Polyphenol content, color and acceptability of carrot pickles added with yerba mate powder extract

Abstract

Yerba mate (Ilex paraguariensis Saint Hilaire) processing generates large amounts of powder that are not added to the final product. This powder has a similar composition to commercial yerba mate and it can be used to extract bioactive compounds. The work aims to prepare carrot pickles added with yerba mate powder extract to improve the Total Phenol Content (TPC) of the final product. The TPC and the color of the pickles were studied in the carrots and the liquid brine for a total of 120 days, by testing two storage temperatures (25 and 45 °C). The TPC was determined by the Folin-Ciocalteu method, and color parameters L*, a*, and b* were measured using a colorimeter. In addition, a sensory acceptability analysis was performed at the end of storage. Pickled carrots without extract addition showed significant losses of polyphenols during storage. The addition of increasing amounts of yerba mate powder extract significantly improved this parameter, thus achieving TPCs even higher than those of fresh carrots. The pasteurization, the addition of extract, and storage caused variations in the color of both fractions of the pickle, especially in the formulations with a higher proportion of yerba mate. However, the color changes were more important in the liquid brine, while in the carrots the variations were minimal. Sensory acceptability tests showed that the addition of extract did not influence the flavor of the pickles but caused changes in color acceptability. However, the product was accepted by consumers. The results showed that yerba mate powder extract can be added in small amounts into other foods for improving their TPC while causing minor modifications in color and sensory acceptability.