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Following the new eco‐friendly technologies for food packaging, biodegradable composites with edible components as starch, glycerol, and lentil flour rich in fiber (0, 0.5 wt.% and 1.0 wt.%) are developed. The lentil flour, obtained from the residue of a commercial lentil protein extraction process, have micrometer size and, unlike typical lentil flour, have three times higher concentration of fiber. Its use leads to increments in the storage modulus, strength at break, and toughness of the composites, and to decreases in water vapor permeability, with respect to the matrix, showing that the additive can act as reinforcement for starch films. Composites with 0.5 wt.% of flour result in more flexibility due to their homogeneous dispersion in the matrix. All films are thermally stable up to 240 °C and biodegradable in vegetal compost after 4 weeks. These new composites are high promising for use as biodegradable and edible food coatings. They could enrich food nutritional value by the fiber‐rich flour addition.

Andean blueberry is a promissory fruit native to South America. The current work aimed to characterize starches isolated from Colombian native potatoes and to evaluate the effect of the application of starch edible coatings on the changes in the physicochemical quality parameters of the Andean blueberry during storage. Starches were isolated from three different potatoes varieties (pacha negra, mora, and alcarrosa) and characterized. Then, starch-based coatings were applied to Andean blueberries, and the changes in their quality parameters were monitored during 12 days of storage. Despite the phenotypical differences in the starch sources used, starches were similar in terms of their granule morphology, amylose content (~19%), crystallinity degree (~46%), and thermal properties. Coatings were able to reduce the gaseous exchange of the fruit, and, thus, the respiration rate of all coated blueberries was ~27% lower compared to the uncoated fruits (p < 0.05) at the end of the storage. While the application of starch coatings did not prevent water loss, all samples reached water loss of up 20%. Besides, the coated fruits showed soluble solids contents ~14% higher compared to the control one, as well as better bright and firmness. The new edible coatings can help add value to the Andean blueberry.

Edible coatings and films are appealing strategies for the postharvest management of blueberries. In the current work, alginate and alginate/cellulose nanofibril (CNF) edible coatings crosslinked with calcium chloride were developed for application on Andean blueberry (a promissory wild blueberry). Cocoa by-products were valorized through the isolation of their CNFs, and these were incorporated in the edible coatings. Edible coating formulations were based on blends of alginate (2% w/v), CNFs (0%, 0.1%, or 0.3%), glycerol, and water. In addition, stand-alone films were prepared, and their light and water vapor barrier properties were studied before applying the coating on the fruit surface. The results show that the addition of CNFs caused a significant decrease in the transparency and the water vapor permeability of the alginate films. After applying on the Andean blueberry fruits, the alginate and alginate/CNF coatings enhanced the appearance and the firmness of the fruits. Moreover, they significantly reduced the respiration rate and the water loss of the Andean blueberries throughout the 21 days of refrigerated storage. Alginate and alginate/CNFs coatings may be considered a useful alternative for the delay of the postharvest deterioration of Andean blueberries.

Edible coatings are attractive strategies for blueberries postharvest preservation. In this work, carvacrol/alginate coatings were developed for application on Andean blueberries. Coating formulations were prepared based on blends of sodium alginate (2% w/v), carvacrol (0%, 0.03%, 0.06% or 0.09%), glycerol, and water and applied to the fruits by dip-coating. Then, the fruits were immersed in a calcium batch to induce a crosslink reaction. Changes in the physicochemical and microbiological characteristics of the blueberries were monitored during 21 days of storage at 4 °C. Coated blueberries were better preserved throughout the 21 days of storage because of their lower respiration rate and water loss, in comparison with the uncoated ones. Besides, the coatings enhanced the appearance and the gloss of the fruits. Control fruits showed a significant decrease in the firmness, while, in the coated fruits, this critical postharvest quality was preserved during the entire storage. Coating formulations with 0.09% of carvacrol was the most effective in preventing mesophilic aerobic bacteria and molds/yeasts growth on the fruits during the storage. Edible carvacrol/alginate coatings can be considered as a useful alternative to complement the benefits of refrigerated storage by delaying post-harvest spoilage of Andean blueberries.

Natural extracts are investigated as plasticizers of starch–glycerol biobased films for food coating applications. For this purpose, films with cassava starch, glycerol, and distilled water with and without green tea or basil extracts are obtained by solvent casting. The plasticizing effect of the extracts is confirmed from the films crystalline structure, thermal degradation behavior, glass transition temperature, and tensile properties. Increased mobility of starch chains is the result of a strong interaction between extract components and starch molecules. The Kohlrausch–Williams–Watts (KWW) theoretical modeling, used for the first time to determine the effect of antioxidant components in starch films, also confirms the plasticizing effect of either green tea or basil extracts. In addition, the original luminosity of the starch film is not compromised by the incorporation of the extracts. Moreover, a delay in the starch retrogradation is achieved, making the film more durable and hence, very promising to be used as food coating.