Citrus extract

Description

• Preparation obtained from peels, pulp, and/or seeds of Citrus spp. (e.g., Citrus limon, C. sinensis, C. aurantium, C. paradisi, C. bergamia), available as hydroalcoholic, glyceric/glycolic, or spray-dried standardized forms.

• Primary roles: natural flavoring and, in specific fractions, mild antioxidant/color contributor; also used as a functional extract in foods, beverages, and cosmetics.

• Sensory profile: bright citrus (lemon/orange/grapefruit), floral, and bitter nuances (e.g., naringin in grapefruit).

Caloric value (per 100 g)

• Hydroalcoholic extract: ~20–120 kcal/100 g (depends on solids and residual ethanol).

• Glyceric/glycolic extract: ~150–300 kcal/100 g.

• Dry extract (powder): ~200–380 kcal/100 g.

• At typical usage levels, the energy contribution is modest.

Key constituents

• Flavonoids: hesperidin, naringin, eriocitrin, diosmin (species-dependent).

• Organic acids: chiefly citric and malic acids (impact pH and perceived freshness).

• Terpenoids (traces of essential-oil components): limonene, linalool, citral; may be de-terpenated depending on process.

• Limonoids: limonin, nomilin (bitterness contributors).

• Pectins/polysaccharides and variable vitamin C (often reduced in extracts).

• Typical markers: TPC (total phenolic content), HPLC flavonoid profile (e.g., hesperidin/naringin), °Brix, pH; for lime/bergamot, monitor furocoumarins.

Production process

• Raw materials: selected peels/pulp (often upcycled from juice processing).

• Extraction: water/ethanol at controlled pH or glycerin/glycols; optional ion-exchange/membranes to enrich flavonoids or for de-bittering (e.g., naringinase/resins).

• Clarification and low-temperature concentration; standardization to flavonoids/°Brix; controls for pesticides/metals and microbiology.

• Packaging: light/oxygen-barrier containers under GMP/HACCP.

Sensory and technological properties

• Aroma/acidity: delivers fresh, zesty notes; bitterness increases with naringin/limonin.

• Color: pale yellow to amber (concentrates); stability depends on pH and oxygen.

• Compatibility: may cause haze in beverages (pectins/oils); possible protein complexation → precipitates.

Food uses

• Beverages (soft drinks, hard seltzers, teas), syrups, confectionery, bakery, dairy/plant drinks, sauces/toppings, and marinades.

• Peel-derived fractions for flavor/color. Typical inclusion 0.02–0.30%, to be tuned by pilot trials to reach sensory targets.

Nutrition and health

• Supplies flavonoids with in-vitro antioxidant activity; avoid unauthorized health claims.

• Grapefruit (C. paradisi): furocoumarins can interact with medications (e.g., CYP3A4 inhibition) → use caution if used at meaningful levels.

• Sulfites are not intrinsic but may appear from certain supply chains (label if present).

Lipid profile

• Fat is negligible; SFA, MUFA, PUFA occur only in traces (residual essential-oil components) with no meaningful nutritional impact at use levels.

Quality and specifications (typical topics)

• TPC, flavonoid markers (e.g., hesperidin/naringin by HPLC), °Brix, pH, color (Lab*), residual limonene.

• Furocoumarins (e.g., bergapten) for lime/bergamot; pesticides/metals within limits.

• Microbiology per dosage form; residual ethanol for hydroalcoholic grades.

• Sensory: clean profile, free of oxidized/terpenic off-notes.

Storage and shelf-life

• Store cool, dark, in tightly closed containers; minimize dissolved O₂ in solutions.

• Powders: control RH/aw to limit caking and browning; apply FIFO.

• Indicative shelf-life 12–24 months when in spec.

Allergens and safety

• Citrus is not a major EU allergen; oxidized limonene/linalool can cause contact reactions in sensitive individuals.

• Phototoxicity: bergamot/lime fractions may contain furocoumarins → for cosmetics prefer FCF (furocoumarin-free) grades and observe IFRA limits.

• Check local labeling requirements (e.g., sulfites/ethanol if present).

INCI functions in cosmetics

• Typical listings: Citrus Limon (Lemon) Peel Extract, Citrus Aurantium Dulcis (Orange) Peel Extract, Citrus Paradisi (Grapefruit) Fruit Extract, Citrus Aurantium Amara (Bitter Orange) Peel Extract, Citrus Bergamia (Bergamot) Fruit Extract.

• Roles: antioxidant, skin conditioning, masking/fragrance; for leave-on uses, comply with IFRA and prefer FCF grades.

Troubleshooting

• Haze/precipitates in beverages: pectins/essential oils → clarify/filter, emulsify, or use de-terpenated grades.

• Excess bitterness: high naringin/limonin → select de-bittered processes/cultivars, reduce dose, adjust pH/sugars.

