Differences between mineral analyses from cork spotted and extra fancy 'Anjou' pear fruit

Graduation date: 1988The feasibility of using a post harvest sampling time for\ud fruit testing in Anjou pears was evaluated. The goal was to\ud determine if a simple and rapid analysis of fruit tissues could be\ud useful in identifying potentially weak fruit that could be\ud marketed before the onset of the storage disorder cork spot.\ud A packing house study was conducted in 1985 and 1986 which\ud compared mineral analyses from extra fancy grade Anjou pears with\ud the like analyses from cork spotted Anjou pears. Samples were\ud divided into six different tissue types; cores, tangential slices\ud with and without peels, the peel itself, interior cortical plugs,\ud and exterior cortical plugs. Mineral concentrations were expressed\ud on both a dry weight and fresh weight basis. Ratios between\ud elements were also evaluated.\ud It was determined that any of the six different tissues could\ud be used for the purpose of separating extra fancy grade fruit from\ud cork spotted fruit. There is a real concentration difference\ud between cork spotted and extra fancy pear fruit that is not size\ud related, although size does affect mineral concentrations. The\ud peel of the fruit was the most convient tissue to analyze and\ud provided the best separation between disordered and normal fruit.\ud Differences between dry or fresh weight expressions were minimal.\ud A nitrogen to calcium ratio was the best index to use for\ud separation of the two catagories of fruit.\ud Post harvest mineral analyses may be useful in light of\ud considerable literature relating pre-harvest mineral\ud concentrations to post harvest storage problems. A post harvest\ud evaluation of peel tissue could greatly simplify collection and\ud processing of fruit samples compared to pre-harvest collection and\ud analysis of cortical tissue commonly utilized in apple testing