The effects of ropy exopolysaccharide-producing Lactiplantibacillus plantarum strains on tarhana quality

Abstract

Tarhana, a traditional fermented food, is one of the earliest instant soups, consumed for centuries by the Anatolians and used as infant nutrition due to its high cereal, vegetable and dairy content. Improving tarhana's desired consistency and health-promoting properties while maintaining its functionality may expand the consumption of this traditional food. The aim of this study is to use recently characterised, EPS-producing Lactiplantibacillus plantarum strains to produce functional tarhana with improved technological properties. Ropy EPS-producing L. plantarum strains were able to grow and produce EPS during the fermentation of tarhana, which enabled the production of tarhana samples with acceptable quality. EPS-producing L. plantarum strains showed a greater than 2-fold higher consistency index than tarhana samples fermented without EPS L. plantarum strains. EPS produced by L. plantarum strains maintained the desired reddish colour of tarhana powders during 90 days of storage. Sensory analysis scores were highest for the two tarhana samples fermented with L. plantarum PFC309 + PFC310 and PFC310 + PFC311. In conclusion, it was determined that ropy EPSs produced by L. plantarum strains effectively maintained the desired red colour of tarhana and improved the viscosity of tarhana soups. Additionally, L. plantarum PFC309 and PFC311 strains are potential starter cultures able to produce and improve the functionality of tarhana with respect to technological and health aspects.