Sensory properties of canned cardoon hearts in relation to genotype

Wild cardoon (Cynara cardunculus L var. sylvestris (Lam.) is widespread in Sicily by several populations and immature inflorescences are usually collected and cooked during spring utilizing them as traditional starters or for home processing use. Sometimes, the capitula heads are sold in local market, both raw or already boiled in traditional big containers. Considering the high nutraceutical value of this product, similar to globe artichoke, and the lack of research activities related to this product of Sicilian tradition, the aim of this work, was to individuate the variation of the firmness and of browning indices in relation to the heating/cooking time/treatment and to the different accessions collected in Sicily and conserved ex situ at CNR ISAFOM. Four accessions of cardoon, one belonging to var. altilis and three to var. sylvestris collected at Syracuse (SR, Italy), S. Domenica Vittoria (ME, Italy) and Polverello (ME, Italy), before flowering stage were object of our attention. The harvested capitula were subjected to a dipping of the hearts at 0°C in a water solution of sodium hypochlorite 0.5% (v/v) for 30 min. In order to assess the optimal firmness along the time, a heating treatment from 2 min intervals until 28 min was performed, using distilled water in a ratio of 1 g capitula:10 mL water. On raw hearths and every four two minutes for a total of seven samplings; on 6 hearths (experimental unit), the weight (g), the colour of the external bracts (Minolta CR-400) and the firmness (kg cm-2) were determined. The firmness was acceptable until 8 min, after this time the softness determined the damage of the tissues, especially in genotypes with the lowest bud size. The lightness L* decreased from 52 (0 min) to 42 (28 min) and the C* increased, passing from 11.1 (0 min) to 18.1 (28 min). This paper gives useful information about the cooking process of cardoon to obtain new stored nutraceutical products.