Division 1.1.2 F1

Collect the heel end cores in unused disposable containers which can be closed and/or sealed (in case containers are reused they should be thoroughly cleaned and disinfected using chlorine compounds). Preferably, the heel end cores should be processed immediately. If this is not possible, store them in the container, without addition of buffer, refrigerated for not longer than 72 hours or for not longer than 24 hours at room temperature.

Process the heel end cores by one of the following procedures: either,

1. (a)

   Cover the cores with sufficient volume (approximately 40 ml) of extraction buffer (Appendix 4) and agitate on a rotary shaker (50-100 rpm) for 4 hours below 24 °C or for 16 to 24 hours refrigerated,

   or

2. (b)

   Homogenise the cores with sufficient volume (approximately 40 ml) of extraction buffer (Appendix 4), either in a blender (e.g. Waring or Ultra Thurax) or by crushing in a sealed disposable maceration bag (e.g. Stomacher or Bioreba strong guage polythene, 150 mm × 250 mm; radiation sterilised) using a rubber mallet or suitable grinding apparatus (e.g. Homex).