Antibacterial activities of R-(+)-Limonene emulsion stabilized by Ulva fasciata polysaccharide for fruit preservation.

It was previously found that R-(+)-Limonene emulsion could be stabilized by Ulva fasciata polysaccharide. In the present study, emulsions of R-(+)-Limonene were developed for coating of strawberries to improve the shelf life and microbiological safety. Edible coatings with at least 0.15% w/w of R-(+)-Limonene improved the microbial stability of the strawberries, resulted effective in the decontamination of external pathogens such as Escherichia coli, Bacillus subtilis and Staphylococcus aureus. Changes in weight loss, total soluble solid (TSS), pH, total phenolic, ascorbic acid, textural properties and surface color of strawberries during storage were evaluated. R-(+)-Limonene emulsions were effective for decreasing water loss of all the fruit samples tested. The decrease in TSS values was higher in the control strawberries. Initial decreases followed by increases of pH during storage of strawberries. The amount of total phenols detected in control fruit sharply increased during the first 6 days then remained steady, whereas the total soluble phenols content of treated strawberries gradually increased during storage. Strawberries coated with emulsion had higher L* and a* values as compared to control fruits. The R-(+)-Limonene coatings have demonstrated the potential to inhibit foodborne pathogen contamination of strawberries, and prolong their shelf life.