Peña-Ortiz Manuel, Serrano Luis, Romero Antonio A, García Araceli
FQM-383 NANOVAL Group, Organic Chemistry Department, University of Córdoba, Campus de Rabanales, Marie Curie Building, Ctra. Nnal. IV-A, Km 396, 14014 Córdoba, Spain.
BioPrEn Group (RNM 940), Chemical Engineering Department, Instituto Químico para la Energía y el Medioambiente (IQUEMA), Faculty of Science, University of Córdoba, 14014 Córdoba, Spain.
Foods. 2023 Oct 11;12(20):3741. doi: 10.3390/foods12203741.
Ethanolic extracts of bay leaves were obtained using the Soxhlet method (extraction yield of 22.3 ± 1.2%) and further analyzed through different methods, thus determining the chemical composition with gas chromatography, phenolic content with the Folin-Ciocalteu technique (11.8 ± 0.4% wt.) and antioxidant power with the radical 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) method (75.06%). Furthermore, its effect on the growth of two bacteria, and , and on two yeasts, and , was determined, showing a minimum inhibitory concentration of 0.65 mg/mL on the growth of . Finally, edible films were prepared using different polymers (carboxymethyl cellulose, gum Arabic, polyvinyl pyrrolidone, and polyvinyl alcohol) containing 0, 5, 10, or 15% wt. of bay leaf extract as troubleshooting for perishable fruits, specifically for cultivated strawberry. The prepared composites presented reduced water vapor permeabilities (up to 4.3 × 10 g·Pa·m·h), high specific transparencies (≈30%/mm), as well as the effective blocking of ultraviolet radiation (>99.9%). In vivo tests showed that the most suitable treatment for strawberry protection was the impregnation with a composite comprising polyvinyl alcohol and a 15% wt. bay leaf extract, resulting in a noteworthy reduction in mass loss (22% after 6 days). It can be asserted that food packaging with the designed composites would be an effective alternative for the reduction in postharvest losses.
采用索氏提取法获得月桂叶乙醇提取物（提取率为22.3±1.2%），并通过不同方法进一步分析，从而用气相色谱法测定其化学成分，用福林-西奥尔特法测定酚含量（11.8±0.4%重量），用2,2'-联氮-双（3-乙基苯并噻唑啉-6-磺酸）自由基法测定抗氧化能力（75.06%）。此外，还测定了其对两种细菌（ 和 ）以及两种酵母（ 和 ）生长的影响，结果表明对 的生长最低抑菌浓度为0.65mg/mL。最后，使用含有0、5、10或15%重量月桂叶提取物的不同聚合物（羧甲基纤维素、阿拉伯胶、聚乙烯吡咯烷酮和聚乙烯醇）制备可食用薄膜，作为易腐水果（特别是栽培草莓）的保鲜措施。制备的复合材料具有降低的水蒸气透过率（高达4.3×10 g·Pa·m·h）、高比透明度（≈30%/mm）以及对紫外线辐射的有效阻隔（>99.9%）。体内试验表明，对草莓保鲜最合适的处理方法是用含有聚乙烯醇和15%重量月桂叶提取物的复合材料浸渍，可使质量损失显著降低（6天后为22%）。可以断言，用设计的复合材料进行食品包装将是减少采后损失的有效替代方法。
