Chemical and sensory analysis of commercial tomato juices present on the Italian and Spanish markets.

A quantitative descriptive analysis was developed to characterize the sensory quality of a set of 12 organic and conventional tomato juices sold in Spanish and Italian markets. The volatile compounds of tomato juices were also studied. Twelve sensory descriptors, selected by a trained panel, evaluated the sensory profile of the samples. Some tomato juices were characterized by dominant positive notes typical of tomatoes (tomato paste, vegetable notes), whereas others by negative sensory attributes (off-flavors, high intensity of acidity, and sweetness). The volatile pattern of the samples, studied by SPME/GC-MS, was correlated with the sensory results: basically, organic tomato juices were characterized by vegetable notes and higher volatile compounds than conventional samples, regardless of their geographical origin. Conventional tomato juices were grouped in a closer cluster, whereas organic tomato juices were more diversified. Moreover, "defective" samples showed higher amounts of 3-methyl-1-butanol.