บทคัดย่องานวิจัย

The effect of methyl bromide fumigation on the skin finish of Tasmanian ‘Fuji” apples.

Brown G.S., Schimanski L.J., Schrader L., Jennings D.

5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004, p.54

2004

บทคัดย่อ

The effect of methyl bromide fumigation on the skin finish of Tasmanian ‘Fuji” apples.  Stain is a natural phenomenon o­n ‘Fuji’ apples appearing as brown patches o­n the skin of the fruit.It is often associated with areas of the fruit that have been exposed to ultra-violet radiation.Stain may occur in the weeks leading up to harvest, or during storage and transport.This discolouration id exacerbated by MeBr fumigation, as occurs for the ‘Fuji’ apples exported to Japan from Tasmania.Growers have recently become concerned that this disorder may also impact o­n domestic sales.

In the USA this disorder is considered commercially significant.This component of the project examined the post-harvest factors that impact o­n stain.During the 2002 and 2003 seasons stain increased significantlywith maturity, indicating that fruit should be picked at least 2-3 weeks earlier.It is important to note that stain varied greatly with grower-line, this could be due to microclimate effects, production practices or handling procedures.The effectiveness of post-harvest dips was examine; it was found that 2% ascorbic acid was very effective in minimising the development of stain, however this is an expensive product, so methods of application, or the use of other anti-oxidants is being explored.Grading also has a major impact o­n the development of stain.Two grading lines were examined; o­ne had high rates of stain in the picking bins but these levels increased to a maximum after the waxing process.

Fruit were placed in simulated transport at 0, 2, 4, 6 and 12 °C, it was found that the greater the simulated transport temperature the lower the incidence of stain, at the destination market due to the disappearance of the disorder.