Next Article in Journal
Microbial Ecology of Greek Wheat Sourdoughs, Identified by a Culture-Dependent and a Culture-Independent Approach
Previous Article in Journal
Synthesis, Characterization, and Evaluation of Genistein-Loaded Zein/Carboxymethyl Chitosan Nanoparticles with Improved Water Dispersibility, Enhanced Antioxidant Activity, and Controlled Release Property
Article

Edible Coatings Containing Oregano Essential Oil Nanoemulsion for Improving Postharvest Quality and Shelf Life of Tomatoes

1
Department of Industrial Engineering, University of Salerno, via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
2
ProdAl Scarl, via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
*
Author to whom correspondence should be addressed.
Foods 2020, 9(11), 1605; https://doi.org/10.3390/foods9111605
Received: 8 October 2020 / Revised: 29 October 2020 / Accepted: 2 November 2020 / Published: 4 November 2020
(This article belongs to the Section Food Packaging and Preservation)
Edible coatings have attracted significant interest in maintaining quality and improving the shelf life of fresh fruit and vegetables. This study aimed to improve tomato storability by using edible coatings, based on alginate cross-linked with calcium chloride, and containing an oregano essential oil (OEO) nanoemulsion as a natural antimicrobial. The coating formulations were preliminary optimized in terms of alginate and calcium chloride concentrations, using response surface methodology, to obtain a thin (~5 µm) and uniform layer on the tomatoes surface. The optimized coating (prepared using sequential dipping in a 0.5% w/w sodium alginate solution and in a 2.0% w/w calcium chloride solution) was enriched by incorporating an OEO nanoemulsion, formulated with lecithin as a natural emulsifier, at an OEO concentration of 0.17% w/w in the alginate solution. The nanoemulsion did not significantly affect the coating thickness and uniformity but improved the wettability of the tomato skin. More specifically, the alginate-based edible coatings exhibited a strong interaction with the hydrophobic tomato skin surface (higher than water), promoting surface adhesion. The addition of OEO nanoemulsion in the coating, by providing more hydrophobic sites, further improved the wetting capability and adhesion of the coating solution on the tomato surface. The developed edible coatings successfully contributed to prolonging the tomato shelf life, by reducing the growth of the endogenous microbial flora (total microbial load, yeasts, and molds) over 14 days at room temperature in comparison with the control, with significantly better performances for the edible coating containing the OEO nanoemulsion. View Full-Text
Keywords: sodium alginate; calcium chloride; oregano essential oil; antimicrobial agent; response surface methodology; preservation; storability sodium alginate; calcium chloride; oregano essential oil; antimicrobial agent; response surface methodology; preservation; storability
Show Figures

Graphical abstract

MDPI and ACS Style

Pirozzi, A.; Del Grosso, V.; Ferrari, G.; Donsì, F. Edible Coatings Containing Oregano Essential Oil Nanoemulsion for Improving Postharvest Quality and Shelf Life of Tomatoes. Foods 2020, 9, 1605. https://doi.org/10.3390/foods9111605

AMA Style

Pirozzi A, Del Grosso V, Ferrari G, Donsì F. Edible Coatings Containing Oregano Essential Oil Nanoemulsion for Improving Postharvest Quality and Shelf Life of Tomatoes. Foods. 2020; 9(11):1605. https://doi.org/10.3390/foods9111605

Chicago/Turabian Style

Pirozzi, Annachiara, Vittoria Del Grosso, Giovanna Ferrari, and Francesco Donsì. 2020. "Edible Coatings Containing Oregano Essential Oil Nanoemulsion for Improving Postharvest Quality and Shelf Life of Tomatoes" Foods 9, no. 11: 1605. https://doi.org/10.3390/foods9111605

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop