The microbiota of fermented dairy products contributes to the safety, flavor, and organoleptic qualities of the products. Moreover, metabolites obtained from the fermentation process enhance the milk nutritive value and digestibility, whereas dairy microorganisms could be the perfect carriers for reseeding the gut microbiota. The structural food matrix of fermented milk facilitates the delivery of viable microorganisms to the intestinal tract. Fermented dairy products may be beneficial to human health by improving lactose intolerance symptoms and for the production of bioactive compounds such as vitamins, gamma-amino butyric acid, exopolysaccharides, and bioactive peptides, among others. Also, fermented dairy products contribute to the modulation of the gut microbiota and the prevention of infections, inflammation, and cardiometabolic diseases. Furthermore, fermented dairy products constitute the hallmark of probiotics supply in the food market., This work was supported by the Spanish Ministry (Project AGL2016-75951-R), CDTI (INDEKA IDI-20190077) and CYTED (Project P917PTE0537/PCIN-2017-075)., Peer reviewed

This chapter covers methodologies currently in use for the selection and analysis of lactic acid bacteria (LAB) strains to be employed as starter cultures in dairy fermentations. The aspects covered are the methods for enumeration and identification of LAB strains and the evaluation of their technological properties for improving processing conditions and product quality during dairy fermentations. The selection of LAB strains based on health benefit properties and the conditions for the production and maintenance of dairy cultures are also addressed. The production of desirable and industrially robust dairy starter cultures can be achieved by choosing the desired phenotypic traits and the knowledge to select for these traits at the genotypic level. The analysis of a large number of strains for selecting specific properties requires high-throughput screening tests to progressively reduce the number of candidates. The advances in omics technologies and analytical instruments have provided the bases to improve the evaluation and selection of LAB strains that are able to restore the unique characteristics of traditional dairy products and to benefit human health., Financial support from Spanish Ministry of Science (Projects AGL2016-75951-R, PCIN-2017-075 and IDI-20190077) and CYTED (Strategic Project 917PTE0537) is acknowledged., Peer reviewed