文章基本信息

标题：Acid gelation of colloidal calcium phosphate-depleted preheated milk
本地全文：下载
作者：Marie-Hélène Famelart ; Géraldine Gauvin ; Denis Pâquet 等
期刊名称：Dairy Science & Technology
印刷版ISSN：1958-5586
电子版ISSN：1958-5594
出版年度：2009
卷号：89
期号：3-4
页码：335-348
DOI：10.1051/dst/2009014
语种：English
出版社：EDP Sciences
摘要：This study aimed at understanding the role of colloidal calcium phosphate (CCP) in acid gelation of milk. Milks were depleted in Calcium (Ca) by dialysis against milk permeate containing a cation-exchange resin. Dialysed milks were then heated (90 $^{\circ}$C-10 min) and acidgelled at 42 $^{\circ}$C with a yoghurt culture. Minerals, total and soluble protein contents, pH and optical density were measured in unheated and heated dialysed milk, together with diameters and $\zeta$-potentials of particles. Dialysis of milk led to a dissociation of 45% total Ca and 30% total phosphorus, to an increase in sodium content and pH of milk, to lower turbidity and $\xi$-potential, but did not change the casein particle size. Soluble Ca and casein-bound Ca were removed from milk, CCP being removed increasingly, while Ca removed from the phosphoserine residues increased very little during the dialysis experiments. Maximal dissociation of $\alpha_{\rm s1}$- and $\alpha_{\rm s2}$-casein was 20%, while that of $\beta $- and $\kappa $-casein was 35–40% of total at the end of dialysis, and it increased after heating, especially for $\kappa $-casein. The pH value at which the milk sample begins to gel increased for low mineral depletion rates but decreased for higher depletion levels. This was due to the increase in the pH value of milk and in the $\kappa $-casein dissociation. The elastic modulus decreased in samples at the lowest depletion and then levelled off, which suggested that the phosphoserine-bound Ca played a critical role in the formation of acid gels.
关键词：olloidal calcium phosphate;CCP;acid milk gel;dialysis