Armando Testoni

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

‘Annurca’ apple fruit, which is commonly cultivated in southern Italy and undergoes a typical reddening treatment and, is notable for its high firmness and its characteristic flavour, was examined for its pectic and aroma composition. Pectin, extracted with a water solution of potassium oxalate and dimethylsulphoxide, was found to be quantitavely and qualitatively important for its contribution to the high tissue firmness. Pectin changes its composition during the reddening process and there is even a difference in the pectic composition of the two ‘Annurca’ clones examined in this paper, ‘Standard’ 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 characteristic flavor of this apple cv. Among these compounds, n-pentanol was unusually present in large amounts; also δ-octalactone, never found in apples, was present.

Ethylene Development in Different Clones of ‘Annurca’ Apple and Its Influence on the Biosynthesis of Aroma Esters and Alcohols

‘Annurca’ (Malus domestica Borkh) is an apple cv commonly cultivated in Southern Italy. Its aroma composition is characteristic and completely different from other apple’s cv. The I.S.F. (Experimental Institute of Fruit Growing) in Rome, Italy, has selected several clones of this cv, in order to attenuate the agronomical ‘Annurca’ defects. We studied the headspace composition (ethylene, esters and alcohols) of intact, unreddened fruits just after harvest and after storage in air or in controlled atmosphere. Relationships between ethylene amount in the headspace and esters or alcohols production were evaluated in order to determine the optimum of storability for every clone and the best aroma retention.