Properties of Milk Treated with High-Power Ultrasound and Bactofugation
1ATERA d.o.o., Cehovska Ulica 106, 42 000 Varaždin, Croatia
2Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10 000 Zagreb, Croatia
3ATERA-ICT d.o.o., Ulica Đure Sudete 14, 42 000 Varaždin, Croatia
Received: 26 March 2020
Accepted: 22 February 2021
milk properties, analysis, high-power ultrasound, bactofugation, milk treatment
Research background. Two methods of milk treatment were used, ultrasound (innovative method) and bactofugation, after which the physicochemical and sensory properties of the milk were examined, with the primary aim of achieving the quality and consistency of the pasteurized milk.
Experimental approach. Ultrasound power of 200 and 400 W and frequency of 24 kHz with constant wave cycle were used. Milk treatment duration was 2.5, 5, 7.5 and 10 min with sonification at temperature of 20 °C (room temperature) and thermosonification (ultrasound at temperature higher than room temperature) at temperature of 55 °C. The purpose of this study is to investigate the effect of high-power ultrasound combined with a slightly increased temperature on whole, skimmed and skimmed cow's milk pretreated with bactofugation.
Results and conclusions. The best sensory grade was achieved when milk was treated with ultrasound power of 200 W at 20 °C for max. 7.5 min. This research shows the potential of the applications of high-power ultrasound in dairy industry combined with bactofugation as a pretreatment of milk at a slightly increased temperature (up to 55 °C).
Novelty and scientific contribution. The application of these two treatments requires milder processing conditions than pasteurization, it is economical and more environmentally friendly technological process that preserves better nutritional values of milk, which is preferred by costumers.