Macadamia integrifolia seed oil: properties, uses, pros, cons, safety
Fixed oil obtained from the seeds/nuts of Macadamia integrifolia (family Proteaceae), used as an emollient and skin conditioning agent; in suitable grades, also used as an edible oil
Synonyms: macadamia seed oil; macadamia nut oil; refined macadamia oil; cold-pressed macadamia oil (grade-dependent)
INCI / functions: skin conditioning (emollient)
Definition
Macadamia integrifolia seed oil is a vegetable oil composed mainly of triglycerides with a distinctive lipid profile: beyond oleic acid, it often contains a relatively high share of palmitoleic acid (C16:1), a feature that contributes to a generally more silky and “gliding” skin feel than many common oils. Depending on cultivar, origin, and processing (refined vs cold-pressed), color, residual odor, and key parameters such as acid value and peroxide value vary, with impacts on stability and sensorial repeatability.
From a nutritional perspective (when intended for food use), it is an oil dominated by MUFA (monounsaturated fatty acids) and relatively low in PUFA (polyunsaturated fatty acids) compared with many vegetable oils; SFA (saturated fatty acids) are present but typically represent a smaller fraction. The lower PUFA fraction tends to support better oxidative stability, although initial raw material quality and storage conditions remain decisive.
Main uses
Food.
In food-grade quality, macadamia oil is used as an edible oil and lipid ingredient, often appreciated for a mild organoleptic profile and use as a seasoning oil or in culinary preparations. Suitability depends on quality specifications and compliance (limits on oxidation, contaminants, and identity parameters). Allergen management is relevant: macadamia is a tree nut and requires appropriate allergen-risk management and labeling in food applications.
Cosmetics.
In cosmetics it is mainly used as an emollient in creams, lotions, body oils, massage products, cleansing oils, and lip products. It is selected to improve spreading and comfort, reducing drag and supporting a soft after-feel without being excessively heavy. The meaningful palmitoleic content can contribute to a more “skin-affine” sensorial profile in certain leave-on products, making it attractive for nourishing and softening concepts.
In haircare it can be used in masks, pre-shampoo oils, and some leave-on products to increase shine and perceived softness. As with other oils, potential “weight” depends on dose, hair type, and overall formula architecture: on fine hair, lower levels or blends with lighter esters are often preferable.
Medicine.
Not a therapeutic active; it may appear as a vehicle/emollient in specific finished products.
Pharmaceutical.
May be used as a lipid excipient/vehicle in topical (and in specific contexts also oral) preparations when compliant with required specifications; in such cases, oxidation, acidity, and purity controls are essential.
Industrial use.
Use is primarily within personal care; other uses depend on technical specifications and grade availability.
Calories (energy value)
| Parameter | Value |
|---|
| Energy value | About 3700 kJ / 900 kcal per 100 g (oil: almost entirely lipids) |
Identification data and specifications
| Identifier | Value |
|---|
| INCI name | Macadamia Integrifolia Seed Oil |
| Origin | fixed oil from Macadamia integrifolia nuts/seeds (Proteaceae) |
| CAS number | 438545-25-6 and/or 159518-86-2 (common in SDS and databases); some sheets also list 129811-19-4 (alternative entry) |
| EC/EINECS number | variable by entry/supplier (examples in SDS: 273-313-5 or 605-184-1); verify against the purchased grade’s SDS/CoA |
| Physical state | liquid |
| Variability note | composition and parameters depend on cultivar, process, and grade (refined/cold-pressed) |
Chemical-physical properties (indicative)
| Property | Value | Note |
|---|
| Density (20–25 °C) | ~0.905–0.929 g/mL | typical range from specifications |
| Refractive index (20 °C) | ~1.466–1.470 | identity/quality indicator |
| Iodine value | ~65–87 g I₂/100 g | linked to degree of unsaturation |
| Saponification value | ~188–200 mg KOH/g | typical for triglyceride oils |
