2.5. DNeasy Mericon Food Kit (Qiagen Method)

The Qiagen method was conducted using DNeasy^® mericon™ food kit (Qiagen GmbH, Hilden, Germany) following the manufacturer’s instructions with slight alterations. Each EBN of 25 mg was vortexed with increased volume of 1.3 mL food lysis buffer and 5 µL proteinase K, and then incubated for a longer period of 1 h at 60 °C to enhance inhibitor precipitation. The following extraction procedures were proceeded with the manufacturer’s instructions until the elution step, where DNA was eluted from QIAquick spin column with 100 µL of buffer EB instead of 150 µL for standardisation purpose. The Qiagen method lyses with non-ionic detergent CTAB and proteinase K, and binds DNA to silica membrane in spin column.