Modifications in biosynthesis of aroma volatile compounds in ‘Fuji’ apples after controlled-atmosphere storage.
Lara I., Jove J., Graell J., Lopez M.L., Echeverria G.
5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004, p.70
2004
บทคัดย่อ
Modifications in biosynthesis of aroma volatile compounds in ‘Fuji’ apples after controlled-atmosphere storage.
Although controlled-atmosphere (CA) storage is a common practice allowing longer commercial availability of a number of fruits, such storage conditions have been reported to decrease volatile production in some apple (Malus domestica Borkh.) cultivars, and thus to be detrimental to fruit aroma.Because “Fuji” is a cultivar showing excellent organoleptic quality and long-term storage potential, it is desirable to optimise conditions for maintaining fruit quality throughout storage.“Fuji” apples were harvested at commercial maturity in an orchard near Lleida (Spain).Immediately after harvest, fruit were selected for uniformity, and cold-stored under air (21 kPa O2 + 0.03 kPa CO2) or under three different CA conditions (3 kPa O2 + 2kPa CO2; 1kPa O2 + 1 kPa CO2; or 1 kPa O2 + 2kPa CO2) during a period of 3, 5, or 7 months, after which apples were placed at 20 °C.Emission of aroma volatile compounds, acetaldehyde and ethanol contents, and some enzyme activities related to volatile biosynthesis were assessed 4 days thereafter, and used for Principal Component Analysis (PCA) of results.Storage caused modifications in the aroma profile as compared to the moment of fruit harvest: ethyl hexanoate, on of the main compound contributing to aroma of freshly-harvested fruit, was undetectable after storage, regardless of conditions.PCA revealed differences according to storage atmosphere and storage period, the main volatile compounds contributing to “Fuji” aroma profile being associated to cold storage in air and correlated to higher pyruvate decarboxylase activity and acetaldehyde content.Storage under ultra-low oxygen concentrations was associated to increased alcohol dehydrogenase activity and ethanol contents.The highest emission of total volatile compounds after storage was found to be closely related to differences arising from storage period.