Traditional fermented foods are among the richest sources of microorganisms, and some of these organisms display potential probiotic properties. Research on fermented foods for probiotic microorganisms remains scarce compared to other dairy products [48]. In recent years, plant-based fermented foods have been considered a potential medium for incorporating probiotic cultures via vegetable fermentation [22].

Food fermentation is one of the oldest food processing and preservation methods, which constitutes chemical changes in foods carried by enzymes, with these enzymes synthesized by living microorganisms [30]. Microbial fermentation is responsible for several favorable food characteristics, e.g. flavor, shelf-life and texture. Numerous classes of fermented vegetable products are available throughout the world [60]. However, their marketable distribution lags behind fermented meat and dairy products due to insufficiency of standardized manufacture protocols and dependency upon unpredictable weather and geographic conditions [13].

In India, plant-based food plays a role in everyday diet/consumption [12]. Several articles have postulated that plant-based fermented products are the “food of the future”. The combination of ancient food preservation methods such as salting and modern biotechnological tools may result in a controlled fermentation process [35].

koozh is a traditional south Indian porridge made from millet and consumed in fermented form in rural and urban Indian households. koozh is prepared from kezhvaragu (finger millet: Eleusine coracana), cumbu (Pearl millet: Pennisetum glaucum) and noyee (broken rice) in clay pots. gherkins/cucumbers (Cucumis sativus) are pickled by lacto-fermentation or immersion in acidic solution which renders a tart flavor [47].

Probiotics are defined as “live microorganisms which, when administrated in adequate amounts, confer a health benefit upon the host” [20]. Probiotics must fulfill certain basic criteria, i.e. tolerance to intestinal bile and pH concentration, susceptibility to antibiotics and inhibition of growth of other enteric pathogens. It is well established that probiotics confer numerous health benefits upon humans and animals, including antihypertensive, antimutagenic, hypocholesterolemic, anticarcinogenic, anti-osteoporosis and immune modulatory effects [3], [14].

In a previous work, we reported the cholesterol-reducing property of probiotic strains isolated from mother’s milk [3]. The aim of the current work is to isolate and characterize lactic acid bacteria (LAB) from traditional south Indian fermented koozh and fermented gherkin samples based on vital probiotic characteristics. Furthermore, functional properties were determined with the intention of selecting strains that effectively reduce cholesterol, exhibit aggregation properties and produce exopolysaccharide (EPS). The candidate fulfilling the established criteria might therefore potentially serve as a novel probiotic strain paving the way to intense research in medical applications.

(Source Elsevier Masson SAS)