This papers show how the LCA team at Unilever has gone about task of trying to calculate the GHG footprint of its Knorr product range by main product types.
Knorr is one of the world’s largest food brands, and the largest Unilever brand, with a presence in approximately 90 countries. Its product portfolio includes dry and wet soups, bouillons and sauces, fruit and vegetable shot drinks as well as frozen meals and ‘meal-makers’ (i.e. seasoning mixes for specific dishes, e.g. stir fries, stews, casseroles, etc.).
There are over 7,500 different ‘stock-keeping units’ (SKU: product/packs reflecting individual recipes, pack sizes and formats). Knorr product supply chains are global with many thousands of ingredients sourced from around the world.
The paper (Milà i Canals L, Sim S, García-Suárez T, Neuer G, Herstein K, Kerr C, Rigarlsford G and King H (2011) 'Estimating the greenhouse gas footprint of Knorr'. Int J Life Cycle Assess Vol 16 pp50–58) raises questions as to the usefulness and accuracy of on-pack carbon footprint labels.
Abstract
Purpose
Greenhouse gas (GHG) emissions have been identified as one of Unilever’s priority environmental impact themes: this assessment was therefore conducted to help the Knorr brand measure and understand the GHG emissions related to its product portfolio, identify opportunities to manage GHG emissions in the Unilever-owned operations (manufacture) and influence managed reductions elsewhere in the Knorr product lifecycles, and assess the impact of the brand’s innovation and portfolio strategies on its GHG footprint.
Methods
A bottom–up product-based life cycle assessment (LCA) approach was considered impractical to assess Knorr’s portfolio’s complexity. Thus, a meta-product-based accounting LCA approach was followed. Up to 16 product types or “meta-products” were assessed in each geographical region, with a total of 36 meta-products assessed globally. Then, the Knorr GHG footprint was derived by multiplying the impacts calculated per tonne of each product type with the sales volumes in 2007. Data for ingredients and processing technologies were gathered from the literature and suppliers; data from Knorr factories were used for the manufacturing stage. The variability in ingredients’ production and processing and in manufacture was factored in and propagated through the calculations to assess the robustness of the results.
Results
The profiles of different meta-products within a product group (e.g. dry soups) follow similar patterns in terms of absolute GHG per tonne and distribution of such emissions along the life cycle. Variations are observed due to recipe composition and electricity mixes in the different regions. The range of variability around absolute results is significant and varies between meta-products. Aggregating the results for individual meta-products with their production volumes, the global Knorr brand GHG footprint in 2007 was estimated to be in the region of 3–5 million tonnes CO2e/annum (95% confidence interval). In spite of the significant variability ranges found, the results are useful for target setting and identification of opportunities for improvement.
Conclusions
This is the world’s first life cycle GHG assessment at brand’s product portfolio level. The meta-product approach simultaneously allows for the assessment and comparison of individual product types as well as for the estimation of a brand’s total GHG. The variability assessment enhanced robustness of the results by identifying a confidence range; given the complexity of the studied supply chains and the current data quality translated in wide confidence ranges, single number on-pack carbon labels seem questionable and not robust enough to inform consumers.
You can download the paper here.
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