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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.

A fumigation technique using brief exposure of fruit to a low concentration of acetic acid vapor was combined with modified-atmosphere packaging to reduce storage rots and increase shelf life of grapes (Vitis vinifera L.) and strawberries (Fragaria ×ananassa Duch.) by two or three times normal values. Both commodities were inoculated with spores of Botrytis cinerea Pers. before fumigation with acetic acid, packaging, and storage at lowered O2 levels. Fumigation with acetic acid at 8.0 mg·L–1 followed by modified-atmosphere packaging for 74 days at 0 °C reduced the percentage of rotted grapes from 94% to 2%. Strawberries fumigated with acetic acid at 5.4 mg·L–1 were free of decay compared to 89% rotted for the control fruit stored for 14 days at 5 °C.

Three prepackaging treatments were evaluated for ready-to-eat (R TE) lettuce. Fresh iceberg lettuce pieces were dipped for 3 min in cold water (4C) with 100 ppm total chlorine, warm (47C) water with 100 ppm chlorine and tap water at room temperature. The lettuce was dewatered by centrifugation, packed in breathable film bags (OTR: 1600-2000 cc/m2/24 h) and stored for 11 days at 1 C. Sensory evaluation revealed that the texture and visual appearance of stored RTE lettuce were improved by the warm water treatment. However, heat processing induced changes in the flavor of the lettuce, and a chlorinaceous ofl-odor was detected by some panelists.

Fumigation with acetic acid vapor to control decay of stored apples.Abstract -Introduction. Apples are potentially subject to blue mold decay caused by Penicillium expansum if stored at 1°C for three or more months or if wounded during handling. Results from trials with apples contaminated with conidia of P. expansum and fumigated in small chambers with acetic acid (AA) vapor indicated that fruit could be sterilized to reduce decay without effect on fruit quality. The objective of this study was to determine if larger quantities of apples treated with AA vapor would have less decay after storage and/or wounding. It was also important to determine if fumigation would affect apple quality and aroma. Materials and methods. Apple cultivars were harvested at commercial maturity for use in AA fumigation trials. Apples artificially or naturally contaminated with conidia of P. expansum were fumigated with AA vapor in a 1 m 3 gas tight chamber at 10°C for 1 h to 24 h or dipped in 450 µg thiabendazole × L -1 solution. Fruit fumigated in standard wooden or plastic apple boxes, or small wooden bins were either wounded and evaluated for decay after a week at 20 °C or stored at 1 °C for three or more months and evaluated for decay. Then apple quality was assessed. Results. Apples naturally contaminated with Penicillium spp. that had been stored at 1 °C in air storage and treated with AA vapour had 50% less decay than the control fruit. In another experiment, AA fumigation was as effective as thiabendazole in reducing decay. AA fumigation reduced decay of fruit coming out of storage for apples stored for 3 months, and a second AA fumigation reduced infection of wounds on these same apples. AA fumigation before storage did not affect apple quality or vinegar aroma. Discussion. AA fumigation showed great potential for reducing decay in stored apples. It could be used as an organic alternative to synthetic fungicides for control of blue mold decay. Canada / Malus (fruits) / postharvest decay / fungal diseases / Penicillium expansum / disease control / control methods / fumigation / acetic acid / thiabendazole / quality Contrôle de la détérioration des pommes stockées par traitement à la vapeur d'acide acétique.Résumé -Introduction. Les pommes sont potentiellement sujettes à la moisissure bleue provoquée par Penicillium expansum si elles sont stockées à 1 °C pendant 3 mois ou plus, ou si elles sont blessées pendant la manutention. Les résultats d'essais effectués avec des pommes contaminées par des conidies de P. expansum et fumigées dans un local restreint avec de la vapeur d'acide acétique (AA) ont montré que les fruits stérilisés pouvaient être moins détériorés, sans que leur qualité ne soit altérée. L'objectif de cette étude a été de déterminer s'il était possible de protéger de plus grandes quantités de pommes contre ces détériorations après stockage et/ou après blessures en les traitant à la vapeur de AA. Il s'agissait également de déterminer si la fumigation affectait la qualité et l'arôme des pommes traitées. Matériel et m...