壳聚糖-混合精油可食性薄膜对猪肉抗氧化性的研究
时间:2016-12-28 17:37 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：可食性薄膜包装是目前欧美地区新兴的安全性高的活性包装材料，不含有塑化剂。本课题构建了壳聚糖-丁香和鼠尾草混合精油薄膜，表征其物理、光学性状，并研究薄膜对生猪肉的保鲜效果（主要测定总菌数、pH值、过氧化酶，进行抗氧化试验（如TBA、DPPH试验）。试验结果表明：丁香和鼠尾草混合精油能显著增大壳聚糖薄膜的厚度，其厚度达到了0.15mm。透光率和不透明度方面，含鼠尾草油或混合精油的壳聚糖薄膜与对照组（不含精油）相比无明显差异，含有丁香油的壳聚糖薄膜的不透明度显著高于对照组(p<0.05)；丁香油和鼠尾草油单独或结合时均对壳聚糖薄膜亮度无显著(p<0.05)影响，壳聚糖薄膜保持较高的明度。在猪肉糜保鲜试验中，冷藏1周后，混合精油-壳聚糖薄膜处理的生猪肉的总菌数最小（5.93 Log cfu/g），且显著低于对照组（6.85 Log cfu/g），说明混合精油-壳聚糖薄膜的抑菌效果最好；不含或只含单种精油的壳聚糖薄膜也表现出一定的抑菌效果，但是不显著。随着储藏时间的增加肉糜的pH也增加，混合精油薄膜处理的肉糜pH增加的程度最小，说明延缓肉腐败的效果最好。TBA和DPPH试验结果具有高度一致性，都表明不同精油薄膜保藏的肉糜抗氧化性与对照组存在显著性差异，其中，混合精油薄膜处理组的抗氧化性更强。通过上面这些结论可知，复合薄膜能有效用于生猪肉糜的冷藏，延长生猪肉的货架期。4842 关键词:植物精油；壳聚糖薄膜；理化性质；抑菌；抗氧化 Characterization of chitosan films incorporated with clove and sage essential oils and their antioxidant activity in raw pork Abstract: Currently, edible film is the emerging high security of active packaging materials in European and American, does not contain plasticizers. In this paper, chitosan films incorporated with clove and/or sage essential oil were prepared and characterized. Their preservation effects （total viable count, pH）on the raw pork were also studied. The results indicated that clove - sage mixed essential oils significantly (p<0.05) increased the thickness of chitosan films, reaching 0.15 mm. For transmittance and opacity, chitosan films incorporated with sage essential oil or a mixture of essential oils did not differ significantly with that of the control group (p<0.05). Chitosan film incorporated with clove essential oil had a higher opacity value than the control film. There was no difference in the lightness among all the treatments. The raw pork treated with chitosan film containing a mixture of oils showed a lowest total viable count of 5.93 Log cfu/g （the control group was 6.85 Log cfu/g）. In addition, the pH value of all pork slices was increased during the storage. The chitosan-mixed oils film could effectively delay the increase of pH. The results of TBA and DPPH assay were in high accordance. All films exhibited a good antioxidant activity in pork, compared with the control. It was noted that the chitosan films containing mixed oils had the strongest antioxidant capacity in pork slices. In sum, the chitosan film enriched with mixed essential oils has a great potential in maintaining the quality of raw pork during refrigerated storage at 4 ℃. Keywords: essential oils; chitosan film; physiochemical properties; antibacterial; antioxidant activity 目录 1引言 1 1.1 我国肉制品工业的发展现状 1 1.1.1 肉制品的生产量 1 1.1.2 肉制品的工业存在的问题 1 1.2 肉制品的腐败变质 1 1.2.1 肉制品腐败变质的特征 1 1.2.2肉制品腐败变质的原因与条件 2 (责任编辑：qin) |