Influence of tribomechanical micronization and hydrocolloids addition on enthalpy and apparent specific heat of whey protein model solutions

• Main Authors: Zoran Herceg, Vesna Lelas, Suzana Rimac-Brnčić
• Format: Article
• Language: English
• Published: Croatian Dairy Union 2002-01-01
• Series: Mljekarstvo
• Subjects: tribomechanical micronization; thermophysical properties; whey proteins concentrate; hydrocolloids
• Online Access: http://hrcak.srce.hr/index.php?show=clanak&id_clanak_jezik=3560

Knowledge of thermophysical properties, especially the phase transitions temperature, specific heat and enthalpy, are essential in defining the freezing process parameters as well as storage conditions of frozen food. In this work thermophysical properties of 10% model solutions prepared with 60% whey protein concentrate (WPC) with various hydrocolloids addition (HVEP, YO-EH, YO-L i YO-M) were investigated. Powdered whey protein concentrate was treated in equipment for tribomechanical micronization and activation at 40000 rpm (Patent: PCT/1B99/00757) just before model solutions preparation. Particle size analysis was performed using Frich –laser particle sizer “analysette 22”. The phase transition temperatures were determined by differential thermal analysis (DTA), while specific heat and enthalpy were calculated according to several mathematical equations. The results have shown that, due to tribomechanical treatment, certain changes in thermophysical and energetic properties of materials occurred. Tribomechanical treatment affects changes in granulometrical composition of WPC which result in higher abilities of reactions with hydrocolloids in model solutions and significant changes in thermophysical properties of the mentioned models.