|MARIN, ANNA - Universidad De Valencia|
|ATARES, LORENA - Universidad De Valencia|
|CHIRALT, AMPARO - Universidad De Valencia|
Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/19/2018
Publication Date: 2/1/2019
Citation: Marin, A., Plotto, A., Atares, L., Chiralt, A. 2019. Lactic acid bacteria incorporated into edible coatings to control fungal growth and maintain postharvest quality of grapes. HortScience. 54:337-343. https://doi.org/10.21273/HORTSCI13661-18.
Interpretive Summary: Edible coatings based on a polysaccharide (starch) or protein (casein) were formulated with or without Lactobacillus plantarum to study their effect as postharvest decay control on table grape. Casein-based coatings were better than starch-based coatings at maintaining Lactobacillus populations on the fruit surface. On the other hand, starch-based coatings with Lactobacillus were more effective at reducing Botrytis decay on fruit after 7 days storage. Neither coating had much effect on fruit quality. This study provides a base to develop an alternative strategy to apply biocontrol agents on fresh fruit to control postharvest decay.
Technical Abstract: Lactic acid bacteria (LAB) have been shown to prevent the growth and activity of several postharvest pathogen fungi in fruit and vegetables, because of their ability to produce antimicrobial metabolites. Edible coatings (EC) can be used as carriers of LAB and could provide an alternative natural preservation method. The effectiveness of Lactobacillus plantarum against fungal decay on grapes applied together with EC was studied. Different formulations containing or not L. plantarum were considered, using pre-gelatinized potato starch (PS) or sodium caseinate (NaC) as main components of the coating matrices. In some of the formulations, oleic acid (OA) was added as a surfactant. The population dynamics of the bacterium and its ability to control fungal decay were studied together with the assessment of fruit quality. NaC based formulations improved survival of L. plantarum on fruit surface after 7 days of storage in comparison with water control. On the other hand, L. plantarum in PS based formulation without OA reduced Botrytis incidence more than when applied in NaC formulation or in water. Coatings had little effect on berry quality (weight, color, firmness, and soluble solids content) of grapes throughout storage, although some of the coated samples maintained acidity and maturity index during storage better than others. Therefore LAB applied in EC could provide a viable biocontrol method for postharvest disease in grape.