For some apple varieties, beware of CO2 accumulation in storage rooms during loading is important

The objective of this study was to investigate the development of external CO2 injury in ?Empire? apples during storage room loading. Effects of cooling rate and SmartFresh were also studied. ?Empire? apples were harvested from an orchard near Simcoe (ON) during the commercial harvest period. Fruit were transported to the Apple Research Storage Lab in Simcoe within one hour of harvest. Half of the apples were rapidly cooled to 3?C, while the others were slowly cooled from ~22?C down to 14-16?C overnight. Half of the ?Empire? at each temperature were also treated with SmartFresh (1 ppm, 1-MCP) overnight. After 24 hours, all apples were held in ~17% O2 + 4% CO2 at 3?C for one, two or four weeks. These scenarios were intended to mimic the build-up of CO2 during commercial room loading before the establishment of controlled atmosphere. Upon removal from storage, fruit were allowed to warm to room temperature and then evaluated for quality that day. Results?Empire? fruit started to exhibit external CO2 injury after only one week of storage and there were significant increases after two and four weeks . Slow cooling increased the incidence of CO2 injury and the disorder appeared sooner, compared to fruit cooled rapidly. As expected, SmartFresh also increased incidence of CO2 injury. Previous work showed ?McIntosh? developed little external CO2 injury before four weeks of storage with 4% CO2 (data not presented). Furthermore, Summerland ?McIntosh? was more susceptible to CO2 injury than Pioneer, suggesting that there is different sensitivity among strains. These results indicate that storage operators should be cognizant of CO2 accumulating during the loading of storage rooms, especially with ?Empire? apples. This cultivar is extremely sensitive to CO2. The use of diphenylamine (DPA) will reduce the development of external CO2 injury. This project is part of the Canadian Agri-Science Cluster for Horticulture 2 program, supported by Growing Forward 2 with Agriculture and Agri-Food Canada and the Canadian Horticultural Council. Thanks to the Ontario Apple Growers, Apple Marketers? Association of Ontario, Les producteurs de pommes du Qu?bec, BC Fruit Growers? Association, AgroFresh Inc., Storage Control Systems Inc., GRB Ag. Technologies Inc., and Decco US Post-Harvest Inc. for their financial support; as well as to Behrouz Ehsani-Moghaddam and Lorie Walker for their technical assistance; and Norfolk Fruit Growers? Association and Jeff Cassidy for their direct collaboration. Dr. Jennifer DeEll is fresh market quality program lead for horticultural crops, OMAFRA, based in Simcoe, Ontario. The picture shows External CO2 injury in ?Empire? apple. Source Beware of CO2 accumulation in ?Empire? apple storage rooms during loading, Dr. Jennifer DeEll, www.thegrower.org (link below)More informationElevated carbon dioxide in storage rooms prior to establishment of controlled atmosphere affects apple fruit qualityJennifer R. DeEll, , Geoffrey B. Lum & Behrouz Ehsani-MoghaddamOntario Ministry of Agriculture, Food and Rural Affairs, Box 587, Simcoe, Ontario N3Y 4N5, CanadaPostharvest Biology and Technology, Volume 118, August 2016, Pages 11?16 Key wordsPoscosecha?? ?postcosecha?? ?postharvest?? ?na-oes?? ??? ??? ???????? ????? ??? ?post-r?colte?? ????? ?? ??????????? ??? ?na-oogst?? ?post-raccolta?? ?Obr?bka po?? ?p?s-colheita?? ????????????????? ?hasat sonras??? ??? ?Ernte?? ????????????????? ????? ????????????? ?postcollita?? ?poskliz?ov頠 ????? ??? ??? ??? ?nakon branja?? ?pozberov頠 ??? ?obdelovanje zemlje po?? ?post-colleita?? ?????? ??????? ?pascapanen?? ??il?onn postharvest?? ??????? ?p?c ra?as?? ?derliaus apdirbimas po?? ?lepas tuai?? ??? ?? ???????? ?post-recoltare?? ??????? ??????? ???????????????????? ?????????????? ?????????????????? ?sau thu ho?ch?? ?????????????????? ?zangemva kwenkathi yokuvuna Manzana?? ??? ?apple?? ??? ???????? ????? ??? ?pomme?? ??????? ?????? ?appel?? ?mela ?? ?jab?ko?? ?ma?㠠 ????????? ?elma?? ??????? ?Apfel?? ??? ???? ??