Orange

Genus Citrus

One tree gives three completely different oils, depending on which part you use. The peel, pressed cold, is almost pure limonene and smells like the fruit itself. The blossom gives neroli, delicate and deeply floral, and the leaves and twigs give petitgrain, green and woody in between. In animal studies, repeated doses of bitter orange oil eased anxious behaviour by acting on a serotonin receptor.^[1] In a trial of children having dental treatment, orange oil in the air lowered both their saliva cortisol and their pulse.^[2]

Sweet Orange

Citrus sinensis

Also Known As: Orange, Sweet Orange Peel
Family: Citrus
Perfumery Note: Top
Intensity: Medium
Extraction: Cold Pressed
Plant Parts: Fruit peel
Origins: Brazil, United States, Italy
Effect: Energy & Uplifting
Aroma: Citrus, Sweet, Fruity
Applications: Diffusing & Inhalation, Perfumery & Fragrance Making, Cooking & Flavouring, Household & Cleaning
Price: $$$$The most produced essential oil in the world; a massive byproduct of the juice industry

Sweet orange oil is squeezed from the peel, which is why it smells exactly like scratching a fresh orange. Nine tenths of it is limonene, the compound behind that bright, round sweetness. In animal studies, breathing it in reversed low-mood behaviour and calmed an overactive stress response.^[3] In a controlled study in people, volunteers who smelled it before a stressful task showed no rise in anxiety, tension or heart rate.^[4]

Neroli

Citrus aurantium var. amara

Also Known As: Orange Blossom, Bitter Orange Flower
Family: Floral
Perfumery Note: Middle
Intensity: Medium
Extraction: Steam Distillation
Plant Parts: Blossoms
Origins: Tunisia, Morocco, France
Effect: Sleep & Relaxation, Romance & Mood
Aroma: Floral, Citrus, Fresh
Applications: Diffusing & Inhalation, Skincare, Perfumery & Fragrance Making
Price: $$$$Steam-distilled from hand-picked orange blossoms; thousands of petals produce only a tiny drop of oil

Neroli is distilled from bitter orange blossom, and it takes a great many flowers to fill a small bottle. It smells green, honeyed and unmistakably floral, softened by indole, the same compound that gives jasmine its animal warmth. Few oils have better human evidence for calming nerves. In a trial of 140 heart patients, breathing it in lowered anxiety more than a dummy scent.^[5] In a trial of women in labour, it lowered anxiety at every stage measured.^[6]

Petitgrain

Citrus aurantium var. amara

Also Known As: Petitgrain Bigarade, Bitter Orange Leaf
Family: Citrus
Perfumery Note: Top
Intensity: Medium
Extraction: Steam Distillation
Plant Parts: Leaves, Twigs
Origins: Paraguay, France, Tunisia
Effect: Grounding & Centering, Sleep & Relaxation
Aroma: Citrus, Woody, Herbaceous
Applications: Diffusing & Inhalation, Skincare, Perfumery & Fragrance Making
Price: $$$$Distilled from mandarin tree leaves; distinct from the peel oil

Petitgrain comes from the leaves and twigs of the same tree that gives neroli and bitter orange. It sits between them, green and woody with the orange still recognisable underneath. Around half the oil is linalyl acetate, the compound that makes lavender smell calm rather than sharp. In a controlled study, university staff who inhaled it worked better, which the researchers put down to a steadying effect on the nervous system.^[7] The leaves are richest in that compound in autumn, and the oil also protects cells from damage.^[8]

Bitter Orange

Citrus aurantium var. amara

Also Known As: Seville Orange, Sour Orange
Family: Citrus
Perfumery Note: Top
Intensity: Medium
Extraction: Cold Pressed
Plant Parts: Fruit peel
Origins: Italy, Spain, Tunisia
Effect: Sleep & Relaxation, Focus & Mental Clarity, Energy & Uplifting
Aroma: Citrus, Bitter, Fresh
Applications: Diffusing & Inhalation, Perfumery & Fragrance Making, Cooking & Flavouring
Price: $$$$Peel is a byproduct of bitter orange processing for food and liqueur industries; lower demand compared to sweet orange keeps the price modest

Bitter orange oil is pressed from the rind of the fruit that makes marmalade. Like sweet orange it is mostly limonene, but traces of heavier compounds add a resinous, bitter edge. It is the only one of the three bitter orange oils studied for the stomach. In rats with induced ulcers, the oil healed 44% and pure limonene 56%, by growing new blood vessels and thickening the protective mucus.^[9] Testing also finds it protects cells and slows enzymes tied to Alzheimer's and diabetes.^[10]

Blood Orange

Citrus sinensis

Also Known As: Moro Orange, Tarocco Orange, Sanguinello, Pigmented Orange
Family: Citrus
Perfumery Note: Top
Intensity: Medium
Extraction: Cold Pressed
Plant Parts: Fruit peel
Origins: Italy, Spain, United States
Effect: Energy & Uplifting, Sleep & Relaxation
Aroma: Citrus, Sweet, Berry-like
Applications: Diffusing & Inhalation, Perfumery & Fragrance Making, Cooking & Flavouring
Price: $$$$A cold-pressed byproduct of the pigmented orange juice industry, similar in cost structure to sweet orange but produced in smaller regional volumes

Blood orange oil is pressed from red-fleshed varieties like Moro and Tarocco. It is mostly limonene, like ordinary sweet orange, but a trace of beta-damascenone adds the faint berry edge. The red does not come through: the pigments that colour the flesh dissolve in water, not oil, so the oil is the usual orange gold. In lab tests the oil and limonene calmed inflammation, protected cells from damage and slowed enzymes that act on skin.^[11]

Essential Nose

Orange

Sweet Orange

Neroli

Petitgrain

Bitter Orange

Blood Orange

References