聚赖氨酸在鲜切水果保鲜中的应用研究
时间:2017-06-19 09:02 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：聚赖氨酸(ε-PL)是继乳链球菌素之后产生的一种新型天然防腐剂，其化学组成是由人体必需氨基酸，赖氨酸构成的多肽,它经消化后又可变成单一的赖氨酸而成为人体营养的强化剂，故聚赖氨酸(ε-PL)作为食品防腐剂具有无毒副作用,安全性高。本课题研究聚赖氨酸(ε-PL)的抑菌特性，采用分光光度法、菌体重量等方法度量聚赖氨酸(ε-PL)对细菌和真菌的抑菌活性，实验结果表明：聚赖氨酸(ε-PL)的抑菌谱很广，细菌的最小抑菌浓度都不高于25mg/L，而啤酒酵母菌霉菌的最小抑菌浓度达到1500mg/L以上。热处理后聚赖氨酸(ε-PL)抑菌效果基本没有变化。本课题采用聚赖氨酸(ε-PL)对鲜切苹果进行处理，并用保鲜膜包装后在4℃储藏保鲜，实验表明：20mg/L的聚赖氨酸(ε-PL)对鲜切苹果中微生物有抑制作用，但聚赖氨酸与0.1%醋酸的复合抑菌效果最好。聚赖氨酸与醋酸的复配对水果硬度的影响最小。聚赖氨酸(ε-PL)应用于鲜切苹果中可以减轻水分的损失，聚赖氨酸与白芨多糖提取液的复配对水果水分的流失影响最小。经处理过的鲜切苹果L值高于对照，b值均低于对照，处理过的鲜切苹果有利于保持其色泽。10375 关键词： 聚赖氨酸(ε-PL)；抑菌性；复合；保鲜；苹果；质构仪 Polylysine bacteriostatic effect on fresh-cut apple research Abstract: Polylysine (ε-PL) is the second nisin generated after a new natural preservative, its chemical composition is determined by the essential amino acids, lysine polypeptide consisting of digestion and then it can be turned into a single lysine and become human nutrition fortifier, so polylysine (ε-PL) as a food preservative safe with no side effects.This paper studies on polylysine (ε -PL) antibacterial propertie. By spectrophotometry, the cell weight polylysine antibacterial activity against bacteria and fungi. The polylysine antibacterial characteristics. In this article the antimicrobial activity of polylysine，the effect of temperature condition on polylysine antimicrobial activity, and the antimicrobial activity of combination with sodium diactinic, glycine and acetic acid were studied. The results indicated that polylysine had a wide antimicrobial spectrum and the minimum inhibitory concentrations for the growth of bacteria below 25mg/L, and the minimum inhibitory concentrations for the growth of fungi below 1500mg/L. In this study, fresh-cut apple was treated with preservation solution, then preserved in 4℃ after packaged with clear plastic wrap. The results indicated that: 20mg/L polylysine have very good inhibitory action to the microorganism，but Polylysine complex with 0.1% acetic acid inhibitory effect is best and Polylysine complex acetate paired with minimal impact on fruit firmness. It can reduced the loss of the moisture. Polylysine complex acetate paired with minimal impact on fruit firmness.Polylysine complex Bletilla paired with fruit loss of water with minimal impact. After has processed fresh cuts the apple L value as well as b value is higher than the control. Keywords: Polylysine; Antimicrobial activity; Combination; Fresh-cut; Fruit 目 录 1 绪论 1 1.1 本课题的研究目的和意义 1 1.2 防腐剂目前研究状况 1 1.3 鲜切蔬果的保鲜 2 1.4 聚赖氨酸(ε-PL)的研究现状 2 1.5 聚赖氨酸(ε-PL)的概述 3 1.5.1 聚赖氨酸(ε-PL)的应用 3 1.5.3 聚赖氨酸(ε-PL)的生物学性质 5 1.5.4 聚赖氨酸(ε-PL)抑菌机理 5 1.5.5 聚赖氨酸(ε-PL)安全性 6 1.6 本课题研究的主要内容 6 (责任编辑：qin) |