Formulation of fermented tea containing Jerusalem artichoke extract using response surface methodology

Abstract

Currently, the development of functional beverages has gained growing interest in food biotechnology. This study focused on developing a tea enriched through the fermentation of Jerusalem artichoke (JA) extracts, which are known to contain significant prebiotics such as inulin and fructo-oligosaccharides. The fermentation was conducted using a novel probiotic strain, Lactobacillus LA-5. The study utilized three factors to optimize the functional properties of the beverage: the amounts of JA extract (ranging from 25% to 75% v/v), the sugar content (5% to 10% w/v), and the fermentation time (spanning 4 to 8 hours). The density, titratable acidity, and viable cell count of the beverage were determined. Response surface methodology and the Box-Behnken design were utilized, with bacterial growth, total phenolic content, and pH serving as the responses. The eleven production conditions identified include 10 grams of sucrose, 35 to 37.5 milliliters of JA extract (v/v, %), and a fermentation time ranging from 6.2 to 6.92 hours. These conditions resulted in the highest optical density values (0.746 to 0.757), total phenolic content (165.1 to 166.7 mg GAE/g), and a pH of 4.09. The product formulated in this study could be of interest for consumers, especially for tea-consuming people.