'Annurca' apple fruit, a southern Italy apple cultivar: textural properties and aroma composition

'Annurca' apple fruit, which is commonly cultivated in southern Italy and u ndergoes a typical reddening treatment and, is notable for its high firmnes s and its characteristic flavour, was examined for its pectic and aroma com position. Pectin, extracted with a water solution of potassium oxalate and dimethylsulphoxide, was found to be quantitavely and qualitatively importan t for its contribution to the high tissue firmness. Pectin changes its comp osition during the reddening process and there is even a difference in the pectic composition of the two 'Annurca' clones examined in this paper, 'Sta ndard' and 'Rossa del Sud'. Volatile compounds were collected by headspace sampling of intact unreddened and reddened fruits. Thirty-one compounds of several chemical classes were identified, to establish their role in the ch aracteristic flavor of this apple cv. Among these compounds, M-pentanol was unusually present in large amounts; also delta -octalactone, never found i n apples, was present. (C) 2001 Elsevier Science Ltd. All rights reserved.