Abstract:
In this study, propolis was first loaded into a conventional oil-in-water emulsion, which was combined with a chitosan film-forming solution to produce propolis emulsion-loaded film (PEF). Strawberries inoculated with Botrytis cinerea coated with PEF and blank emulsion-loaded films (BEF) were stored for 14 days at 4 °C. Compared to BEF, PEF showed superior mechanical and oxygen barrier properties, as well as antioxidant activities, but higher moisture permeability. PEF showed less oil agglomeration on the film surface after drying, as demonstrated by scanning electron microscopy (SEM) analysis. Compared to uncoated strawberries, coatings did not have a significant effect on weight loss or firmness during storage. In contrast, coated strawberries showed elevated total phenolics, anthocyanins, and ascorbic acid retention; however, PEF-coating yielded higher values. Moreover, the PEF coating resulted in a significantly lower reduction of organic acid and total soluble solids. Mold growth was visible in both uncoated and BEF-coated strawberries after 7 days of storage, while PEF-coated fruits showed no visible mold until the end of storage. Starting from day 4, PEF-coated fruits showed lower mold counts (~2 log CFU/g) than other samples. Therefore, the PEF prepared in this study has application potential for the preservation of fresh fruits.
摘要:
在这项研究中,蜂胶首先被装入常规的水包油乳液中,将其与壳聚糖成膜溶液组合以产生蜂胶乳液负载膜(PEF)。将接种有涂覆有PEF的灰葡萄孢菌的草莓和空白乳液负载膜(BEF)在4°C下储存14天。与BEF相比,PEF表现出优异的机械和氧气阻隔性能,以及抗氧化活性,但透湿性较高。PEF在干燥后的薄膜表面上显示出较少的油团聚,如扫描电子显微镜(SEM)分析所示。与未涂层的草莓相比,涂层在储存过程中对重量损失或硬度没有显著影响。相比之下,有涂层的草莓显示总酚类物质升高,花青素,和抗坏血酸保留;然而,PEF涂层产生较高的值。此外,PEF涂层导致有机酸和总可溶性固体的显著较低的减少。储存7天后,在未涂覆和BEF涂覆的草莓中都可以看到霉菌的生长,而PEF涂层的水果在储存结束之前没有可见的霉菌。从第4天开始,PEF涂覆的果实显示出比其他样品更低的霉菌计数(〜2logCFU/g)。因此,本研究制备的PEF对新鲜水果的保鲜具有应用潜力。