A GMO labeling battle is rumbling in the United States, with those demanding full disclosure of genetically modified organisms in food products pitted against big companies.
Although some giants such as General Mills have recently taken timid steps toward being more upfront with consumers, the United States, unlike some 60 other countries, lacks a legal requirement to do so.
Still, in the world's largest economy, where almost all soy, sugar beet, corn and canola crops are genetically engineered, bills requiring labeling for GMO foods were introduced in 26 states last year.
But only Maine and Connecticut approved such measures and have yet to implement them.
Alaska adopted a law in 2005 requiring labeling of genetically engineered salmon, whose safety for human consumption is still being studied by the US Food and Drug Administration (FDA).
Elsewhere measures have been defeated, notably in the state of Washington, where voters narrowly rejected GMO labeling. Other proposals are near death or languishing in legislative committees.
But supporters of GMO labeling of food insist they are unfazed and determined to shore up more support.