利用表面张力系数和黏滞系数检测牛奶品质初探  

Preliminary study on the relationship between quality and surface tension and viscosity coefficient of milk

作　　者：景晨娟[1] 刘亚龙[1] 曹旭东[1] 

机构地区：[1]西北农林科技大学理学院,陕西杨凌712100

出　　处：《西北农林科技大学学报（自然科学版）》2012年第5期205-208,216,共5页Journal of Northwest A&F University(Natural Science Edition)

基　　金：国家自然科学基金项目(30471001)

摘　　要：【目的】探讨用牛奶表面张力系数和黏滞系数表征其内在品质的可行性。【方法】将鲜牛奶分为2组,1组置于(40±1)℃温度下,测量不同放置时间(0～12h)牛奶表面张力系数和黏滞系数的变化;另1组置于室温(25±1)℃条件下,研究不同掺水量(V水∶V总分别为0%,10%,20%,30%,40%,50%)对牛奶表面张力系数和黏滞系数的影响。【结果】随放置时间的不断延长,牛奶表面张力系数在0～1h急剧下降,1～7h先缓慢上升后下降,7～9h急剧上升,9～12h缓慢上升;而牛奶黏滞系数在0～11h变化不大,11h后呈剧烈上升趋势。牛奶表面张力系数和黏滞系数与掺水量之间均呈极好的线性关系,相关系数分别为0.943 6,0.954 9,其中掺水量达到10%时,牛奶品质即发生较大变化,其2个参数值分别显著下降4.05%和0.28%。【结论】表面张力系数较黏滞系数的灵敏度高,但稳定性较低;黏滞系数的灵敏度低,但稳定性较高。因此,可以将二者结合起来作为表征牛奶品质的物理指标。[Objective] The study was intended to explore the relationship between the quality of milk and its physical properties. [Method] For the first group, we detected the surface tension and viscosity co- efficient at different time （0-12 h） at （40± 1） ℃. For the second group, we added different amounts of water to milk （V water：Vtotal respectively was 0% ,10~//00,20% ,30% ,40% ,50%）,and then detected their surface tension and viscosity coefficient at （25±1） ℃. [Result] The first group＇s coefficient of surface ten- sion decreases sharply during 0--1 h, first rose, then went down slowly during 1- 7 h, then rose sharply again during 7--9 h,and then slowed down during 9--12 h. While the viscosity coefficient of pure milk re- mained almost constant during 0--11 h,it increased sharply after 11 h. In the second group,the relationships between the amount of added water and surface tension,viscosity coefficient were all liner, their correlation coefficients were 0. 943 6 and 0. 954 9 respectively. When the amount of water was 10% ,the qualily of milk changed greatly,and the surface tension and viscosity coefficient decreased 4.05% and 0.28% respectively. [Conclusion] The sensitivity of surface tension was better than viscosity coefficient, while the stability of surface tension was poorer than viscosity coefficient. So it ＇s a wiser way to combine them to reflect the quality of milk.

关 键 词：牛奶 品质检测 表面张力系数 黏滞系数 

分 类 号：TS252.7[轻工技术与工程—农产品加工及贮藏工程]