Acid test

Evonik’s Michael Binder gives an insight into the Life Cycle Assessment of the essential amino acids Methionine, Lysine and Threonine in animal nutrition.

In the public mind there is an ongoing debate about the environmental impacts of farming and intensive livestock production. Also there is a beneficial and open-minded discussion about the environmental benefits and costs of chemical production for the food chain.
Providing these intensive discussions with detailed information contributes to a sustainable comprehension of the advantages of the production of supplemental essential amino acids covering both the significant improvement of feed and food quality and the sustainable reduction of environmental pollution.

Therefore the question as to the potential of the chemical industry for environmental protection seems to be a viable and worthwhile one. A better understanding of the ecological synergy effects between sustainable production in the chemical industry, environmental protection and welfare of animals and final consumers is needed.

The Life Cycle Assessment methodology represents an international scientific standard for the evaluation of all impacts resulting from technical production processes. Also the impact of agriculture on the environment is an interesting topic due to ecological health and natural resources. In general, the impacts of agricultural are well known and a set of agri-environmental indicators have been designed for an effective monitoring of renewable raw materials.

Amino acids are building blocks of proteins and thus all life. They are important elements of the nutritional value of feed ingredients. Methionine is the first limiting amino acid in poultry nutrition and is produced by synthesis from petro-chemical raw materials, whilst for Lysine, the first-limiting amino acid in pig nutrition, production is based on biotechnology with renewable raw materials. Threonine, the next important essential amino acid in animal nutrition, is also sourced by modern biotechnology.

Today, Life Cycle Assessments (LCA), based on diets with identical nutritional value as the functional units, can compare the use of supplemental amino acids in animal nutrition with equivalent amounts of these essential building blocks from natural protein sources such as soybean meal and rapeseed meal.

The overall principle applied in LCAs is the comparison of substantially equal feed sources. That means two options are always drawn to provide the same nutritional recommendations of the animals. One option covers the nutritional demand of essential amino acids through natural sources such as soybean meal or rapeseed meal. The other provides the same amount of nutritionally recommended amino acids by synthetic sources.

Additional quantities of domestically or locally produced wheat is added to balance the energy content of the different diets. Thus, 118 kg wheat supplemented with 1.0 kg of an amino acid premix consisting of methionine, lysine and threonine can substitute 119 kg of a feed based on soy meal and soy oil, or alternatively 126 kg wheat supplemented with 1.0 kg of an amino acid premix will substitute 127 kg of a feed based on rape seed meal, rape seed oil and soybean meal.

An independent Life Cycle Assessment on greenhouse gas emissions from the use of supplemental methionine was recently conducted by the International Council of Chemical Associations (ICCA) in collaboration with McKinsey. The common procedure of the ICCA-approach was to identify a specific ratio between emissions caused by chemical production and the overall savings of emissions during the application of the specific chemical substances during their product life. This demonstrated that globally for each 1 metric ton of CO₂ emitted during the synthesis of methionine, in total 23 metric tons of CO₂ emissions can be saved over the product's life cycle. The basis of the calculation is the worldwide use of about 750,000 mt methionine which is the actually assumed market volume for DL-Methionine.

The area of eutrophication is another important environmental impact category, the use of supplemental methionine in broiler nutrition shows further impressive results: worldwide ammonia emissions can be reduced by 26 metric tons per ton of NH3 emitted in production as well as 7 metric tons of nitrate per ton of NO3- caused by production.

Michael Binder studied Technical Biology at the University of Stuttgart focussing on Biochemical Engineering and Industrial Genetics. He obtained a PhD in Technical Microbiology from the same institution. He is currently employed at Evonik Degussa GmbH working in the field of Feed Additives, Research & Development Biotechnology lateron Marketing and Regulatory Affairs.