Characterization of Starches Isolated from Colombian Native Potatoes and Their Application as Novel Edible Coatings for Wild Andean Blueberries (Vaccinium meridionale Swartz)

Abstract

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.

Improvement of Andean Blueberries Postharvest Preservation Using Carvacrol/Alginate-Edible Coatings

“…Uncoated fruits showed lower lightness (L*) (i.e., a darker color) than coated ones; while not statically significant differences were found between the lightness obtained for the fruits coated with alginate and alginate-carvacrol (alginate/CVR 0.03%; alginate/CVR 0.06% and alginate/CVR 0.09%) during the storage ( Figure 3 A). This appearance improvement could be due to that the smoother surface of the coated fruits caused a greater visible light reflection [ 6 , 36 ]. Similar behaviors have been reported in strawberries coated with chitosan-oleic acid [ 36 ] and with alginate-carvacrol [ 20 ].…”

“…However, it has been stated that consumers prefer unwaxed foods because some do not know why wax is used and link this material with health and environmental concerns [ 5 ]. Therefore, several investigations have been made to develop new edible coatings based on odorless, tasteless, and colorless natural polymers such as starch, chitosan, pectin, guar gum, and alginate, which do not exhibit adverse effects on the food sensory quality [ 6 ].…”

“…Therefore, there is a need to overcome these difficulties through the application of safe and environmentally friendly postharvest technologies for its preservation such as edible coatings. In our previous study, the effect of coatings based on starches and alginate/nanocellulose blends on the postharvest preservation of Andean blueberries was reported for the first time [ 6 , 25 ]. It was found that alginate coatings exhibited better performance on the weight loss reduction and the fruit firmness, in comparison with starch ones.…”

Edible and Functionalized Films/Coatings—Performances and Perspectives

“…Andean blueberries [93] were protected using starch-glycerol films, the starch source being Colombian native potatoes: pacha negra, mora, and alcarrosa. For all three types of starch, the reduction in gas exchange was found to be approximately 27%.…”

Alginate-Edible Coatings for Application on Wild Andean Blueberries (Vaccinium meridionale Swartz): Effect of the Addition of Nanofibrils Isolated from Cocoa By-Products

“…It can be seen that the coated fruits were brighter than the uncoated ones. This behavior was attributed to the smoother surface of the coated fruit, compared to the fruit skin, and it caused a greater reflection of visible light [35]. The brightness is an important quality perceived attributed to blueberries because consumers commonly associate it with a fresh-like appearance [36].…”