TOMATO QUALITY EVALUATION BY DIFFERENT CULTIVATION TECHNIQUES: CONVENTIONAL vs HYDROPONIC METHOD.

In the recent years, the hydroponic method (also called soilless) have spread from the greenhouse cultivations. The hydroponic methods use several substrates like the stone wool or coconut fibers for substitute the soil. In Italy 1.800 hectares of hydroponic cultivations that represent the 5% of all greenhouse cultivation. The tomatoes cultivation is one of principal Italian ones, and recently also the hydroponic tomatoes cultivation is growing up, especially in the Sicilia and Sardegna regions. For this reason, in the present period a great amount of table tomatoes come from hydroponic cultivations, and this quantity is probably growing. Italy imports a significant amount of tomatoes, around the 10% of tomatoes consumed come from other countries and almost half of imported tomatoes come from Netherland. The Netherland case is important because the 90 % of greenhouse cultivations is given by the hydroponic one [1]. The tomatoes varieties cultivated in the producer countries are constituted of selected “F1” hybrids [2],these species are chosen for their productivity, resistance to storms and their quality (uniformity and shelf-life). Recent studies shown like fruit and vegetables cultivated with soilless methods had higher nutritional values compared to the same cultivars obtained by conventional techniques. Some studies (deal with grapes and lettuce) demonstrate that cultivation by soilless system shows an increase of antioxidant capacity and total phenolic compounds of the products, with a higher resistance of the organoleptic and shelf-life parameters [3-4]. Also studies on tomato highlight like through the nutrient control and growing conditions of soilless plants could be increased the antioxidant amount in the final product. This happens in conditions of nutrients with high salinity degree, that lead at a minor harvest of yield but at a higher production of bioactive substances and secondary metabolites. These compounds could be represented a valuable investment in regions with low quality of water [5-6]. The aim of the present work is to evaluate the quality parameters and the potential differences in nutraceutical compounds from tomatoes coming from conventional cultivation and from the hydroponic one. The parameters selected, like best representative for their properties, was vitamin C, total phenolic compounds, antioxidant capacity, organic acids and biogenic amines. The chemical analysis method involved are spectrophotometric and chromatographic, in addition to economic analysis like LCA.