Effects of storage temperature and atmosphere on saskatoon ( Amelanchier alnifolia Nutt.) fruit quality, respiration and ethylene production

• Published in: Postharvest biology and technology 1998-06, Vol.13 (3), p.183-190
• Main Authors: Rogiers, Suzy Y., Knowles, N.Richard
• Format: Article
• Language: English
• Subjects: ALMACENAMIENTO ATMOSFERA CONTROLADA; AMELANCHIER; Amelanchier alnifolia; APTITUD PARA LA CONSERVACION; APTITUDE A LA CONSERVATION; BAYAS; CONTROLLED ATMOSPHERE STORAGE; ETHYLENE PRODUCTION; Fruit quality; KEEPING QUALITY; PETITS FRUITS; PRODUCCION DE ETILENO; PRODUCTION D'ETHYLENE; RESPIRACION; RESPIRATION; Saskatoon fruit; Serviceberry; SOFT FRUITS; STOCKAGE EN ATMOSPHERE CONTROLEE; TEMPERATURA; TEMPERATURE
• ISSN: 0925-5214; 1873-2356
• DOI: 10.1016/S0925-5214(98)00012-X

Low temperature and controlled atmospheres (CA) were tested for their effectiveness in extending the storage life of saskatoon fruit. The quality of fully ripe (purple) `Smoky' and `Pembina' fruit was assessed over 40 days of storage at 0.5 or 4.0°C in humidified (95% RH) air. Fungal colonization, fruit softening, fresh-weight loss, and anthocyanin degradation were substantially lower in fruit stored at 0.5°C than in that stored at 4.0°C. `Smoky' fruit maintained higher soluble solids when stored at 0.5°C than at 4.0°C, but that of `Pembina' was not affected by temperature. Decreasing the O 2 concentration from 23 to 5.8% had little effect on fruit respiration at 23°C; however, the respiration rate fell about 26% as the O 2 concentration was lowered from 5.8 to 1.7%. A 2% O 2 atmosphere was above the extinction point for aerobic respiration at 23°C. Fruit (cvs. `Smoky' and `Northline') of maturity classes seven, eight and nine were stored in 2, 10 or 21% O 2 (0.035% CO 2) at 4.0°C (95% RH), and respiration and ethylene evolution were monitored over 10 days. The rate of ethylene production by fruit of both cultivars decreased linearly with advancing maturity class and with declining O 2 concentration. Furthermore, the increase in ethylene production rate of maturity class nine (fully ripe) fruit with increasing O 2 concentration was less than that from fruit of maturity classes seven and eight. Respiration rates of `Northline' and `Smoky' fruit were equal at 21% O 2, but `Northline' fruit had a 15% lower respiration rate than `Smoky' fruit at 2% O 2. Collectively, our results show that storage at 0.5°C was more effective than 4.0°C at maintaining fresh quality of saskatoon fruit. Low O 2 atmosphere (2%) effectively slowed ethylene production and fruit respiration and thus may be a beneficial adjunct to low-temperature storage.