Preparation of fermented sugar-soaked black soybean snacks (FSBSS) and characterization of their quality changes

Harnessing Fermented Soymilk Production by a Newly Isolated Pediococcus acidilactici F3 to Enhance Antioxidant Level with High Antimicrobial Activity against Food-Borne Pathogens during Co-Culture

In this study, a newly isolated Pediococcus acidilactici F3 was used as probiotic starter for producing fermented soymilk to enhance antioxidant properties with high antimicrobial activity against food-borne pathogens. The objectives of this study were to investigate optimized fermentation parameters of soymilk for enhancing antioxidant property by P. acidilactici F3 and to assess the dynamic antimicrobial activity of the fermented soymilk during co-culturing against candidate food-borne pathogens. Based on central composite design (CCD) methodology, the maximum predicted percentage of antioxidant activity was 78.9% DPPH inhibition. After model validation by a 2D contour plot, more suitable optimum parameters were adjusted to be 2% (v/v) inoculum and 2.5 g/L glucose incubated at 30 °C for 18 h. These parameters could provide the comparable maximum percentage of antioxidant activity at 74.5 ± 1.2% DPPH inhibition, which was up to a 23% increase compared to that of non-fermented soymilk. During 20 days of storage at 4 °C, antioxidant activities and viable cells of the fermented soymilk were stable while phenolic and organic contents were slightly increased. Interestingly, the fermented soymilk completely inhibited food-borne pathogens, Salmonella Typhimurium ATCC 13311, and Escherichia coli ATCC 25922 during the co-culture incubation. Results showed that the soymilk fermented by P. acidilactici F3 may be one of the alternative functional foods enriched in probiotics, and the antioxidation and antimicrobial activities may retain nutritional values and provide health benefits to consumers with high confidence.

Probiotic Properties of Pediococcus pentosaceus JBCC 106 and Its Lactic Acid Fermentation on Broccoli Juice

To understand the biological roles of Pediococcus pentosaceus strains as probiotics isolated from the traditional Korean fermented food, Jangajji, Pediococcus pentosaceus was selected based on its high cinnamoyl esterase (CE) and antioxidant activities. The acid and bile stability, intestinal adhesion, antagonistic activity against human pathogens, cholesterol-lowering effects, and immune system stimulation without inflammatory effects were evaluated. Nitric oxide (NO) levels were measured in co-culture with various bacterial stimulants. Fermentation ability was measured by using a broccoli matrix and the sulforaphane levels were measured. Resistance to acidic and bilious conditions and 8% adherence to Caco-2 cells were observed. Cholesterol levels were lowered by 51% by assimilation. Moreover, these strains exhibited immunomodulatory properties with induction of macrophage TNF-α and IL-6 and had microstatic effects on various pathogens. Co-culture with various bacterial stimulants resulted in increased NO production. Fermentation activity was increased with the strains, and higher sulforaphane levels were observed. Therefore, in the future, the applicability of the selected strain to broccoli matrix-based fermented functional foods should be confirmed.

Production of Functional Buttermilk and Soymilk Using Pediococcus acidilactici BD16 (alaD+)

Functional foods or drinks prepared using lactic acid bacteria (LAB) have recently gained considerable attention because they can offer additional nutritional and health benefits. The present study aimed to develop functional drinks by the fermentation of buttermilk and soymilk preparations using the Pediococcus acidilactici BD16 (alaD⁺) strain expressing the L-alanine dehydrogenase enzyme. LAB fermentation was carried out for 24 h and its impact on the physicochemical and quality attributes of the fermented drinks was evaluated. Levels of total antioxidants, phenolics, flavonoids, and especially L-alanine enhanced significantly after LAB fermentation. Further, GC-MS-based metabolomic fingerprinting was performed to identify the presence of bioactive metabolites such as 1,2-benzenedicarboxylic acid, 1-dodecene, 2-aminononadecane, 3-octadecene, 4-octen-3-one, acetic acid, azanonane, benzaldehyde, benzoic acid, chloroacetic acid, colchicine, heptadecanenitrile, hexadecanal, quercetin, and triacontane, which could be accountable for the improvement of organoleptic attributes and health benefits of the drinks. Meanwhile, the levels of certain undesirable metabolites such as 1-pentadecene, 2-bromopropionic acid, 8-heptadecene, formic acid, and propionic acid, which impart bitterness, rancidity, and unpleasant odor to the fermented drinks, were reduced considerably after LAB fermentation. This study is probably the first of its kind that highlights the application of P. acidilactici BD16 (alaD⁺) as a starter culture candidate for the production of functional buttermilk and soymilk.