bitter orange peel
ingredient / ingredient-bitter-orange-peel
ビターオレンジ果皮（ダイダイ果皮） / Citrus aurantium L.
Bitter orange peel is the peel of bitter orange (daidai). It contains bitter flavanone glycosides, neohesperidin and naringin, and is used as a bittering ingredient in bitters, liqueurs, and marmalade.
On this page (8 sections)
Reading the bitterness
The peel of bitter orange (daidai, Citrus aurantium) contains the bitter flavanone glycosides neohesperidin and naringin. Naringin is also known as a glycoside responsible for grapefruit bitterness. In HPLC quantification of leaves, flower buds, and fruit of C. aurantium, neohesperidin concentrations exceeded naringin in every organ examined, and this was also reported for fruit. This is compositional quantification, not sensory confirmation of bitterness intensity, so its connection to bitterness perception remains unconfirmed.
The same study recorded differences by organ and developmental stage. The neohesperidin/naringin ratio in fruit rose to 3.15 during the 3–7 mm diameter young-fruit stage, then fell sharply to 1.13 at 35 mm and to 1.02 at maturity (61 mm diameter, about 200 days after flowering). In flower buds, the stigma had the highest ratio, 3.83, among 6 parts—receptacle, ovary, stigma, petals, filaments, and anthers—and the ovary also had high concentrations. Petals had a low ratio but accounted for 42.34% of the total flower weight, so their contribution is described as large. These data show chemical-composition changes within organs and alone cannot establish changes in bitterness intensity.
Naringinase treatment hydrolyzes naringin first through α-L-rhamnosidase into rhamnose and prunin, then through β-D-glucosidase into glucose and tasteless naringenin. This pathway was organized in a 2025 systematic review of naringin deglycosylation in citrus. The review also cites a value that prunin bitterness is about 70% lower than naringin, but that value comes from a prior study cited by the review.
Sources for this overview
Checked for this overview: Quantification of 2 bitter glycosides by organ and developmental stage. / Neohesperidin concentration data by flower-bud part. / Used the numerical data showing a non-monotonic ratio across fruit developmental stages as the basis for this paragraph.
Checked for this overview: The two-step hydrolysis pathway by naringinase and the bitterness-reduction pathway.
Other names: Citrus aurantium L. (la)
Follow the connections
bitter orange peel →contains→ neohesperidin
Structured claims — open a section to read each claim's confidence, evidence and limits
Composition and content (1)
Scope: Quantification of C. aurantium by organ and developmental stage (fruit including the peel)
Show data
ingredient-bitter-orange-peel —contains→ compound-neohesperidinHow processing and cooking change it (1)
Scope: Layer: Literature. A PRISMA-compliant systematic review on naringinase application and citrus flavonoid deglycosylation. This is a cross-study synthesis of prior work on debittering naringin in citrus fruits, including grapefruit, pomelo, bitter orange, and kinnow, rather than a primary experiment on bitter-orange peel itself.
Show data
ingredient-bitter-orange-peel —can_be_debittered_by→ "Enzymatic treatment with naringinase. Naringin is first hydrolyzed by α-L-rhamnosidase into rhamnose and prunin, then prunin is hydrolyzed by β-D-glucosidase into glucose and tasteless naringenin."