真空蒸镀Ag_2O/HDPE膜对奶酪的保鲜性研究

Freshness Preservation of Cheese with Ag-Coated High Density Polyethylene Membrane

在自制的高密度聚乙烯(HDPE)膜上真空蒸镀氧化银(Ag_2O)得到Ag_2O/HDPE复合膜,考察该膜的抗菌性,并对奶酪进行包装,考察Ag_2O/HDPE膜对奶酪的保鲜性。结果发现,Ag_2O/HDPE膜对大肠杆菌和金黄色葡萄球菌均有强抗菌性。相比于HDPE膜,真空蒸镀Ag_2O/HDPE膜能有效抑制奶酪中微生物的生长、延缓奶酪贮藏期内感官品质的下降,包装7 d的奶酪的pH值更接近标准样,Ag_2O/HDPE膜对奶酪具有一定的保鲜性。此外热重分析结果表明,不同包装材料对奶酪的热分解速率有一定影响,在320℃附近,真空蒸镀Ag_2O/HDPE膜所包装奶酪的热失重比纯HDPE膜所包装奶酪的热失重小。

A novel type of freshness preservation material, the high density polyethylene （HDPE） membrane surface- modified with vacuum deposited Ag2O coatings, was developed to preserve fresh cheese. The impact of the Ag2O-eovered HDPE on the freshness preservation and antibacterial property against bacteria, including but not limited to Escherichia coli and staphylococcus aureus, was experimentally investigated with thermal gravimetric analysis. The preliminary results show that when it comes to freshness preservation with cheese, the Ag2O/HDPE membrane outperforms HDPE membrane, because Ag20 coating is capable of inhibiting microbe growth and delaying declination of quality and pH value of the packaged cheese.In addition,Storage in air for 7days and measured at about 320℃,the thermal weight loss of the cheese preserved with Ag2O/HDPE membrane was found to be lower than that of the cheese packaged with HDPE,as shown in TGA results.