The infusion preparation processes can be modified in order to provide drinks characterised by a richer chemical composition and more desirable sensory parameters. Interesting is the use of ultrasound in the process of making infusions from various materials of plant origin. The objective of the research study was to assess the impact of the infusion preparation method on the concentration of polyphenols and caffeine. The infusions of peppermint, common chamomile and coffee were made using variable parameters of time and temperature; also the infusions were brewed traditionally and with the application of ultrasound. It was shown that the duration of brewing process and water temperature impacted the concentration of active substances in the infusions prepared as did the use of sonication. It was proven that the application of sonication had a significant effect on the increase in the concentration of polyphenols (by 7 ÷ 54 %) and caffeine (by 3 ÷ 20 %) in the infusions made. The sonication- supported brewing process made it possible to make beneficial infusions from both the herbs tested and the coffee at a lower water temperature (70 ºC) and during a shorter brewing time. Ultrasound is an interesting technique that can significantly improve the quality of herbal and coffee extracts in terms of the content of active substances. The utilization of ultrasound provides the potential to make infusions with similar concentrations of active substances using a smaller quantity of raw material or during a shorter time compared to the traditional way of brewing.
peppermint, chamomile, coffee, infusions, ultrasound, polyphenols, caffeine