Chang Shun-Hsien, Chen Ying-Ju, Tseng Hsiang-Jung, Hsiao Hsin-I, Chai Huey-Jine, Shang Kuo-Chung, Pan Chorng-Liang, Tsai Guo-Jane
Institute of Food Safety and Risk Management, National Taiwan Ocean University, Keelung 20224, Taiwan.
Department of Food Science, National Taiwan Ocean University, Keelung 20224, Taiwan.
Polymers (Basel). 2021 Feb 25;13(5):696. doi: 10.3390/polym13050696.
This research prepared chitosan-PLA plastic films by extrusion, analyzed the physical and mechanical properties and antibacterial activity of the fabricated plastic films, and used them to preserve grouper fillet. We added chitosan (220 kDa, 93% DD) in the weight ratio of 0.5-2% into the PLA to prepare the chitosan-PLA films. With the increasing chitosan dosage, both the water vapor transmission rate and moisture content of chitosan-PLA films increased. Among the three doses of chitosan (0.5%, 1%, and 2%) added to PLA, 0.5% chitosan-PLA film had the highest antibacterial activity. This plastic film had an inhibitory efficiency of over 95% against , and . The action of covering the fish fillet with 0.5% chitosan-PLA film significantly reduced several microbes' counting (i.e., mesophiles, psychrophiles, coliforms, , , and ) and total volatile basic nitrogen (TVBN) value in the grouper fillets stored at 4 °C. Thus, such action prolongs the fish fillets' shelf life to up to at least nine days, and this 0.5% chitosan-PLA film shows promising potential for preserving refrigerated fish.
本研究通过挤出法制备了壳聚糖-聚乳酸塑料薄膜，分析了所制备塑料薄膜的物理机械性能和抗菌活性，并将其用于保存石斑鱼鱼片。我们按0.5%-2%的重量比向聚乳酸中添加壳聚糖（220 kDa，脱乙酰度93%）以制备壳聚糖-聚乳酸薄膜。随着壳聚糖用量的增加，壳聚糖-聚乳酸薄膜的水蒸气透过率和水分含量均增加。在添加到聚乳酸中的三种壳聚糖用量（0.5%、1%和2%）中，0.5%壳聚糖-聚乳酸薄膜具有最高的抗菌活性。这种塑料薄膜对[此处原文缺失具体菌种名称]、[此处原文缺失具体菌种名称]和[此处原文缺失具体菌种名称]的抑制效率超过95%。用0.5%壳聚糖-聚乳酸薄膜覆盖鱼鱼片的行为显著降低了在4℃下储存的石斑鱼鱼片中几种微生物的计数（即嗜温菌、嗜冷菌、大肠菌群、[此处原文缺失具体菌种名称]、[此处原文缺失具体菌种名称]和[此处原文缺失具体菌种名称]）以及总挥发性盐基氮（TVBN）值。因此，这种行为将鱼鱼片的货架期延长至至少九天，并且这种0.5%壳聚糖-聚乳酸薄膜在保存冷藏鱼方面显示出有前景的潜力。
