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 of milk, after which the physicochemical and sensory properties of the milk were examined, with the primary aim of achieving consistency of the properties of the milk with pasteurization.
Experimental approach. Ultrasound power levels of 200 and 400 W and frequency of 24 kHz with constant 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 was to investigate application of high power ultrasound, combined with a slightly increased temperature on: whole, skimmed and skimmed bactofugated cow's milk.
Results and conclusions. The best sensory grade was achieved when milk was treated with ultrasound power of 200 W, at 20 °C and the processing time was max. 7.5 min. This research shows potential of applications of high-power ultrasound in dairy industry, when combined with bactofugation technology as a pre-treatment for milk and with a slightly increased temperature (up to 55 °C).
Novelty and scientific contribution. The application of these two technologies leads to milder processing conditions than pasteurization, an economical and more environmentally friendly technological process preferred by costumers and consumers, but also to a nutritionally beneficial composition of milk.