the relative GHG importance of activities in this sector of the food chain and also form the basis of future messages to consumers to help improve their environmental footprint in future. It is envisaged that work would consist of two fairly distinct elements:
1. a brief evaluation of the suitability of the BSI methodology in the in-home context, followed by
2. a more lengthy study to generate real GHG impact data on a range of foods and food handling methods.

In the context of this project, food storage and preparation will be taken to include frozen, refrigerated and ambient storage and a range of cooking methods such as gas and electric ovens and hobs, microwaves etc. It will also take account of the impacts of associated energy requirements such as the:
- use of food processors or other kitchen equipment,
- heating of water for washing up,
- generation of GHG from waste food and packaging materials

The project will be undertaken in two phases. This project is concerned with phase 2.

Phase 2 will obtain detailed calculations of GHG emissions based on food storage and preparation in the home. Initially this will use the two part prepared meal (i) a cottage pie, made from beef mince, tomatoes and potatoes, and can either be purchased from a retailer in a ready-to-eat format (frozen, chilled, ambient) or prepared from ingredients in the home, and (ii) an apple crumble, made from fresh apples, flour and butter. Phase 2 will obtain data on the different cooking practices in the home and how this impacts on GHG emissions. The scope of the work will be expanded to include the following:

- application of PAS2050 to a wider range of foods and meal types and a variety of potential cooking methods to generate robust data on the potential impacts of possible scenarios. This will include cooking of fresh meat, fresh vegetables (e.g. potatoes, carrots), baking of bread, and production of prepared dishes (e.g. cottage pie and apple crumble).

- assessment of the relative impacts of home preparation of meals from individual raw materials compared to the purchase and home cooking of an equivalent ready meal or prepared food (e.g. cottage pie and a supermarket white loaf of bread).

- consideration of the waste implications of various in-home storage and cooking practices (e.g. effects of buying larger amounts of raw materials than required, treatment of plate waste, issues around types and sizes of food packaging). Data will be generated to compare with the corresponding waste issues from buying in prepared ready meals. The project team will access recent reports from WRAP as the starting position (

- impact of packaging on the GHG emissions. Packaging may be a potentially significant contributor to GHG emissions from waste materials.
Project Documents
• Final Report : Understanding the GHG impacts of food preparation and consumption in the home   (602k)
• Other : Cottage Pie Case Study   (318k)
Time-Scale and Cost
From: 2008

To: 2008

Cost: £34,428
Contractor / Funded Organisations
CCFRA Technology Ltd
Food Chain              
Global Warming              
Method Development              
Methodologies/forecasting tools - data collection              
Resource efficient and resilient food chain              
Sustainable Farming and Food Science              
Fields of Study
Resource Efficient and Resilient Food Chain