A Comprehensive Study on the Development of an Isotonic Sports Drink Preserved by UV-C Light Assisted by Mild Heat and Loaded with Yerba Mate (Ilex paraguariensis St. Hill.) Extract

Abstract

A unique isotonic sports drink (ISD) was created in this study using a pilot-scaleshort-wave ultraviolet light (UV-C, 892 mJ/cm2, 20 °C) assisted by mild heat (UV-C/H, 534mJ/cm2, 50 °C), which was followed by the addition of yerba mate (Ilex paraguariensis) extract(YME). Consumer perception and microbiological and physicochemical stabilityduring refrigerated storage (4 °C/23 d) were assessed for the ISD. Alicyclobacillus acidoterrestris(AA) spores and cocktails of yeasts and Escherichia coli were considerably inactivatedby UV-C/H. The TEM and SEM micrographs showed that AA evidenced sustainedsevere structural damage. Furthermore, UV-C/H completely inactivated the native microbiota,while YME incorporation increased the initial aerobic mesophilic and mold-andyeastpopulations by 0.48 and 0.70 log cycles, remaining stable during storage. YME additionenhanced total polyphenols, flavonoids and antioxidant activity by 2.7–3.7, 16.5–16.7 and 6.6–24.0 times compared to the untreated ISD and ISD-UVC/H samples. Exceptfor sedimentation and turbidity, the other physical characteristics mostly did not change(going from 1494 ± 382 to 2151 ± 106 NTU). The initial 5-HMF value in the ISD was raisedby UV-C/H treatment and YME addition. Notwithstanding, it stayed below the allowedthreshold throughout storage. ISD-UVC/H+YME had a high overall acceptability score;60% of panelists gave the drink a score of seven or higher. Additionally, the herbal tasteof YME was well liked, and its bitterness was perceived as mild. These findings suggestthat including YME and the UV-C/H treatment can produce an ISD of superior qualitywith distinct sensory attributes.