Effect of Alginate and Chitosan Edible Coating Enriched with Olive Leaves Extract on the Shelf Life of Sweet Cherries (Prunus avium L.)

Wissam Zam

doi:10.1155/2019/8192964

Abstract

Edible film coatings are widely used as a protective barrier for the reduction of transpiration and respiration, therefore reducing the ripening process in fruits and vegetables and improving their quality. The influence of chitosan 1% and alginate 3% enriched with olive leaves extract (OLE) on the quality of sweet cherries was studied. Overall, the ripening process and the increase in anthocyanins were found to be delayed with the use of coating particularly those composed of chitosan in combination with OLE. Ascorbic acid and total phenolic contents were recorded with restricted loss at the end of 20 days of storage in both chitosan- and alginate-coated samples enriched with OLE. Higher values of antioxidant activity expressed as the percentage inhibition of DPPH were reported in correlation with phytochemical content. It could be concluded that chitosan and alginate coating enriched with OLE could be efficient for prolonging the shelf life of sweet cherries.

Highlights

Sweet cherry (Prunus avium L.) is one of the most appreciated fruits by consumer due to its high content in essential dietary components and is mainly consumed as not processed
Weight loss increased during storage, reaching values of 9.63 ± 0.12% in control fruit after 20 days. e weight loss was significantly lower at 8.83 ± 0.21%, 7.75 ± 0.08%, 6.13 ± 0.26%, and 5.35 ± 0.17% in samples coated with alginate, alginate + olive leaves extract (OLE), chitosan, and chitosan + OLE, respectively. is weight loss is correlated with an increase in water loss due to rise in transpiration and respiration [19]
Similar results were reported in previous studies with other edible coatings and concluded that edible films created a physical barrier against moisture loss and reduced the transpiration rate [29]

Summary

Introduction

Sweet cherry (Prunus avium L.) is one of the most appreciated fruits by consumer due to its high content in essential dietary components and is mainly consumed as not processed. The preservation of fruit quality and the increase of their shelf life are maintained by the use of edible coatings which could retard some physiological processes such as respiration and transpiration [3]. Chitosan is a high-molecular-weight carbohydrate polymer produced by the deacetylation of chitin [5]. It is widely applied in the storage of fruits and vegetables as a semipermeable lm that regulates the internal atmosphere and reduces the transpiration, extending their shelf life [5]. Results of di erent studies proved that the application of chitosan was e ective in retarding the ripening process of strawberries [6], sweet cherries [7], papaya [3], and carambola [8]

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