Ultrasound-assisted extraction of yerba mate leaves for the development of active additives in sports nutrition products

Abstract

This study aimed to develop yerba mate extracts (YME, Ilex paraguariensis) as activeingredients for a UVC-light-preserved (892 mJ/cm2; 50C) sports drink (SD) and thesports gel derived from it (SG). Aqueous ultrasound-assisted extractions (US; 20 KHz,750 W) of yerba mate leaves were performed at varying temperatures (T: 20, 40, and50 C) and acoustic energy densities (AED: 0, .11, and .23 W/mL). Total polyphenol(TPC) extraction kinetics were characterized using the Spiro and Jago, Linares, andPeleg models. The Spiro and Jago model accurately described the extraction kineticcurves. An empirical correlation was found between its rate constant and the variablesT and AED, reaching its maximum value at 50C–.23 W/mL, with no furtherTPC extraction beyond 4 minutes (4.20 g GAE/L). For comparison purposes, the conditions20C/.23 W/mL/7 min (3.33 g GAE/L) and 100C/0 W/mL/5 min (control)were also structurally and physiochemically compared. During the extraction, intraparticlediffusion was one of the major mechanisms limiting the extraction rate. WithAED and T, the intraparticle coefficient increased significantly. The US-assisted processgenerated extracts with greater wettability, hygroscopicity, more natural color,and similar content of relevant xanthin alkaloids and polyphenols, compared to thecontrol. SEM micrographs revealed that the US-assisted extract´s porosity increasedwith AED and T. The UV-C processing of SD was successfully validated throughmicrobial challenge assays. YME (20C/.23 W/mL/7 min) addition turned SD and SGgreener and raised their flavonoid content (SD: 5.2-fold and SG: 19.6-fold) and TPC(SD: 5.5-fold and SG: 5.3-fold). The DPPH and ABTS total antioxidant activity for SDand SG increased by 3.1–3.4-fold and 16.8–57.9-fold, respectively. SD-YM and SGYMwere well-accepted and described in a consumer field test. The developed YMEscan be a natural source of xanthine alkaloids and polyphenols, thereby replacing thesynthetic additives typically employed in sports nutrition products.Practical applicationsThe growing consumer belief in natural extracts´ ability to promote health and wellnessis driving the global market for botanical extracts. Yerba mate (Ilex paraguariensis St Hill) is a healthier alternative to coffee and tea, with higher antioxidant capacityand proven health benefits. The proposed extraction method eliminates the need forhigh temperature and prolonged treatments, preserving the nutritional value of yerbamate leaves. Furthermore, it eliminates waste generation, perfectly aligning with sustainablepractices. The optimized US-assisted extraction resulted in high-quality physicochemicalextracts with significant functional activity. Amateur athletes areincreasingly looking for products to enhance their performance that are both naturaland effective. In this context, the developed extracts can serve as natural additivesfor sports nutrition products, which typically include synthetic caffeine and othercompounds aimed at enhancing alertness, arousal, and energy.