Original scientific paper
Influence of High Intensity Ultrasound Treatments on Physical Properties of Sheep Milk
Tomislav Bosiljkov
; Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10000 Zagreb, Croatia
Branko Tripalo
; Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10000 Zagreb, Croatia
Damir Ježek
; Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10000 Zagreb, Croatia
Mladen Brnčić
; Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10000 Zagreb, Croatia
Sven Karlović
; Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10000 Zagreb, Croatia
Filip Dujmić
; Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10000 Zagreb, Croatia
Abstract
In this study, research was based on influence of high intensity ultrasound on inhomogeneous sheep milk. Ultrasonic processor (maximal nominal power – 100W) with the constant frequency of 30 kHz was used for milk homogenization. Changes on temperature, pH – value, density, viscosity and absorbance (500nm) are followed by given process parameters: amplitude (A = 20, 60 and 100 %); time of treatment (t = 2, 6, 10 and 15 minutes), full cycle (c = 1), probe diameters (d = 7, 10 and 14 mm). Statistical analysis was conducted and infl uence of process parameters and temperature was expressed over p – value (p<0.05; ANOVA; ANCOVA). Applications of different probe diameter have significant influence on all observed physical properties. Longer time of treatment and amplitude showed significant infl uence on temperature, absorbance and changes on viscosity of sheep milk, while on pH – value and density has no infl uence. Analyses of covariance (ANCOVA) showed significant
influence of the temperature on increasing of absorbance and viscosity, while temperature has no influence on pH – value and density of ultrasonically treated milk.
Keywords
ultrasound; sheep milk; temperature; physical properties
Hrčak ID:
82778
URI
Publication date:
6.6.2012.
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