契达干酪应力松弛特性与成熟度相关性研究

Study on correlation between stress relaxation and ripening Index of cheddar cheese

测定了契达干酪不同成熟期样品的应力松弛时间、弹性模量和成熟度指数,分析了其与干酪成熟度之间的相关性。结果表明,弹性模量随成熟期呈降低趋势。应力松弛时间随成熟期先增大后降低,并在7出现最大值。7~90d样品应力松弛时间呈单调递减。各成熟期样品的应力随测试时间的衰减规律符合对数规律。随成熟期的增加,可溶性氮质量分数pH4.6-SN和12%TCA-SN均呈增大趋势,增大幅度分别为18.07%和8.2%。弹性模量和应力松弛时间与成熟度指数分别呈极显著和显著线性相关。

Changes of stress relaxation time, elastic modulus and ripening index of Cheddar cheese were measured, and the correlation between these rheological parameters and ripening index was analyzed. The results showed that elastic modulus of Cheddar cheese decreased with the ripening time, this may reflect the cheese internal network structure going to be weaked during the ripening and the elastic component going to be reduced. Stress relaxation time at the initial period increased and it reached a maximum value of 169.85 s at 7 d, and then reduced monotonically. The stress decay regulation obeyed a logarithmic decay law for each cheese sample。The soluble nitrogen content tended to increase during ripening, the increase rates of pH4.6-SN and 12%TCA-SN were 18.07 % and 8.2 % respectively. Stress relaxation time,elasticmodulus and ripening index showed a correlation significantly.