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Several sweet cherry (Prunus avium L.) cultivars were stored in air or modified-atmosphere packages (MAP) at 1 °C for 2 or 4 weeks, respectively. The new cultivars included `Santina', `Sumpaca Celeste', `Sumnue Cristalina', `Sumste Samba', `Sandra Rose', `Sumleta Sonata', and `Skeena', and the standards were `Lapins', `Sweetheart', and `Bing'. Fruit were rated for defects (stem browning, stem shrivel and fruit surface pitting), and fruit quality at harvest and after storage. Weight loss during storage was influenced by year, storage treatment, and cultivar. Stem shrivel, stem browning, and fruit surface pitting varied among cultivars and years. Generally, fruit stored in MAP had higher fruit firmness than at harvest or when stored in air. The respiration rate of fruit was lower in later than in earlier maturing cultivars, but respiration rate at harvest was not related to any of the quality measurements taken after storage.

Sweetheart ' cherries were sealed in peiforated or nonperforatedpolyethylene bags and stored for 6 weeks in air at OC. Samples were removed after 1, 2, 4 and 6 weeks of storage and evaluated for fruit and sensory quality. Volatile analyses were done on samples kept in storage for 2, 4, 6, 8 and 9 weeks. Atmospheres afrer 6 weeks of storage were approximately 4.6% 0, and 10% CO, for the peiforated bags (1993) and 6.6% 0, and 3.5% CO, for the non-peiforated bags (1994). Fruit brightness (L* value), firmness and titratable acidity declined during storage. Skin color (hue angle) decreased slightly in redness over the 6-week storage period. Sensory evaluation in 1993 showed a decline in fruit appearance and flavor with storage duration. Texture and juiciness did not change. Acceptability remained high for the first 4 weeks of storage. Twenty-seven volatiles were identified by head-space analysis (I 993). Little change occurred in volatile production except for acetaldehyde which increased sharply from week 2 to 4 and ethanol which increased sharply between week 8 and week 9. Butyl acetate behaved much like acetaldehyde. Modified atmosphere packaging maintained high fruit luster and green stems. No differences in fruit quality were observed with bag type, but storage appears to be limited to 4 weeks for 'Sweetheart' cherries because offlavor loss.

Fruit were studied to determine if anatomical and physiological features explain the difference in susceptibility to rain-induced cracking of the sweet cherry (Prunus avium L.) cultivars Sue (resistant), Lapins (moderately resistant), and Van (susceptible). Water uptake as a percentage of fruit weight at cracking tended to be high in `Sue', medium in `Lapins', and low in `Van' and was related to the percentage of cherries remaining sound after 4 hours of immersion, suggesting that this trait is a factor in determining resistance. Mesocarp cells of `Sue' were more rectangular in section than those of the other cultivars. Skin elasticity and thickness of the cuticle did not explain resistance of `Sue' to cracking. Magnesium, copper, and phosphorus mineral contents were not related to cracking susceptibility, but the content of calcium, which influences cell wall integrity, in the epidermis of `Sue' was lower than in `Van'. Calcium content was not different in the hypodermal cells of the two cultivars. None of the anatomical features examined in this study explain the resistance to fruit cracking of `Sue'.

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