MICROBIOLOGICAL QUALITY AND IN VIVO TOXICITY OF KOMBUCHA BASED ON NON-CONVENTIONAL EDIBLE PLANTS (PANC)

Kombucha is an Asian beverage based on a sugared vegetable infusion fermented by a symbiotic colony of bacterial and yeast presents in a cellulosic floating matrix. Non-conventional edible plants (PANC) are edible species traditionally consumed or used therapeutically. Some of these plants are not yet part of normal diet of the general population, but they present great economic and nutritional potential. An example is wax mallow (Malvaviscus arboreus Cav.) widely cultivated throughout the country and is an option for the diversification of substrate for kombucha production. The aim of this study was to evaluate microbiology quality and in vivo toxicity of kombucha produced from green tea (Camellia sinensis) and wax mallow. The beverages were prepared from green tea and wax mallow infusions (0.5%, w/v), added with sucrose (5%, w/v), symbiotic culture (2.5%, w/v) and inoculated along with 1% (v/v) of the previously fermented liquid. The beverages were incubated at 25 ± 2 °C for 14 days. The hygienic-sanitary quality was evaluated by counting molds, coliforms, coagulase-positive staphylococci (CoPS) and detection of Salmonella spp. Toxicity was tested in an in vivo model of Galleria mellonella larvae, divided into 5 groups, with 10 larvae for each group: green tea (GTV); green tea kombucha (GTK); wax mallow tea (WMT); wax mallow kombucha (WMK); control with buffered saline solution (GC). Results for enumeration of molds, coliforms, and CoPS for all produced beverages were < 10 FCU/mL, < 0.3 MPN/mL and < 10 FCU/mL, respectively. Salmonella spp. was not detected in 25 mL for all beverages. After 10 days of experimentation the larvae survived and no melanization was detected, this is a common process during the immune response of these insects as a result of stress or infection. The beverages evaluated presented satisfactory hygienic-sanitary conditions and no toxicity in the model studied was verified.