At each sampling point, duplicate bags of controls and HHP-treated asparagus were homogenized in a stomacher for 30 s at maximum speed. Then, 1.5 ml from each bag was transferred to a sterile Eppendorf test tube. A 0.5 ml
portion of this suspension was serially-diluted in sterile 0.85% NaCl saline solution and plated in duplicate on Tryptone Soy Agar (TSA, Scharlab, Madrid) plates.
The plates were then incubated for 24 h at 30 °C for viable cell counts. The remaining cell suspension was used for DNA extraction and analysis as described below.