M. Tita, R. M. Iancu, O. Tita, O. Ketney, A. Dabija, I. Sion
Tuesday 6 August 2013 by Libadmin2013

References: 13th SGEM GeoConference on Nano, Bio And Green – Technologies For A Sustainable Future, www.sgem.org, SGEM2013 Conference Proceedings, ISBN 978-619-7105-06-3 / ISSN 1314-2704, June 16-22, 2013, 347 - 352 pp


The milk coagulation is a very important operation during the technological processing of cheese. The curd that is obtained either through acidification or biocatalysis represents a complex system with an instable physical structure, formed by a protein network in which fat and whey are incorporated. Bearing in mind the importance of this operation, we have realized two coagulation methods during our study: - by acidic precipitation that takes a long time even at an optimum temperature, using the natural acidification of milk and with help from the citric acid; - by enzymatic biocatalysis using curd. The conditions of administration for cow milk as raw material has been analyzed, a control of antibiotics and antiseptic substances been executed using the Neal-Galbert methods, the analysis of the main components of milk using the Ekomilk apparatus and the microbiological determination of the load factor of the milk – reductase test. The coagulation time has also been observed, the aspect of the formed curd, the aspect of the obtained whey and the behavior of the obtained curd during a 9 days period. The 3 types of curd that have been obtained have been analyzed from a sensorial, physical-chemical point of view: acidity, protein and lactose content, as well as the activity of waters using the Lab Master-aw system, because the activity of waters is important and can influence the development of microorganisms.

Keywords: technological characterization, protein network, biocatalysis, components, the curd.