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A B S T R A C TConcentrations of the major jlavonoids and phenolic acids in the peel und cortex of fiuit of eight commercial apple cultivars were determined by H P L C . The multivariate statistical technique of correspondence analysis was applied to the polyphenol profiles to describe distinctive groups of cultivars and of polyphenois, and their joint correspondences.Cultural and growing conditions had u limited eflect on the polyphenol profiles of the cortex and peel. Chlorogenic acid was the principal polyphenol in the cortex with the lowest levels being in Red Delicious and the highest in Jerseymac, which were compensated by changes in phlorizin. Cortland had low levels of' chlorogenic acid and Gravenstein had high levels, but these were oflset by the levels of catechins.The quercetin, rhamnoside, was the principal phenolic compound for the peel data with low levels in Red Delicious, Cortland, Spartan and Jerseymac and high levels in Golden Delicious, Gravenstein and Northern Spy. Levels of chlorogenic acid, offset by levels of phlorizin and catechins, distinguished between Red Delicious and Cortland. Rutin was important in distinguishing between Jerseymac and Spartan.

The flavonoid glycosides of Spartan apples were isolated by column chromatography on polyamide and Sephadex resins and by RP-HPLC. They were characterized by and 13C NMR as phlorizin and the following glycosides of quercetin: -L-arabinofuranoside, d-D-galactopyranoside, /3-D-glucopyranoside, -L-rhamnopyranoside, /3-D-xylopyranoside. The coupling constants in the XH NMR spectra were used to establish anomeric configurations of all glycosides.

In a series of exploratory experiments, storage of McIntosh apples (M&s domestim Borkh.) in modified atmospheres (MA) (5% CO2

Postharvest response of wild lowbush blueberry (Vaccinium angustifolium Ait. and V. myrtilloides Michx.) to mechanical damage and storage temperature was studied during 2 years. Fruit weight loss and the incidence of shriveled or split berries were major components that contributed to the loss of marketable yield resulting from mechanical damage and storage temperature. Decay of berries resulted in only 1% to 2% of the total marketable fruit loss. In general, the major quality attributes (firmness, microbial growth, hue, bloom, split, and unblemished berries) deteriorated with increasing damage levels and increasing storage temperature without significant interaction. Temperature had consistent effects in both years on moisture content, soluble solids concentration, titratable acids, weight loss, shriveled and decayed berries, Hunter L values, and anthocyanin leakage, while damage level had inconsistent or no significant effect.

Storage of ‘McIntosh’ apples (Malus domestica Borkh.) in low O2 atmospheres (1.5% CO2 + 1.0% O2) maintained fruit firmness by an average of 0.86 kg over 40 grower lots, compared with the same fruit stored in conventional controlled atmospheres (5% CO2 + 2.8% O2). Low O2 storage resulted in fruit which were higher in titratable acids and were significantly crisper, more acid, and juicier to sensory panelists. Fruit maturity at harvest was a significant factor in determining the losses of firmness and titratable acids in low O2 storage.

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