Development of an Orange-Tangerine Juice Treated by Assisted Pilot-Scale UV-C Light and Loaded with Yerba Mate: Microbiological, Physicochemical, and Dynamic Sensory Studies

Abstract

An orange-tangerine juice processed by pilot-scale UV-C light (390 mJ/cm2) assisted by mild heat (UV-C/H,50 °C) and enriched with yerba mate (YM) extract (UV-C/H + E) or encapsulated YM extract (UV-C/H + EE) is proposed. The inactivation of Escherichia coli, Lactiplantibacillus plantarum, and Saccharamyces cerevisiae was assessed. Juice samples were analysed for polyphenol content (TPC), total antioxidant activity (TAA), colour, turbidity, and °Brix along refrigerated storage (4 °C; 20 days). For the UV-C/H + E and UV-C/H + EE juices, dynamic consumer profiling studies were performed. According to the challenge study, UV-C/H induced high microbial inactivation (4.9–5.8 log-reductions). TPC (0.059 ± 0.002 mg GAE/mL) and TAA (6.3 ± 0.2 mg TroloxEq/mL) in the UV-C/H + EE juice were 2.1 and 1.6 times greater than the untreated ones, respectively. The UV-C/H + E juice displayed a slightly lower increase in TPC (0.045 ± 0.020 mgGAE/mL), but similar TAA (7.1 ± 0.3 mgTroloxEq/mL), compared to the UV-C/H + EE juice. Therefore, the encapsulation procedure prevented YM extract from TPC degradation. UV-C/H did not alter juice colour while YM addition increased its turbidity. Frequent consumers of YM tea showed a high willingness to try the juice. A cluster sensory analysis revealed that one group of consumers was interested in the sour and herbal aroma of the UV-C/H + E and UV-C/H + EE juices. The T-CATA question showed that the sweetness and herbal aroma of the UV-C/H + E juice were better perceived with sips; whereas, UV-C/H + EE juice perception shifted from fruity, herbal aroma, and sweet to intense taste, bitterness, and pleasant aroma. Thus, YM extract encapsulation also contributed to mask juice bitterness in the first sip while highlighting its sweetness. However, as juice intake proceeded, the panelists perceived juice bitterness more intensely.