Edible alginate-based coating as carrier of antimicrobials to improve shelf-life and safety of fresh-cut melon.
The effect of malic acid and essential oils (EOs) of cinnamon, palmarosa and lemongrass and their main active compounds as natural antimicrobial substances incorporated into an alginate-based edible coating on the shelf-life and safety of fresh-cut "Piel de Sapo" melon (Cucumis melo L.) was investigated. Melon pieces (50 g) were coated with alginate-based edible coating containing malic acid (EC) and EOs or their active compounds before to be packed in air filled polypropylene trays and stored at 5 degrees C for shelf-life and sensory studies. On the other hand, melon pieces were inoculated with a Salmonella Enteritidis (10(8) CFU/ml) culture before applying the coatings containing malic acid and EOs or their active compounds to safety study. Controls of fresh-cut melon non-coated or coated with EC without EOs were also prepared. EC was effective to improve shelf-life of fresh-cut melon from microbiological (up to 9.6 days) and physicochemical (>14 days) points of view in comparison with non-coated fresh-cut melon, where microbiological and physicochemical shelf-life was up to 3.6 days and lower than 14 days, respectively. In addition, the incorporation of EOs or their active compounds into the edible coating prolonged the microbiological shelf-life by more than 21 days in some cases due probably to an enhanced antimicrobial effect of malic acid+EOs; however, some fresh-cut melon characteristics were affected such as firmness and color causing a reduction of physicochemical shelf-life. Significant reductions (p<0.05) of S. Enteritidis population in inoculated coated fresh-cut melon were achieved, varying the effectiveness of the coatings depending on the EOs or the active compound and their concentrations. According to the results, palmarosa oil incorporated at 0.3% into the coating appear to be a promising preservation alternative for fresh-cut melon, since it had a good acceptation by panellists, maintained the fruit quality parameters, inhibited the native flora growth and reduced S. Enteritidis population.
Raybaudi-Massilia
Rosa M
RM
Department of Food Technology, University of Lleida. UTPV-CeRTA, Av. Alcalde Rovira Roure, 191, 25198 Lleida, Spain.
Mosqueda-Melgar
Jonathan
J
Martín-Belloso
Olga
O
D000464:Alginates; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D019662:Cucurbitaceae / Q000382:microbiology*; D005506:Food Contamination / Q000032:analysis / Q000517:prevention & control; D005519:Food Preservation / Q000379:methods*; D005520:Food Preservatives / Q000494:pharmacology*; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D006801:Humans; D008293:Malates / Q000494:pharmacology; D009822:Oils, Volatile / Q000494:pharmacology*; D012477:Salmonella enteritidis / Q000187:drug effects* / Q000254:growth & development; D013997:Time Factors
D000464:Alginates; D005520:Food Preservatives; D006603:Hexuronic Acids; D008293:Malates; D009822:Oils, Volatile; C030298:malic acid; D020723:Glucuronic Acid