Examination of cause of failure to taxon-specific DNA was not detected from bifun (rice vermicelli) using processing model experiment]

In the inspection of genetically modified rice, rice taxon-specific DNA could not be detected in processed rice food (bifun: rice vermicelli). The effects of using PCR the ratio of rice powder content and temperature of processing on the detection of taxon-specific DNA were examined by means of processing model experiments using cornstarch with 0, 2, 5, 10% rice powder by weight. Cornstarch and rice powder were blended with water and subjected to heating, steam-treatment, and autoclaving. The rice taxon-specific DNA was detectable in 2% rice powder following heat and steam treatments. After autoclaving, rice taxon-specific DNA was detected only in the 10% rice powder product. In the processing model experiment using rice powder, it was found that autoclaving caused severe DNA degradation.