Unilever and Ahold have become among the first companies to acquire certificates for sustainable soy.

The purchase - made by a number of Dutch companies under the local Initiative for Sustainable Soy (IDS) - was of the first batch of soy certified by the Round Table on Responsible Soy (RTRS).

The RTRS was set up in 2006 to draw up criteria for the sustainable cultivation of soy, which is used in animal feed and in a swathe of food products.

The companies, which also include dairy processor FrieslandCampina and meat firm Vion, have purchased certificates for 85,000 tonnes of RTRS-certified soy from Brazilian producer Grupo André Maggi. The Brazilian company had its first soy fields certified by independent auditors in May.

"This first-ever certification of a producer, and the subsequent market uptake are important milestones for the RTRS, which began its quest to become the global standard for responsibly cultivated soy in 2006. Respecting the land rights of local communities and preventing the degradation of valuable nature areas are among its objectives," a statement from the Dutch Sustainable Trade Initiative said.

The system works on a similar basis to certification schemes for palm oil, where food manufacturers and retailers buy certificates to encourage producers to move to sustainable production.

The actual soy used is made conventionally but, as a spokesman from the Dutch Initiative Sustainable Trade, the costs of sourcing truly sustainable soy are prohibitive and much of the cost would go to a company's distributor, rather than the grower, As more certificates are purchased, the spokesman explained, soy producers should move to sustainable production and it would become "cost-efficient" for manufacturers to have a "direct link" to the grower, the spokesman added.

Unilever, which uses soy in spreads and mayonnaise, has said the move was "a small step" towards sourcing 100% of its agricultural raw materials in a sustainable way by 2020.

On soy, Unilever said last year that it would look to source all its soy beans sustainably by 2014. Its soy oil would come from sustainable sources by 2020. The targets were part of Unilever's Sustainable Living Plan, which was published in November.

Announcing Unilever's purchase of the certificates for sustainable soy today (8 June), chief supply chain officer Pier Luigi Sigismondi said: "Certification is an essential first step towards sustainably grown soy and sourcing sustainably grown soy will help Unilever meet the environmental commitments in its Sustainable Living Plan. That's why this first batch is so significant, both for the RTRS and Unilever."

Agustin Mascotena, executive director of the RTRS, added: "The purchase of soy credits by IDS marks a very important step in the transition to a responsible international soy value chain."