The effect of environmental conditions on nutritional quality of cherry tomato fruits: evaluation of two experimental Mediterranean greenhouses.

BACKGROUND The aim of this study was to examine how different environmental factors (temperature, solar radiation, and vapour-pressure deficit [VPD]) influenced nutritional quality and flavour of cherry tomato fruits (Solanum lycopersicum L. cv. Naomi) grown in two types of experimental Mediterranean greenhouses: parral (low technology) and multispan (high technology). RESULTS Fruits were sampled three times during 3 years (2004, 2005 and 2006): at the beginning, middle and end of the fruit production period. Values for temperature, solar radiation, and VPD peaked in the third sampling in both greenhouses; values were higher in the parral-type greenhouse, triggering abiotic stress. This stress reduced the accumulation of lycopene and essential elements, augmenting the phytonutrient content and the antioxidant capacity of tomatoes. During the third sampling, sugars were increased while organic acid content diminished, producing tomatoes with a sweeter-milder flavour. The parral greenhouse produced tomatoes with higher phenolic compounds and ascorbic acid contents, together with a greater antioxidant capacity, without showing differences in flavour parameters. CONCLUSION The higher phytonutrients content and antioxidant activity during the environmental stress, more pronounced in parral than multispan greenhouse, together with the sweeter-milder flavour, conferred a notable nutritional benefit, which considerably improved the nutritional and organoleptic quality of these tomatoes.