Evaluation location: Georgia, United States
A minimum of 10 mature fruit in sound condition were harvested from several plants at random. Every reasonable effort was made to select representative fruit from various positions on the plant(s). Stems and calyxes were removed and entire fruit were ground to a slurry in a commercial food processor (meat grinder). The resultant slurry was frozen and stored at -4C until used (but less than 3 months). Ten grams of the fruit slurry was weighed and added to a 250ml beaker. To the slurry was added 40ml of 100% reagent grade MeOH. This mixture was homogenized for two minutes using a Tekmar Tissuemizer Model SDT 1810 with model TR-10 power controller at setting 70. The contents of the beaker were subsequently transferred to a 50ml polypropylene screw top centrifuge tube and centrifuged @ 15,000 x g for 10 min at 20C. The clear methanol extract was transferred to a screw-capped glass vial (amber) and stored at 4C in the dark. Dilutions of each sample (1:10, 1:100, 1:1000 and 1:10000, v/v) to be analyzed were prepared using 10% methanol. Procedures for the EIA plate preparation and analysis are as described in the literature accompanying the assay kit (Beacon Analytical, Portsmouth, ME). Jarret, R.L. et al 2003. Journal of Food Composition and analysis. 16:189-194. Perkins, B. et al. 2002. Journal of the AOAC International. 85:82-85.