| Acid value | typically ≤4 mg KOH/g (spec) | hydrolysis/quality index |
| Peroxide value | often a limit ≤5–10 meq O₂/kg (spec) | primary oxidation indicator |
| Unsaponifiables | typically ~0.5–2% (spec) | grade-dependent |
Indicative lipid composition
| Fraction | Typical range | Note |
|---|
| Oleic acid (C18:1) | ~50–70% | often the dominant component |
| Palmitoleic acid (C16:1) | ~16–27% (sometimes higher) | key sensorial contributor |
| Palmitic acid (C16:0) | ~6–12% | saturated |
| Stearic acid (C18:0) | ~2–8% | saturated |
| Linoleic acid (C18:2) | ≤~6% | PUFA; influences oxidative stability |
| Linolenic acid (C18:3) | ≤~4% (often very low) | PUFA; more oxidation-prone |
| Arachidic acid (C20:0) | ≤~4% | saturated |
| Gadoleic acid (C20:1) | ≤~4% | monounsaturated |
Functional role and practical mechanism
| Function | What it does in formula | Technical note |
|---|
| Emollient | improves softness and skin comfort | surface lipid film |
| Skin conditioning | increases slip and reduces drag | useful in creams/lotions and body oils |
| Lipophilic carrier | solubilizes oil-soluble ingredients and fragrances | manage oxidative stability |
| Sensory modifier | provides a silky touch and “richness” | balance in ultra-light concepts |
Formulation compatibility
In O/W and W/O emulsions, macadamia oil is generally easy to incorporate and contributes a more silky touch; compatibility depends mainly on oil-phase design and emulsifier choice. For leave-on formulas, it is recommended to manage oxidative stability through: selecting low-PV lots, controlling exposure to light/heat/oxygen, and—if consistent with the project and regulatory context—using a suitable antioxidant strategy.
In anhydrous systems (body oils, massage oils, lip products), it can represent a substantial share of the oil phase. The most common issues relate to odor/color drift over time (oxidation) and sensorial lot-to-lot variability if specifications are not well defined (fatty acid profile, AV/PV, refractive index). In haircare, to limit build-up and weight, it is often used at moderate levels or blended with lighter esters.
For products aimed at acne-prone skin, evaluation should be done on the finished product: perceived oiliness depends on dose, total oil phase, sensorial polymers, and use pattern.
Use guidelines (indicative)
| Application | Typical range | Technical note |
|---|
| Face/body creams and lotions | 1–15% | adjust to sensorial target |
| Body and massage oils | 10–100% | verify PV/AV and fragrance stability |
| Lip products (sticks/balms) | 2–20% | wax synergy and oxidative stability |
| Hair masks/creams | 0.5–5% | softness and shine; watch build-up |
| Hair oil / pre-shampoo | 5–100% | adjust for fine hair and rinsability |
| Lightweight leave-on hair | 0.2–3% | often blended with lighter esters |
Quality, grades, and specifications
| QC parameter | What to check |
|---|
| Identity | INCI, CAS/EC alignment and documentation (SDS/CoA) |
| Acid value | hydrolysis index; impacts odor and stability |
| Peroxide value | primary oxidation; affects shelf life |
| Refractive index/density | lot-to-lot repeatability |
| Fatty acid profile | authenticity and sensorial consistency |
| Unsaponifiables | sensorial contribution; spec consistency |
| Contaminants | heavy metals, pesticides (if food-grade), process residues |
| Storage | control light/heat/oxygen exposure to limit oxidation |
Safety, regulatory, and environment
In cosmetics, safety is assessed on the finished product (use area, frequency, population). Macadamia oil is widely used as an emollient; however, sensitization can occur in predisposed individuals, and allergen management is particularly relevant in food applications and, as a precaution, also for leave-on products intended for sensitive consumers.
In manufacturing, applying GMP (Good manufacturing practice; benefit: reduces variability and contamination) improves control and repeatability. Where adopted as an approach, HACCP (Hazard analysis and critical control points; benefit: strengthens prevention and control at critical process points) supports preventive management of sensitive points.
