According to a Yahoo article, many foods are not exactly what we think, and store brands or "off" brands are more likely to have fraud than trusted brands. One reason is the source of those low-priced or store brands, often from foreign countries. Remember the toxic non-food additives we heard about in baby formula from China? Read the article and decide for yourself.
"Currently, imports account for 85% of seafood, 39% of fruits and nuts and 18% of vegetables. That leads to great variety, but also increased risk from less rigorous food safety practices in other countries, says Clare Narrod, the risk analysis program manager for the University of Maryland...."