Sensory analysis, sugar and acid content of tomato at different EC values of the nutrient solution

The influence of three concentrations of nutrient solution (electrical cond uctivity, EC: 1.0, 3.5 and 6.0 dS m(-1)) on the sensory properties of tomat o was investigated. Two tomato cultivars representing two types-a conventio nal round tomato (cv. Counter) and a round longlife tomato (cv. Vanessa)-we re harvested from a closed hydroponic system with recirculating nutrient so lution. The same products were investigated by quantitative descriptive ana lysis with trained panellists and by an acceptance test with consumers. Fur thermore, the contents of reducing sugars and the titratable acid of fruits were analysed. To find explanations for consumer preferences relationships between the results of quantitative descriptive analysis, consumer accepta nce tests and the sugar and acid contents of the fruits were investigated. The quantitative descriptive analysis revealed changing intensities of sens ory attributes of appearance, firmness by touch, flavour, aftertaste and mo uthfeel with increasing nutrient solution EC. However, the change of differ ent sensory attributes was different for the two cultivars. Intensity of un favourable flavour attributes such as mouldy, spoiled sweetish and hitter w as stronger only for the longlife cultivar when cultivated at high EC. High er EC values resulted in higher contents of reducing sugars and titratable acid, which influenced the intensity of several sensory attributes of smell , flavour and aftertaste evaluated by the descriptive panel.