• Discoloration/oxidation: light/O₂ → barrier packaging, mild chelators, permitted antioxidants.

• Lot variability: botanical origin/process differences → standardize to HPLC/TPC markers with tight specs.

Sustainability and supply chain

• Upcycling of juice-industry peels reduces waste and enables energy recovery.

• Manage effluents toward BOD/COD targets; recyclable packaging; supplier audits and traceability under GMP/HACCP.

Conclusion
Citrus extract combines fresh aroma, acidity, and phenolic functionality. Performance depends on species/plant part, management of bitterness/haze, and rigorous standardization—with these controls it delivers stable, repeatable results in beverages, sweets, and cosmetics.

Mini-glossary

• TPC — Total phenolic content: overall phenolics; a proxy for polyphenolic fraction.

• HPLC — High-performance liquid chromatography: profiles flavonoids (e.g., hesperidin/naringin) and identity markers.

• FCF — Furocoumarin-free: grade controlled for furocoumarins to reduce phototoxicity.

• IFRA — International Fragrance Association: safety standards/limits for fragrance ingredients.

• SFA — Saturated fatty acids: excess may raise LDL; here only traces.

• MUFA — Monounsaturated fatty acids (e.g., oleic): generally neutral/favorable; trace here.

• PUFA — Polyunsaturated fatty acids (n-6/n-3): beneficial when balanced; trace here.

• GMP/HACCP — Good Manufacturing Practice / Hazard Analysis and Critical Control Points: hygiene and preventive-safety frameworks with defined CCP.

• BOD/COD — Biochemical/Chemical oxygen demand: indicators of wastewater organic load.

• FIFO — First in, first out: inventory rotation using older lots first.

Extraction and antioxidant activity

The current method used in most countries for the production of cold-pressed orange oil is the simultaneous extraction of an emulsion of juice and oil from the whole fruit. Cold pressed orange oil contains waxes, pesticide residues and carotenoids (1). The current method used in most countries for manufacturing cold-pressed orange oil is simultaneous extraction of a juice and oil emulsion from the whole fruit. Cold-Pressed orange oil contains waxes, pesticide residues and carotenoids. For this reason it would be appropriate to adopt a molecular distillation method to remove them as this oil can be used in the clinical treatment of patients with malignant brain tumors (2), to inhibit angiogenesis, metastasis and cell death in human colon cancer cells (3).

In this study, the orange peel of 12 cultivars of Citrus sinensis from central-eastern Sicily was employed to obtain essential oils and extracts. The ones were extracted through steam distillation, the others through extraction in hexane. Chemical constituents were evaluated in terms of qualitative and quantitative analyses by gas chromatography/mass spectrometry. Fifty-four components were identified in the steam essential oils and 44 in the extracts. In all the cultivars, the main component is d-limonene (73.9-97%); discrete percentages of linalool, geraniol and nerol were also found. Cluster analysis based on essential oils composition showed a certain degree of affinity between cultivars of the same type. The antimicrobial activity was investigated against three micro-organisms (Staphylococcus aureus, Listeria monocytogens and Pseudomonas aeruginosa). 'Sanguinello' and 'Solarino Moro' essential oils are significantly active against L. monocytogenes, while 'Valencia' hexanic extract against all the tested micro-organisms(4).

Acute otitis media (AOM) animal model was built and diet containing orange peel essential oil microcapsules were administrated to AOM animals. Pharmacological test showed that orange peel essential oil treatment could decrease serum and cochlea malondialdehyde (MDA), immunoglobulins A (IgA), immunoglobulins G (IgG), immunoglobulins M (IgM) levels and increase antioxidant enzymes activities. It can be concluded that orange peel essential oil treatment could decrease oxidative injury in acute otitis media rats.

Typical chemical composition of an orange essential oil

Twenty four compounds, accounting for 97.9% of the total oil, were identified based on their mass spectra. The main components were terpenic molecules, and the oil was composed of 97.3% monoterpenes (which include 19.0% oxygenated monoterpenes) and 0.5% sesquiterpenes. The main constituents were limonene (74.6%), limonene 1,2-epoxide (3.5%), cis-p-mentha-2,8-dien-1-ol (3.2%) and (E)-carveol (2.4%) (6). 

CAS: 8008-57-9 Orange peel oil

Orange studies

References________________________________________________________________________

(1) Yang C, Chen H, Chen H, Zhong B, Luo X, Chun J. Antioxidant and Anticancer Activities of Essential Oil from Gannan Navel Orange Peel. Molecules. 2017 Aug 22;22(8):1391. doi: 10.3390/molecules22081391. 

