Influence of the amount of rennet, calcium chloride addition, temperature, and high-pressure treatment on the course of milk coagulation
Influence of the amount of rennet, calcium chloride addition, temperature, and high-pressure treatment on the course of milk coagulation
复制标题
DOI：
10.17221/3537-cjfs
复制
发表时间：
2018-02
影响因子：
1.3
通讯作者：
A. Landfeld;P. Novotná;M. Houška
中科院分区：
文献类型：
--
作者：
A. Landfeld;P. Novotná;M. Houška
使用振荡流变仪Rheostress RS 150表征凝固的凝胶。考察了凝乳酶和CaCl2的添加量、温度和高压处理对凝胶性质的影响。评估凝血参数，即弹性模量G '、凝血开始时间t0和凝固时间常数τ。在监测增加凝乳酶和CaCl2的添加量以及温度升高的影响时，发现开始凝结的时间t0和凝结的时间常数t减小。极限剪切储能模量G'm ax在各种CaCl2量下几乎是恒定的，并随着温度的升高和凝乳酶的加入而适度降低。这种影响可能是由于极限值是外推到无穷大的回归参数。给定时间的模量的真实的值随着添加的氯化钙水平的增加而增加。经600 MPa的压力处理10 min的牛奶在凝固过程中形成更坚固的凝胶，剪切储能模量与未处理的牛奶相比几乎高出100%。凝固时间常数的值几乎减半。
Coagulated gel was characterised using an oscillation rheometer Rheostress RS 150. The influence was monitored of the additions of rennet and CaCl 2 , of temperature, and of high-pressure treatment on the properties of coagulated gel. Parameters of coagulation were assessed, i.e. elastic modulus G', the time of the start of coagulation t 0 , and the time constant of congealation τ. In monitoring the influence of increasing additions of rennet and CaCl 2 , and of temperature increase, it was found that the time of the start of coagulation t 0 and the time constant of congealation t decreased. The limiting shear storage modulus G' m a x was practically constant at various amounts of CaCl 2 and was moderately decreasing with increasing temperature and rennet addition. This effect was possibly caused by the fact that the limiting value is a regression parameter extrapolated to infinity. The real values of the modulus for a given time increased with increasing levels of calcium chloride added. Milk treated by the pressure of 600 MPa for 10 min formed, during coagulation, a more solid gel, the shear storage modulus being, almost by 100% higher as compared with untreated milk. Value of the time constant of congealation was practically halved.