Extension of Blueberry Shelf-Life with Edible Coatings from Chlorella Vulgaris

Abstract

Berries are fruits with a particularly high nutritional value and content of bioactive components, which leads to an ever-increasing demand. However, their supply is hampered by their seasonality and sensitivity while being transported and stored. Typically, oxidative reactions, contamination by pathogenic microorganisms, bacteria that induce spoiling, respiratory processes, and poor storage conditions lead to degradation. In the food sector, it is still very difficult to extend the shelf life of berries while retaining their nutritional composition, physical properties, and appealing appearance. Edible coating is an emerging food protection procedure, as it can increase the shelf life of berries, is a sustainable process, and can be safely consumed as part of the product. The aim of this study is to investigate the effect of edible coatings developed components derived from microalgae (Chlorella vulgaris) on the shelf life of blueberries and compare them with conventional ones. Polysaccharides and proteins were extracted from Chlorella vulgaris and were incorporated into a membrane system that also contained plasticizers and other elements The creation of conventional membranes involved the use of chitosan and potato starch. The created coatings were applied to the berries, which were then analysed for colour, weight loss, content of Total Soluble Solids, Total Acidity, Antioxidant Activity and microbiological growth in order to establish the shelf-life of the product. The coatings made from algae extracts, according to the results of all tests, produced products with excellent quality and long shelf lives.