الفهرس 
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Abstract
Dairy fermented products are one of the most popular food products in the world and the fermentation process is the basic step for producing fermented products.
During the production of fermented products, it is important to control the fermentation process and processing parameters involved, such as temperature and pH. The aim of the project was to study the kinetics of the fermentation process of bovine milk with isothermal calorimetry and to evaluate the effect of genetic factors and the relative amount of β-Lactoglobulin and casein number (selection criteria) on the compositional, technological properties and reaction rates. Glucono-δ-lactone (GDL) was used for direct acidification of milk to evaluate the effect of temperature and GDL concentration on the process. The heat produced during the acidification was measured by isothermal calorimetry. Different heat production rates were found with different temperatures and GDL concentrations. In addition, pH measurements were performed in parallel with isothermal measurements. As a reference, yoghurt with a mixed culture of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. Bulgaricus was used in eight different concentrations as GDL. This study indicated that the reaction rate (heat production rate) during acidification was proportional to GDL concentration and a relation was found with the pH decrease. The reaction was modeled as a first-order reaction, and the relations between bovine milk acidification, GDL concentration and pH decrease gave an increased understanding of the fermentation kinetics of bovine milk.
In addition, different individual milk samples were analyzed for getting a detailed knowledge about milk protein genotypes and protein contents effect on the technological properties and heat production rate. The heat production rate was measured in individual milk samples. It was observed that milk protein genotypes (mainly κ-casein genotypes) and casein number had an impact on compositional and technological properties.