Abstract. China is one of the leading producers of citrus in the world. Gannan in Jiangxi Province is the top navel orange producing area in China. In the present study, an essential oil was prepared by cold pressing of Gannan navel orange peel followed by molecular distillation. Its chemical composition was analyzed by GC-MS. Twenty four constituents were identified, representing 97.9% of the total oil. The predominant constituent was limonene (74.6%). The anticancer activities of this orange essential oil, as well as some of its major constituents, were investigated by MTT assay. This essential oil showed a positive effect on the inhibition of the proliferation of a human lung cancer cell line A549 and prostate cancer cell line 22RV-1. Some of the oil constituents displayed high anticancer potential and deserve further study.

(2) Chen TC, Fonseca CO, Schönthal AH. Preclinical development and clinical use of perillyl alcohol for chemoprevention and cancer therapy. Am J Cancer Res. 2015 Apr 15;5(5):1580-93.

Abstract. Perillyl alcohol (POH) is a naturally occurring dietary monoterpene isolated from the essential oils of lavender, peppermint, and other plants. Medical interest in this compound was generated by research findings showing that POH was able to inhibit the growth of tumor cells in cell culture and exert cancer preventive and therapeutic activity in a variety of animal tumor models. Based on this promising preclinical work, POH was formulated in soft gelatine capsules and orally administered to cancer patients several times a day on a continuous basis. However, such clinical trials in humans yielded disappointing results, also because the large number of capsules that had to be swallowed caused hard-to-tolerate intestinal side effects, causing many patients to withdraw from treatment due to unrelenting nausea, fatigue, and vomiting. As a result, efforts to treat cancer patients with oral POH were abandoned and did not enter clinical practice. Intriguingly, clinical trials in Brazil have explored intranasal POH delivery as an alternative to circumvent the toxic limitations of oral administration. In these trials, patients with recurrent malignant gliomas were given comparatively small doses of POH via simple inhalation through the nose. Results from these studies show this type of long-term, daily chemotherapy to be well tolerated and effective. In this review, we will present the vicissitudes of POH's evaluation as an anticancer agent, and its most recent success in therapy of patients with malignant brain tumors.

(3) Chidambara Murthy KN, Jayaprakasha GK, Patil BS. D-limonene rich volatile oil from blood oranges inhibits angiogenesis, metastasis and cell death in human colon cancer cells. Life Sci. 2012 Oct 5;91(11-12):429-439. doi: 10.1016/j.lfs.2012.08.016. Epub 2012 Aug 20. PMID: 22935404.

(4)  Geraci A, Di Stefano V, Di Martino E, Schillaci D, Schicchi R. Essential oil components of orange peels and antimicrobial activity.  Nat Prod Res. 2017 Mar;31(6):653-659. doi: 10.1080/14786419.2016.1219860. 

Abstract. In this study, the orange peel of 12 cultivars of Citrus sinensis from central-eastern Sicily was employed to obtain essential oils and extracts. The ones were extracted through steam distillation, the others through extraction in hexane. Chemical constituents were evaluated in terms of qualitative and quantitative analyses by gas chromatography/mass spectrometry. Fifty-four components were identified in the steam essential oils and 44 in the extracts. In all the cultivars, the main component is d-limonene (73.9-97%); discrete percentages of linalool, geraniol and nerol were also found. Cluster analysis based on essential oils composition showed a certain degree of affinity between cultivars of the same type. The antimicrobial activity was investigated against three micro-organisms (Staphylococcus aureus, Listeria monocytogens and Pseudomonas aeruginosa). 'Sanguinello' and 'Solarino Moro' essential oils are significantly active against L. monocytogenes, while 'Valencia' hexanic extract against all the tested micro-organisms.

(5)  Lv YX, Zhao SP, Zhang JY, Zhang H, Xie ZH, Cai GM, Jiang WH. Effect of orange peel essential oil on oxidative stress in AOM animals.  Int J Biol Macromol. 2012 May 1;50(4):1144-50. doi: 10.1016/j.ijbiomac.2012.02.002. Epub 2012 Feb 10.

(6)  Yang C, Chen H, Chen H, Zhong B, Luo X, Chun J. Antioxidant and Anticancer Activities of Essential Oil from Gannan Navel Orange Peel.   Molecules. 2017 Aug 22;22(8). pii: E1391. doi: 10.3390/molecules22081391.

 Abstract.China is one of the leading producers of citrus in the world. Gannan in Jiangxi Province is the top navel orange producing area in China. In the present study, an essential oil was prepared by cold pressing of Gannan navel orange peel followed by molecular distillation. Its chemical composition was analyzed by GC-MS. Twenty four constituents were identified, representing 97.9% of the total oil. The predominant constituent was limonene (74.6%). The anticancer activities of this orange essential oil, as well as some of its major constituents, were investigated by MTT assay. This essential oil showed a positive effect on the inhibition of the proliferation of a human lung cancer cell line A549 and prostate cancer cell line 22RV-1. Some of the oil constituents displayed high anticancer potential and deserve further study.