Résumé:
In the goal to appreciate faculties to the transformation produces some derivative of the mixture (cool milk / recombinated milk) used in our country as palliative to the deficit of the production in raw milk, we achieved tests of cheese manufacture to dough soft Camembert type in the Dairy of Draa Ben Khedda while especially interesting us to the assessment of proteolytic activity taking place during the phase of refinement and the storage refrigerated of this cheese. This activity is measured by the free amino grouping dosage (method using a specific reactif: the TNBS) and by the follow-up of casein behaviour electrophoretic in Page - Urea. The impact of the pasteurization treatment (85°C during 20 dry) on the milk of departure and the nature of this last have been examined also. The achieved analyses showed that the mixed milk (mixture to equal parts between
the cool milk and milk recombiné) permits, while correcting the rate weak proteic of the raw milk collected locally, to improve its value nutritional and its technological faculties. Nevertheless, electrophoretic pattern’s of seriqueses proteins in Page - Native as well as the soluble protein dosage after the treatment of pasteurization revealed a strong induced denaturation rate by this last and valued to about 30% in the case of milk recombiné used only. Concerning tea appreciation of tea refinement phase, however tea assessment of proteolytic activity is combinated to tea development of microorganisms, so much at tea level of tea superficial crust that in depth of tea derivative product tea gotten results showed that for tea two types of cheese considered (milk-based expenses solely however of tea mixed milk), tea proteolysis is pronounced more in surface that inside tea Camembert and this some either tea length of refinement considered. This activity, that is major after the sixth day of refinement, incomplete home after 12 days (time of maturation exercised to the unit. The extension of the refinement length at 15 and 210 days put besides in relief this insufficiency. Besides, the refrigerated storage doesn't seem to be a way appropriated for the characteristic organoleptiques expression searched for of the Camembert.