Combined effects of temperature, pressure and low pH on the amplification of DNA of plant derived foods

Abstract

The effect of food processing on the DNA integrity was studied by means of PCR amplification of soybean, transgenic MON 810 and non-transgenic maize, bean, and pea. The degree of DNA degradation was checked by PCR and visualised by agarose gel electrophoresis. The conditions of technological treatment such as temperature, pH, pressure, and their combination may negatively influence the integrity of DNA in processed foods and hence PCR detection of food components. The DNA over 300 bp was amplifiable when mild processing parameters up to 100°C were performed at approximately neutral or low acidic pH. The autoclaving (12°C; 0.1 MPa) significantly reduced the size of amplifiable DNA in the time dependant manner and that was intensified by acidic pH. The maximum amplicons length achieved for highly processed matrices was 300 bp. The major impact on the DNA integrity was exerted by the combination of pressure, temperature, and low pH.