The research found that growers supplying supermarkets in northern Europe are under more pressure than companies supplying the European wholesale sector and supermarkets in France and southern Europe.

The PIP researchers found a marked variation among ACP countries, often depending on the destination market for the produce. Kenya, Zambia and Ghana, which sell predominantly into northern European multiples, have faced more stringent demands from buyers and from an earlier date, the survey said.

In Kenya, many companies were already obliged to be EurepGAP certified by 2005, while southern European customers and the wholesale sector more generally in Europe had applied less pressure for compliance on exporters until ramping up expectations in 2006-07.

A spokesperson for PIP, which is run by EU-ACP liaison committee COLEACP, said: “In Kenya, which has been under more pressure (and for longer) from the high-value retail sector, there is a decrease in sourcing from smallholders in real terms. The pressures experienced as a result of certification, and the changes it appears to be provoking in procurement practices, are likely to be felt soon in other countries, where certification is now rolling out.”

The study found that, despite the fact that they are in many respects operating at a disadvantage, ACP exporters and small-scale growers have demonstrated that compliance with regulatory and market demands - from MRLs and traceability to more stringent standards - is achievable.

However, for many smallholders, while compliance to standards such as GlobalGAP is possible, certification on a sustainable basis is not, because it is not cost-effective.

The survey concludes that the difficulties faced by ACP suppliers in meeting buyer demands need to be addressed in terms of the technical demands needed to achieve compliance, but also the cost constraints associated with proving compliance through certification, and the sustainability of certification over the long term.