摘要
目的:制备降解(低分子质量)壳聚糖并考察对肉品的保鲜效果。方法:采用H2O2均相氧化降解壳聚糖,以乌氏黏度法测其黏均分子质量;用牛津杯法测定降解壳聚糖对大肠杆菌、金葡菌、霉菌的抑菌圈直径;喷洒降解壳聚糖溶液于肉品表面,用表面涂抹法测定肉品在25℃放置过程中菌落总数的变化。结果:影响降解壳聚糖分子质量大小的因素顺序为:时间>温度>H2O2浓度>HAc浓度;在反应时间6h、温度75℃、H2O2体积分数6%和HAc体积分数4%时,可得黏均相对分子质量为2300的可溶性壳聚糖;降解壳聚糖对大肠杆菌、金葡菌的抑菌率高于未降解壳聚糖,而对霉菌的抑菌性变化不大;经质量分数6%、黏均分子质量2300壳聚糖溶液喷洒肉品表面后,鲜猪肉4d、熟猪肉6d可保持良好色泽、弹性、气味,且菌落总数符合GB2726-2005要求。结论:低分子质量壳聚糖可作为肉品防腐保鲜剂。
Objective: To prepare the chitosan with low molecular weights and to study their preservative effects on meat. Methods: The degradation of chitosan was prepared by means of the oxidation of H2O2, and the molecular weight of chitosan was determined by Ubbelohde viscometer. The antibacterial activities of the chitosans against E. coli, S. aureus and moulds were determined by oxford plate assay system. The meat coated by chitosans solution was stored at room temperature, and their total colonies of meat were determined by smear method. Results: The factor orders of influcing chitosan's molecular weights were as follows: the reaction time, the temperature, the concentration of H2O2 and HAc. Under the conditions of reaction time 6 h, temperature 75℃, the concentration of 6% H2O2 and 4% HAc, the chitosan with viscosity average molecular weight of 2 300 was prepared. The inhibition efficiency of the degrading chitosans against S. aureus, E. coli were greater than undegraded ones, but they had little influence on moulds The fresh meat groups coated with 6% chitosan with molecular weight of 2 300 could keep good colour, lustre, elastic and smell for four days, and the cooked meat groups could prolong to six days, and their total colonies accorded with GB2726-2005. Conclu- sions: Chitosan with low molecular weight could be used as the antiseptic and preservative for meat.
出处
《中国食品学报》
EI
CAS
CSCD
北大核心
2012年第5期130-136,共7页
Journal of Chinese Institute Of Food Science and Technology
关键词
壳聚糖
H2O2均相降解
抑菌性
猪肉
菌落总数
Chitosan
homogeneous oxidation degradation using H2O2
antibacterial activity
meat
total colonies