Time filter

Source Type

McCormick R.,Kompetenzzentrum fur Obstbau Bodensee KOB | Neuwald D.A.,Kompetenzzentrum fur Obstbau Bodensee KOB | Streif J.,Kompetenzzentrum fur Obstbau Bodensee KOB
Acta Horticulturae | Year: 2010

1-Methycyclopropene (1-MCP; SmartFresh™) treated apples have inhibited ripening and therefore it may be possible to store treated fruit under higher than normal storage temperatures while under controlled atmosphere (CA), to provide energy and cost savings. To test this idea, a commercial case study was carried out to track the energy usage and quality changes in 'Gala' apples from two identical CA storage rooms (each 210 t) filled on the same day with fruit from the same origin and stored for 5.5 months at 1.0 kPa O 2 + 2.0 kPa CO2. One CA room was treated with 1-MCP and maintained at 4.0°C while the untreated room was kept at 1.5°C. Five grower lots, each with slightly different fruit quality characteristics were followed over the storage period with regular monitoring of fruit respiration and ethylene production. An energy balance calculated for the two rooms using the cooling equipment and CO2 absorber run time records shows 35% less energy use for the warmer temperature room. After shelf-life at room temperature fruit quality parameters from both rooms are compared, while in a sensory test (untrained panel, n=32) 1-MCP treated 'Gala' apples were slightly preferred over untreated fruit.


Neuwald D.A.,Kompetenzzentrum fur Obstbau Bodensee KOB | Streif J.,Kompetenzzentrum fur Obstbau Bodensee KOB
Acta Horticulturae | Year: 2010

Ascorbic acid (AA or vitamin C) is essential in human nutrition because of its well known health and disease prevention benefits. Apples can be a significant source of dietary vitamin C. The AA content of two important commercial apple cultivars, 'Elstar' and 'Jonagold', was followed for a few weeks directly before harvest and during a short postharvest period in regular air at two different temperatures: for up to three weeks at 20°C and for 12 weeks at 1°C. Changes in AA were also studied after the ethylene synthesis inhibitor AVG was applied pre-harvest and ethylene perception inhibitor 1-MCP was applied postharvest. AA content in untreated fruit before harvest was approximately constant, especially for 'Elstar'. However, AVG treatments applied some three or four weeks pre-harvest to apples on the tree resulted in around 10% higher AA content at harvest. Postharvest AA degradation in both cultivars was higher at 20°C than at 1°C, with 'Elstar' decreasing by some 60 to 80% and 'Jonagold' decreasing by some 30 to 60% in the three weeks following harvest. However, fruit held at 20°C plus an ethylene inhibitor treatment maintained a higher AA content: after three weeks apples treated with 1-MCP alone or with AVG plus 1-MCP showed nearly double the amount of AA compared to the untreated control or fruit treated only with pre-harvest AVG. After 12 weeks storage at 1°C, the postharvest degradation in AA was around 40% for both 'Elstar' and 'Jonagold'. The ripening inhibitors 1-MCP and AVG alone or in combination reduced AA losses under these conditions by around 10%. In general, apples treated with AVG plus 1-MCP or, to a similar extent, treated with 1-MCP alone showed the highest postharvest AA content. Higher AA concentrations in apples seem to be more a ripening retardation effect than a specific effect of either AVG or 1-MCP.


McCormick R.,Kompetenzzentrum fur Obstbau Bodensee KOB | Neuwald D.A.,Kompetenzzentrum fur Obstbau Bodensee KOB | Streif J.,Kompetenzzentrum fur Obstbau Bodensee KOB
Acta Horticulturae | Year: 2012

Storage studies undertaken in 2009-2010 with 'Elstar', 'Gala' and 'Jonagold' show 1-Methycyclopropene (1-MCP; SmartFresh™) treated apples ripen more slowly even when stored under higher than normal controlled atmosphere (CA) storage temperatures to provide energy savings, cost and environmental (reduced carbon footprint) benefits. Our studies involved three commercial storage operations in southwest Germany where comparable CA rooms were filled with pre-cooled fruit of similar origin and quality. One room was treated with SmartFresh™ and held at a temperature set-point ∼2.5°C above an untreated room. CA atmosphere conditions were different for each cultivar but identical for both untreated and treated rooms. Fruit were stored for 6 to 8 months. Energy balances calculated separately for the 'Gala' rooms from the cooling and CA equipment run time records show a 35% energy saving difference. Ripening behaviour and quality changes were monitored regularly during storage and at storage removal fruit samples were either held in ambient air for 7d or held in a simulated marketing chain followed by a short shelf-life period at ambient temperatures before quality parameters from both rooms were compared and sensory tests carried out. Results for 'Gala' apples show fruit stored at the higher temperature treated with SmartFresh™ were preferred by an untrained sensory panel. Results for 'Jonagold' and 'Elstar' were also encouraging but are not presented in detail here.

Loading Kompetenzzentrum fur Obstbau Bodensee KOB collaborators
Loading Kompetenzzentrum fur Obstbau Bodensee KOB collaborators