植物精油强化海藻酸钠-明胶可食性复合膜的制备及其抑菌性能研究

Preparation and antibacterial properties of plant essential oil-enhanced sodium alginate-gelatin edible composite films

中文关键词:  可食性复合膜  明胶  海藻酸钠  植物精油  抑菌性  食品保鲜

英文关键词:edible composite films  gelatin  sodium alginate  plant essential oils  antibacterial properties  food preservation

中文摘要:

      目的 开发一种基于海藻酸钠和明胶基质、并强化多种植物精油(异硫氰酸苄酯、丁香酚、香芹酚、肉桂醛、姜黄精油)的新型可食性复合膜, 考察其抑菌性能, 并评估其在常温牛肉保鲜中的应用潜力。方法 本研究以海藻酸钠和明胶为成膜基材, 添加上述植物精油, 分别采用共混搅拌和乳化均质两种工艺制备植物精油-海藻酸钠-明胶可食性复合膜。通过对复合膜的表观形态进行观察, 并系统测定其精油负载率、释放率及抑菌性等关键指标, 综合评价两种制备方法对复合膜性能的影响。结果 乳化均质工艺相较于共混搅拌工艺, 能显著提升植物精油在复合膜中的负载率, 并实现更缓慢的精油释放。乳化均质法制备的复合膜中, 精油分散更均匀, 结构更致密。乳化均质法制备的复合膜对金黄色葡萄球菌和沙门氏菌表现出更强的抑菌活性, 抑菌圈更大, 菌落总数显著降低。使用植物精油复合膜包裹的牛肉, 在常温(25 ℃)下贮藏60 h后, 感官评分仍处于可接受范围。所有复合膜在28 d内生物降解率均达82.83%~90.55%, 具备良好环境友好性。结论 乳化均质工艺能有效优化植物精油在海藻酸钠-明胶复合膜基质中的分散状态, 促进精油的缓释行为, 从而显著提升复合膜的抑菌效能。该研究为开发高性能可食性抗菌包装材料提供了重要依据, 所制备的植物精油强化复合膜在延长食品货架期、提升食品安全性方面, 展现出良好的应用前景。

英文摘要:

      Objective To develop a new edible composite film based on sodium alginate and gelatin matrix and fortified with multiple plant essential oils (benzyl isothiocyanate, genol, carvacrol, cinnamaldehyde, turmeric essential oil), investigate its antibacterial performance, and evaluate its application potential in the preservation of beef at room temperature. Methods Sodium alginate and gelatin were utilized as film-forming substrates. The essential oils were incorporated, and the films were prepared using two distinct techniques: Blending-stirring and emulsification-homogenization. The films were characterized by examining their surface morphology and systematically measuring key indicators including essential oil loading capacity, release rate, and antibacterial activity to comprehensively evaluate the impact of the preparation methods. Results The emulsification- homogenization process significantly enhanced the loading capacity of plant essential oils in the composite films and achieved a more sustained release profile compared to the blending-stirring method. The composite films prepared by emulsification-homogenization exhibited a more uniform dispersion of essential oils and a denser microstructure. These films also demonstrated stronger antibacterial activity against Staphylococcus aureus and Salmonella, as indicated by larger inhibition zones and a significant reduction in total bacterial count. Beef samples wrapped with the plant essential oil-based composite films maintained acceptable sensory scores after 60 hours of storage at 25?°C. Moreover, all composite films exhibited good environmental biodegradability, with degradation rates ranging from 82.83% to 90.55% over a 28-day period. Conclusion The emulsification-homogenization process effectively optimized the dispersion state of plant essential oils within the sodium alginate-gelatin composite film matrix and promoted a sustained-release behavior of the essential oils, thereby significantly enhancing the antibacterial efficacy of the composite films. This study provides an important foundation for the development of high-performance edible antibacterial packaging materials. The prepared plant essential oil-enhanced composite films demonstrate promising application prospects in extending food shelf life and improving food safety.