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Israel Agriculture 2014

Figure 3. Firmness and oxygen content of the fresh cut melons coated by alginate coating, Layer-by-Layer alginate-chitosan coating, chitosan
coating and non-coated.

Layer by Layer Coatings on Fresh Agricultural Products natural ingredients and, the most important, can signifcantly
In our group we have demonstrated a practice of LbL approach improve the postharvest quality and safety of fresh
for improvement of quality and shelf-life extending of fresh agricultural products. The applications of LbL edible coating
agricultural products (Figure 1). approach on various additional fruits and vegetables are
For instance, natural polysaccharides a polyanion alginate and under investigation in our laboratory.
a polycation chitosan, were implemented on fresh-cut melon
to form LbL alginate-chitosan edible coating (Poverenov, Acknowledgement
Danino et al., 2013). These results are part of Ms. Rehyt Cohen and Mrs. Shani
The quality of melons coated by LbL coating was compared Danino fnal project thesis works in the department of Food
with quality of melons coated by single-layer alginate or Quality and Safety in Agricultural Research Organization,
chitosan coatings and with the non-coated control fruits The Volcani Center. The research leading to these results
(Figure 2 and 3). The LbL coating was found to possess was funded by the Chief Scientist of the Israeli Ministry of
benefcial properties of both ingredients, providing coated Agriculture and Rural Development and by the European
melons with good frmness, gas exchange ability and shelf Union Seventh Framework Programme (FP7/2007-2013)
life extension. under grant agreement n. 289719 (Project QUAFETY).
In additional study performed in our laboratory the References
antimicrobial efect of external antimicrobial essential oil citral Baldwin EA, Hagenmaier R, Bai J (2011). Edible Coatings and Films to
was compared with an efect of adding of second chitosan Improve Food Quality, 2nd Edition, CRC Press, Boca Raton, USA.
antimicrobial layer (Poverenov, Cohen et al., 2013). Falguera V, Quintero JP, Jimenez A, Munoz JA, Ibarz A (2011). Edible flms
It was found that the antimicrobial activity of chitosan is and coatings structures, active functions and trends in their use. Trends in
much more signifcant and can be controlled by chitosan Food Science and Technology, 22, 292-303.
Rojas-Grau MA, Soliva-Fortuny R, Martn-Belloso O (2009). Edible
concentratio. coatings
to incorporate active ingredients to fresh-cut fruits: a review. Trends in
Conclusions Food Science and Technology, 20, 438-447.
Layer by Layer edible coating approach allows combining Poverenov E, Cohen R, Yefremov T, Vinokur Y, Rodov V, (2013).
of benefcial properties of diferent coating materials. Efects of Polysaccharide-based Edible Coatings on Fresh-cut Melon
In our studies we have demonstrate the combination Quality.
of active polysaccharides with well adhesive and Acta Horticulturae. In press.
texture enhancing polysaccharides and combination of Poverenov E, Danino S, Horev B, Granit R, Vinokur Y, Rodov V (2013).
antimicrobial polysaccharide with well adhesive protein. Layer-by-Layer electrostatic deposition of edible coating on fresh cut fruit
We have successfully coated fresh cut melons utilizing LbL model: anticipated and unexpected efects of alginate-chitosan combination.
formulations based on natural edible polymers. Our coatings Food and Bioprocess Technology. In press.
Vargas M, Pastor C, Chiralt A, McClement DJ, Lez-Martinez C (2008).
have demonstrated excellent capabilities of product safety Recent Advances in Edible Coatings for Fresh and Minimally Processed
and quality improvement. The LbL method allows precise Fruits. Crit. Rev. Food Science and Nutrition. 48, 496511.
control of coating physical and mechanical properties and
the coating activity. The method is cheap, simple, based on E-mail: elenap@volcani.agri.gov.il

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