lactic fermentation of bitter gourd
process / process-bitter-gourd-lactic-fermentation
ニガウリの乳酸発酵
Lactic fermentation of bitter gourd is an experimental process fermenting bitter-gourd juice with Lactobacillus plantarum.
On this page (7 sections)
Reading the bitterness
In an experiment fermenting bitter-gourd (Momordica charantia) juice with Lactobacillus plantarum, sensory comparisons were made across conditions varying in time, temperature, and inoculum size. A significant difference in bitterness between unfermented and fermented samples was reported, and many panelists perceived reduced bitterness in the fermented samples.
Another study compared fresh samples, unfermented pressed juice (NFJ), and fermented pressed juice (FJ) in 3 groups using an electronic-tongue bitterness sensor (SCS), after inoculating with Lactiplantibacillus plantarum strain dy-1 and fermenting at 31°C for 24 hours. The bitterness response was reported as "Fresh had the highest bitter taste response value, followed by NFJ, and FJ had the least bitter response value".
Both studies point in the same direction: lactic fermentation reduces bitterness in bitter-gourd juice. However, they provide independent confirmation under different measurement methods and bacterial strains, one a sensory evaluation with a small panel and the other an electronic-tongue sensor. Their findings cannot be directly generalized to pickles or solid ingredients.
Changes were also observed in chemical composition. Using the same dy-1 strain, a comparison by UPLC-Q-TOF-MS/MS of saponin compositions in 3 forms—fresh-pressed (FBMS), unfermented juice (NFBMS), and fermented juice (FJBMS)—found significantly lower levels of momordicine I and II, the bitter triterpenoids considered to contribute most to bitterness, in fermented than unfermented juice. Meanwhile, momordicine U, the deglycosylated precursor of momordicine I, increased more than 2-fold with fermentation. Exact absolute contents were not provided; the description is limited to relative differences from VIP-plot analysis.
Sources for this overview
Checked for this overview: Used the significant difference in bitterness against the unfermented control and panelists’ perceptions. / Used the limitation that the panel was small and the results cannot be generalized.
Checked for this overview: Used the electronic-tongue comparison of bitterness responses among 3 groups: fresh, NFJ, and FJ. / Used the fact that the independent confirmation involved different measurement methods and bacterial-strain conditions. / Decrease in momordicine I and II and increase in momordicine U during fermentation.
Follow the connections
lactic fermentation of bitter gourd →reduces→ momordicine I
Hypotheses and recipe candidates for this entry are on the Japanese page.
Structured claims — open a section to read each claim's confidence, evidence and limits
Sensory (1)
Scope: A sensory comparison varying L. plantarum fermentation time, temperature, and inoculation rate
Note: The majority of panelists perceived reduced bitterness compared with the unfermented control. Not to be generalized to all fermented foods.
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process-bitter-gourd-lactic-fermentation —reduces_perceived_bitterness_of→ "Bitter gourd juice"How processing and cooking change it (1)
Scope: Layer: food. A comparison of saponin composition among fresh-pressed (FBMS), non-fermented (NFBMS), and dy-1-fermented (FJBMS) juice, by VIP-plot analysis on UPLC-Q-TOF-MS/MS.
Show data
process-bitter-gourd-lactic-fermentation —reduces→ compound-momordicine-i