Ahmadi Azam, Ahmadi Parisa, Ehsani Ali
Student Research Committee Tabriz University of Medical Sciences Tabriz Iran.
Department of Food Sciences and Technology Faculty of Nutrition and Food Sciences Tabriz University of Medical Sciences Tabriz Iran.
Food Sci Nutr. 2020 Aug 31;8(10):5461-5473. doi: 10.1002/fsn3.1812. eCollection 2020 Oct.
The casting method was employed to prepare gelatin-based nanocomposite films containing different concentrations of cellulose nanofiber (CNF) as a reinforcement filler (2.5%, 5%, and 7.5% w/w of gelatin) as well as zinc oxide nanoparticles (ZnO NPs) as an antimicrobial agent (1%, 3%, 5%, and 7% w/w of gelatin). The results showed that the incorporation of 5% CNFs (optimum concentration) significantly boosted the films' stiffness (YM; by 47%) and strength (TS; by 72%) but decreased its flexibility (EAB; by 28%), water vapor permeability, and moisture absorption. The best G/CNF film antibacterial activity was provided by the 5% concentration of ZnO NPs according to the disk diffusion assay; Gram-positive bacteria were inhibited significantly more than Gram-negative bacteria. The antimicrobial efficacy of the G/CNF/ZnO NPs film as a food packaging material was assessed via counts of and inoculated on chicken fillets (as a food model) in the treatment (G/5% CNF/5% ZnO) and control groups (plastic bag). The antibacterial film led to a significant reduction in the bacterial load of the chicken fillets ( < .05), especially against the Gram-positive strain. This study illustrated that G/CNF/ZnO NPs films can be utilized as active packaging to prolong the shelf life of different perishable foods such as meat.
采用浇铸法制备了基于明胶的纳米复合薄膜,其中含有不同浓度的纤维素纳米纤维(CNF)作为增强填料(占明胶重量的2.5%、5%和7.5%)以及氧化锌纳米颗粒(ZnO NPs)作为抗菌剂(占明胶重量的1%、3%、5%和7%)。结果表明,加入5%的CNF(最佳浓度)显著提高了薄膜的硬度(杨氏模量;提高了47%)和强度(拉伸强度;提高了72%),但降低了其柔韧性(断裂伸长率;降低了28%)、水蒸气透过率和吸湿性。根据纸片扩散法,5%浓度的ZnO NPs赋予了最佳的G/CNF薄膜抗菌活性;革兰氏阳性菌比革兰氏阴性菌受到的抑制更显著。通过对处理组(G/5% CNF/5% ZnO)和对照组(塑料袋)接种在鸡胸肉(作为食品模型)上的 和 的计数,评估了G/CNF/ZnO NPs薄膜作为食品包装材料的抗菌效果。抗菌薄膜使鸡胸肉的细菌载量显著降低( <.05),尤其是对革兰氏阳性菌株。本研究表明,G/CNF/ZnO NPs薄膜可作为活性包装材料用于延长肉类等不同易腐食品的保质期。