Skip to main content
Optimisation of Steamer Jet-Injection to Extend the Shelf Life of Fresh-Cut Lettuce
  • Daniel Rico, Dublin Institute of Technology
  • Ana Belen Martin-Diana, Dublin Institute of Technology
  • Catherine Barry-Ryan, Dublin Institute of Technology
  • Gary Henehan, Dublin Institute of Technology
  • J. Barat, Universidad Politicnica Camino de Vera
  • Jesus Maria Frias, Dublin Institute of Technology
Document Type
Publication Date
This item is available under a Creative Commons License for non-commercial use only
Publication Details

Postharvest Biology and Technology, vol.48, 2008, p.431-442

Available from the publisher here

Optimisation of short time blanching (steaming) was investigated using response surface methodology by analysing quality and microbial and nutritional markers over the shelflife of packaged fresh-cut lettuce. Steamer treatment time (5–10 s) and storage (1–10 days) were used as independent factors in order to optimise the process. Longer treatments (>10 s) were not feasible because of extensive damage caused to lettuce tissue. Significantly (p < 0.05) higher values of luminosity (L*), greenness (−a*) and sensory panel scores (fresh appearance, general acceptability and absence of browning) were obtained with samples treated for longer times with the steamer. Activity of browning-related enzymes present in photosynthetic tissue decreased in all the cases, however, longer treatment time (7.5–10 s) was needed with vascular tissues to reduce to similar activity values. These differences could be explained by the variation in tissue thickness. The longest steam treatment (10 s) reduced and maintained significantly (p < 0.05) lower mesophilic load than shorter treatments (5–8.5 s). However, significant (p < 0.05) decreases in vitamin C and carotenoids were observed in samples treated with longer treatments. Steamer treatment of 10 s could be considered the optimum time for maintaining the shelflife (mainly texture and browning) of fresh-cut lettuce for 7–10 days in optimum conditions.
Citation Information
Rico, D., Martin-Diana, A., Barry-Ryan, C., Henehan, G., Barat, J., Frias, J.: Optimisation of steamer jet-injection to extend the shelf life of fresh-cut lettuce. Postharvest Biology and Technology, Volume 48, Issue 3, June 2008, Pages 431-442. doi:/10.1016/j.postharvbio.2007.09.013