The US Department of Agriculture has picked the organisations that will put seals of approval on US organic practices, farms and distributors and the products that they sell.

In the department's goal of coming up with a national 'organic' definition, all of the country's agricultural products labelled organic must, by this autumn, originate from farms or handling operations certified by a USDA-accredited agency.

Called the National Organic Program (NOP), it will detail the methods, practices and substances that can be used in producing and handling organic crops and livestock, as well as processed products.

Forty-two local, state and foreign organisations have been accredited to act as certifiers of the products.

By Philip Fine, just-food.com correspondent