Influence of different lactic acid bacteria strains and milling process on the solid-state fermented green and red lentils (Lens culinaris L.) properties including gamma-aminobutyric acid formation

Abstract

The aim of this study was to evaluate the influence of lactic acid bacteria (LAB) strains (Lactiplantibacillus plantarum No.122 and Lacticaseibacillus casei No.210) and milling process on the solid-state fermented (for 24 h, at 30°C) green and red lentils (Lens culinaris L.) properties, chiefly pH, LAB viable counts, color coordinates, free amino acid (FAA) profile, γ-aminobutyric acid (GABA) and biogenic amine (BA) concentrations, fatty acid (FA) and volatile compound (VC) profiles. Results showed that both of the tested LAB strains are suitable for the fermentation of lentils: pH of fermented lentils was <4.5 and LAB viable counts >8.0 log10 colony-forming units (CFU)/g. A very strong negative correlation was found (r = −0.973, p ≤ 0.0001) between LAB counts and pH of the samples. Also, fermentation and milling process were significant factors toward color coordinates of the lentils. In most of the cases, solid-state fermentation (SSF) increased essential FAA content in lentils; however, some of the non-essential FAA content was reduced. SSF significantly increased GABA concentration in lentils and milling process was a significant factor on GABA content of the samples (p ≤ 0.05). The main BA in lentils was spermidine, and SSF decreased their total BA content (34.8% on average in red lentils and 39.9% on average in green lentils). The main FA in lentils were linoleic and oleic. The main VC in lentils were hexanal, 1-hexanol, hexanoic acid, D-limonene and (E)-2-nonen-1-ol. Furthermore, most of the VC showed significant correlations with pH of lentil samples, LAB counts and FA content. Finally, the LAB strain used for fermentation and the milling process of lentils are significant factors for most of the analyzed parameters in lentil. Moreover, despite the higher GABA concentration found in green non-milled SSF lentils, application of combined milling and SSF is recommended because they showed the lowest BA content in addition to higher essential FAA and GABA concentrations.

Submerged fermentation of lentil protein isolate and its impact on protein functionality, nutrition, and volatile profiles

“…The next abundant peak at ∼5.6 min was hexanal, followed by nonanal at ∼12.8 min. Hexanal provides a green, fatty, leafy, vegetative, fruity, and clean flavor with a woody nuance (Mockus et al, 2023), and nonanal has a strong fruity or floral odor (Kim et al, 2019). Although toluene and hexanal were still present in all samples, their peak area was reduced after fermentation (Supporting Information section).…”

“…Some of these newly formed compounds were identified as acetic acid, propanoic acid, 2-methyl propanoic acid, butanoic acid, 2-methyl butanoic acid, 3-methyl butanoic acid, hexanoic acid, butanoic acid pentyl ester, and butanoic acid hexyl ester. New volatile compound formation in LAB-fermented red and green lentils was reported to include acetic acid, hexanoic acid, pantolactone, (E)-non-2-enal, (E)-2-nonen-1-ol, (2E,4E)nona-2,4-dienal, and 2-undecenal in Mockus et al (2023); the complexity and intensity of the volatile profiles differed significantly among lentil cultivars. The present finding indicates that SmF was able to modify the volatile profile of LPI by introducing new compounds.…”

Changes in Chemical Composition of Lentils, Including Gamma-Aminobutyric Acid and Volatile Compound Formation during Submerged and Solid-State Fermentation with Pediococcus acidilactici

“…The fermentation of various matrices can be performed under submerged (SMF) and solid-state fermentation (SSF) conditions [16,17]. On one hand, SMF is defined as a type of process wherein the anaerobic or partially anaerobic fermentation of a substrate is performed in the presence of free water, also known as a liquid medium [18].…”

Effect of Growth Stages and Lactic Acid Fermentation on Anti-Nutrients and Nutritional Attributes of Spinach (Spinacia oleracea)

“…In recent years, fermentation technologies based on the inoculation of various probiotic bacteria like Lactiplantibacillus plantarum (Lp. Plantarum) have played an important role in lowering antinutritional factors and increasing the nutritional profiles of fermented goods [ 12 , 13 , 14 , 15 , 16 ]. However, data on the application of microbial strain (starter cultures) like Lp.…”