Determination of genetically modified corn and soy in processed food products

Article history: Received on: 07/04/2015 Revised on: 22/04/2015 Accepted on: 11/05/2015 Available online: 20/06/2015 Genetically modified organisms (GMOs) and their raw materials used in processed foods should be analyzed and labeled. The aim of our study was to evaluate the present situation of the food products and to determine appropriate DNA isolation method in processed food products. Keeping in view, there is a need to determine different DNA extraction protocols specific to processed foods and these protocols should be modified and must be applied to test GMOs. In this study, six different DNA extraction protocols and two DNA kits were used for soybean or corn based 12 kinds of products with total of 27 processed food products including biscuit, cornflakes, cracker, corn chips, corn starch, corn flour, popcorn, sweet corn, baby food, cake, compressed popcorn, soy flour along with positive controls (GM soy and GM corn). Obtained results showed that DNA quantity and quality varied with type of food and processing. Investigation of genetically modified organisms in these products was determined by qualitative PCR analysis. Molecular screening of these food products were carried out by using 35S promoter and nos or tnos terminator sequences. As a result, some of the products containing corn/soy based raw material were found to be genetically modified.