Izvorni znanstveni članak
Influence of high power ultrasound on rheological and foaming properties of model ice-cream mixtures
Verica Batur
Vesna Lelas
Anet Režek Jambrak
Zoran Herceg
orcid.org/0000-0003-3967-6676
; Prehrambeno-biotehnološki fakultet Sveučilišta u Zagrebu, Zagreb, Hrvatska
Marija Badanjak
Sažetak
This paper presents research of the high power ultrasound effect on rheological and foaming properties of ice cream model mixtures. Ice cream model mixtures are prepared according to specific recipes, and afterward undergone through different homogenization techniques: mechanical mixing, ultrasound treatment and combination of mechanical and ultrasound treatment. Specific diameter (12.7 mm) of ultrasound probe tip has been used for ultrasound treatment that lasted 5 minutes at 100 percent amplitude. Rheological parameters have been determined using rotational rheometer and expressed as flow index, consistency coefficient and apparent viscosity. From the results it can be concluded that all model mixtures have non-newtonian, dilatant type behavior. The highest viscosities have been observed for model mixtures that were homogenizes with mechanical mixing, and significantly lower values of viscosity have been observed for ultrasound treated ones. Foaming properties are expressed as percentage of increase in foam volume, foam stability index and minimal viscosity. It has been determined that ice cream model mixtures treated only with ultrasound had minimal increase in foam volume, while the highest increase in foam volume has been observed for ice cream mixture that has been treated in combination with mechanical and ultrasound treatment. Also, ice cream mixtures having higher amount of proteins in composition had shown higher foam stability. It has been determined that optimal treatment time is 10 minutes.
Ključne riječi
ultrasound; ice cream model mixture; rheological properties; foaming
Hrčak ID:
49405
URI
Datum izdavanja:
22.3.2010.
Posjeta: 2.898 *