Location: Food Science ResearchTitle: Characterization of robust Lactobacillus plantarum and Lactobacillus pentosus starter cultures for environmentally friendly low-salt cucumber fermentations
|ANEKELLA, KARTHEEK - North Carolina State University|
|Perez Diaz, Ilenys|
Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/21/2020
Publication Date: 10/1/2020
Citation: Anekella, K., Perez Diaz, I.M. 2020. Characterization of robust Lactobacillus plantarum and Lactobacillus pentosus starter cultures for environmentally friendly low-salt cucumber fermentations. Journal of Food Science. 85(10):3487-3467. https://doi.org/10.1111/1750-3841.15416.
Interpretive Summary: With the adoption of sodium chloride free cucumber fermentation, it is necessary to identify suitable starter cultures that can quickly convert the sugars naturally present in the fruits to lactic acid with a concomitant drop in pH and inhibition of undesired microbes. This study focused on the physiological characterization of eight bacteria that can serve as starter cultures for low-salt cucumber fermentations. The findings suggest that the cultures scrutinized here can provide for metabolic versatility, boost the progress of a fermentation under stress conditions for microbial growth and persistence, and augment the safety and microbial stability of the bioconversion. This research enables the design of robust and autochthonous starter cultures for commercial-low-salt cucumber fermentations.
Technical Abstract: Seven candidates for starter cultures for cucumber fermentations belonging to the Lactobacillus pentosus and Lactobacillus plantarum species were characterized based on physiological features desired for pickling.The isolates presented variable carbohydrate utilization profile on API® 50CHL test strips.The L. pentosus strains were unable to utilize '-xylose in MRS broth or the M medium. The lactobacilli were unable to produce histamine, tyramine, putrescine, and cadaverine in biogenic amine broth containing the necessary precursors. Production of '-lactic acid by the lactobacilli, detected enzymatically, was stimulated by growth in MRS broth as compared to cucumber juice medium (CJM). The lactobacilli utilized malic acid in the malate decarboxylase medium.Exopolyssacharide biosynthesis related genes were amplified from the lactobacilli. A sugar type-dependent-ropy phenotype was apparent for all the cultures tested in MRS and CJM. The genes associated with bacteriocin production were detected in the lactobacilli, but not the respective phenotypes. The antibiotic susceptibility profile of the lactobacilli mimics that of other L. plantarum starter cultures. It is concluded that the lactobacilli strains studied here are suitable starter cultures for cucumber fermentation.