Potential for improving the carbon footprint of butter and blend products

Discipline: carbon footprint; Keywords: GHG emissions, vegetable oil, fat content, type of packaging. 

Climate change and the associated reduction in carbon footprint are currently much in the limelight, and for good reasons. It is becoming crucial that countries should put measures in place to limit greenhouse gas (GHG) emissions and all sectors (e.g. dairy) should contribute. In South Africa we have put a limited amount of thinking into calculation methodology in the Dairy Sector and even less in mitigation actions. Therefore it is interesting to take note of the results of a study in Denmark published by Dr A. Flysjo in the Journal of Dairy Science, No 12 of Volume 94 of 2011, page 5833 to 5841, where he calculated the carbon footprint of butter and butter-blend products. The title of the paper is: Potential for improving the carbon footprint of butter and blend products.

The food industry is a major contributor to global anthropogenic GHG emissions and is increasing proportionally, because of population growth and increasing demand for livestock foods which by and large have a larger carbon footprint than plant foods. Efforts to reduce emissions have emphasized a whole value chain approach and life cycle analysis, in other words if butter is the product all emissions on farm to produce the milk should be accounted for in addition to the manufacturing, packaging, transport etc of the butter until it reaches the retailer shelf. A number of countries and companies have gone through the exercise to map the carbon footprint of their products. Companies which come to mind are Aria Foods in Denmark, Fonterra in New Zealand, Unilever in The Netherlands and Nestlé in Switzerland. No doubt there have been similar efforts in South Africa, but the information is not readily available. Retailers are also beginning to place high emphasis on the carbon footprint of products, for example Walmart has initiated the Sustainability Consortium, where the food industry meets to develop guidelines on how to assess the environmental impact of products, and Tesco (UK) and Casino (France) have begun to label dairy products with carbon footprint values which makes it possible for the consumer to make an informed choice.   

In this study the author analyzed the carbon footprint of butter and butter-blend products containing vegetable oil, with the focus on fat content and size and type of packaging. The products analysed were butter with 80% fat in 250g wrap, 250g tub and 10g mini tub, and blends with 80% and 60% fat (both containing about 70% butter and 30% vegetable oil) in 250g tubs. Life cycle analysis was used to account for all GHG emissions from cow to consumer. A critical aspect in such calculations is how emissions are allocated between different products which as yet have not been solved satisfactorily. The author allocated the raw milk between the products using the weighted average between fat and protein content, based on the price paid for raw milk to dairy farmers in Denmark.

The carbon footprint (expressed as carbon dioxide equivalents, CO₂eq) for 1 kg of butter or blend ranged from 5.2kg for the blend with 60% fat to 9.3kg CO₂eq for butter in the 250g tub if no waste at the consumer level is assumed, and 5.5kg for the blend with 60% fat to 14.7kg CO₂eq for butter in the mini tub when waste at the consumer level is taken into account. The results showed that fat content, the inclusion of vegetable oil and waste at the retailer shelf with mini tubs had the greatest influence on the carbon footprint of the products. With regard to fat content and the inclusion of vegetable oil, the results suggest that if the same functionality as butter can be retained while shifting to lower fat and higher proportions of vegetable oil, the carbon footprint of the product will be decreased. In the study size and type of packaging were less important, but nevertheless it is important to have the correct size and type of packaging to avoid unnecessary losses at the retailer shelf. The greatest share of GHG emissions associated with butter production, and it would be the case for all other dairy products, occurred at the farm level. This is because of the GHG emissions of the cow herself through enteric fermentation, manure and nitrogen fertilizer of pastures. This study showed that relatively small improvements at the farm level can yield high benefits for the final product, for example a 5% reduction in emissions at the farm level was more beneficial than a 50% reduction in energy use at the dairy plant.    

Bottom line: Although everybody in the dairy value chain should contribute to lowering the carbon footprint of dairy products, the farmer can contribute the most. This is also not difficult: the factors contributing the most are milk yield (improvement with higher yields per cow and more efficient production), less dry cows, shortened calving interval and improved nutrition (effective feed formulation). These factors are management related and therefore in the control of the farmer.