title: Influence of hydroponic and soil cultivation on quality and shelf life of ready-to-eat lamb's lettuce (Valerianella locusta L. Laterr).
abstract: BACKGROUND
  Nowadays, there is an increasing interest in the hydroponic floating system to cultivate leafy vegetables for ready-to-eat salads. It is reasonable that different growing systems could affect the quality and shelf life of these salads.
  
  
  RESULTS
  The quality and shelf life of ready-to-eat lamb's lettuce grown in protected environment in soil plot or in soil-less system over hydroponic solution with or without the addition of 30 µmol L⁻¹ silicon were evaluated. Minimum effects were observed on colour, firmness and microbial counts. Hydroponic cultivation largely affected plant tissue hydration, leading to weight loss and structural modifications during refrigerated storage. The shelf life of lamb's lettuce was limited by the development of visually detectable unpleasant sensory properties. Shelf life, calculated by survival analysis of consumer acceptability data, resulted about 7 days for soil-cultivated salad and 2 days for the hydroponically grown ones. The addition of silicon to the hydroponic solution resulted in an interesting strategy to increase plant tissue yield and reduce nitrate accumulation.
  
  
  CONCLUSIONS
  Although hydroponic cultivation may have critical consequences on product quality and shelf life, these disadvantages could be largely counterbalance by increased yield and a reduction of nitrate accumulation when cultivation is performed on nutritive solutions with supplemental addition of silicon.
authors.affiliation: Dipartimento di Scienze degli Alimenti, University of Udine, Via Sondrio 2, I-33100 Udine, Italy. lara.manzocco@uniud.it
authors.forename: Lara
authors.initials: L
authors.lastname: Manzocco
authors.forename: Martina
authors.initials: M
authors.lastname: Foschia
authors.forename: Nicola
authors.initials: N
authors.lastname: Tomasi
authors.forename: Michela
authors.initials: M
authors.lastname: Maifreni
authors.forename: Luisa
authors.initials: L
authors.lastname: Dalla Costa
authors.forename: Marilena
authors.initials: M
authors.lastname: Marino
authors.forename: Giovanni
authors.initials: G
authors.lastname: Cortella
authors.forename: Stefano
authors.initials: S
authors.lastname: Cesco
mesh_terms: D000293:Adolescent; D000328:Adult; D018533:Biomass; D003116:Color; D003258:Consumer Behavior; D057140:Fast Foods; D005260:Female; D005511:Food Handling / Q000379:methods; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods*; D006801:Humans; D018527:Hydroponics / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000378:metabolism; D018515:Plant Leaves / Q000254:growth & development / Q000382:microbiology; D012034:Refrigeration; D012825:Silicon / Q000378:metabolism; D012987:Soil; D032406:Valerianella / Q000254:growth & development*; D014675:Vegetables / Q000254:growth & development* / Q000382:microbiology / Q000592:standards; D014867:Water / Q000378:metabolism; D055815:Young Adult
chemical_list: D009566:Nitrates; D012987:Soil; D014867:Water; D012825:Silicon