Preparation of Suaeda Tea Through Semi-Solid Fermentation Utilizing Kluyveromyces marxianus, Komagataeibacter europaeus, and Acetobacter schutzenbachii: Physicochemical Characteristics, Process Optimization, and Antioxidant Activity

Suaeda salsa, an annual herb belonging to the genus Suaeda within the Chenopodiaceae family, is highly salt-tolerant and can thrive in large quantities on saline and alkaline soils. This study presents a novel fermentation technique to produce Suaeda tea, utilizing a synergistic blend of microbial agents: Kluyveromyces marxianus, Komagataeibacter europaeus, and Acetobacter schutzenbachii. The resulting tea demonstrates a potent antioxidant capacity, with a hydroxyl radical scavenging rate of 64.2% and an exceptional 1,1-diphenyl-2-picrylhydrazyl radical (•DPPH) scavenging capacity of 83.3%, along with increased ferric ion reduction/antioxidant power (FRAP) reducing power (1.82), indicating its superior antioxidant profile. Through the comparison of different microbial strain combinations under varying process parameters such as fermentation temperature and duration, the experiment revealed that fermentation at 37 °C for 24 h results in the highest concentrations of tea polyphenols (TPs) (≥10.87 mg/mL) and free amino acids (26.32 mg/100 mL). The quality of the fermented Suaeda tea meets the stringent GB/T 21733-2008 standards for tea beverages, exhibiting excellent physicochemical indices and sensory attributes. The antioxidant efficacy of the fermented Suaeda tea persists significantly throughout a 180-day duration. The optimization of the fermentation process for Suaeda tea not only provides a theoretical framework for large-scale production but also establishes a foundation for Suaeda salsa in the tea beverage sector. This innovation enriches the market with a diverse range of health-promoting teas, catering to the growing consumer demand for nutritious and beneficial beverages.