Formulation troubleshooting
| Problem | Possible cause | Recommended intervention |
|---|
| Rancid odor / yellowing | oxidation (high PV, unsuitable storage) | select low-PV lots, manage air/light/heat exposure, evaluate a compatible antioxidant |
| Feel too “rich”/greasy | high level or combination with heavy lipids | reduce %, use lighter esters, optimize oil phase and texturizers |
| Emulsion instability | unsuitable emulsifier or unbalanced oil phase | retune HLB/emulsifier, adjust oil-phase structure, thermal stress testing |
| Cold haze | fraction crystallization, grade variability | select a more controlled grade, define cold test, optimize storage |
| Lot-to-lot sensorial variability | origin/process differences | set limits for fatty acid profile, RI/density, PV/AV; qualify suppliers |
Conclusion
Macadamia integrifolia seed oil is valued for a typically silky and comfortable sensorial profile, supported by a meaningful palmitoleic fraction. It is used as an emollient in many leave-on and anhydrous products, and it is versatile in haircare as well. Quality and formulation success depend critically on specifications (PV/AV, identity parameters, fatty acid profile) and rigorous management of oxidative stability across the supply chain and storage.
Mini-glossary
MUFA: monounsaturated fatty acids; health note: when replacing some saturated fats, they may support a more favorable dietary lipid profile within the overall diet.
PUFA: polyunsaturated fatty acids; health note: include essential fatty acids such as linoleic; more oxidation-prone, so oil stability is a technical focus.
SFA: saturated fatty acids; health note: excessive dietary intake is often associated with less favorable profiles; in vegetable oils they are often minor but relevant for texture.
Peroxide value (PV): indicator of primary oxidation in oils.
Acid value (AV): index of free fatty acids; linked to quality and hydrolysis.
GMP: Good manufacturing practice; benefit: reduces variability and contamination.
HACCP: Hazard analysis and critical control points; benefit: strengthens prevention and control at critical process points.
Studies
This oil contains moderate quantities of tocopherols and phenolic compounds and is quite similar to walnut oil for its antioxidant properties (1).
The seed oil in Macadamia integrifolia contains about 30% palmitoleic acid (16:1(Delta9)) (2).
References_____________________________________________________
(1) Shakerardekani A, Karim R, Ghazali HM, Chin NL. Textural, rheological and sensory properties and oxidative stability of nut spreads—a review. Int J Mol Sci. 2013 Feb 20;14(2):4223-41. doi: 10.3390/ijms14024223.
Abstract. Tree nuts are rich in macro and micronutrients, phytochemicals, tocopherols and phenolic compounds. The development of nut spreads would potentially increase the food uses of nuts and introduce consumers with a healthier, non-animal breakfast snack food. Nut spreads are spreadable products made from nuts that are ground into paste. Roasting and milling (particle size reduction) are two important stages for the production of nut spreads that affected the textural, rheological characteristic and overall quality of the nut spread. Textural, color, and flavor properties of nut spreads play a major role in consumer appeal, buying decisions and eventual consumption. Stability of nut spreads is influenced by its particle size. Proper combination of ingredients (nut paste, sweetener, vegetable oil and protein sources) is also required to ensure a stable nut spread product is produced. Most of the nut spreads behaved like a non-Newtonian pseudo-plastic fluid under yield stress which help the producers how to start pumping and stirring of the nut spreads. Similar to other high oil content products, nut spreads are susceptible to autoxidation. Their oxidation can be controlled by application of antioxidants, using processing techniques that minimize tocopherol and other natural antioxidant losses.
(2) Gummeson PO, Lenman M, Lee M, Singh S, Stymne S. Characterisation of acyl-ACP desaturases from Macadamia integrifolia Maiden & Betche and Nerium oleander L. Plant Sci. 2000 May 15;154(1):53-60. doi: 10.1016/s0168-9452(99)00268-x.
Abstract. The seed oil in Macadamia integrifolia contains about 30% palmitoleic acid (16:1(Delta9)) and Nerium oleander about 12% isoricinoleic acid (Delta9-hydroxy-18:1(Delta12)). It has been shown that palmitoleic acid can be produced by acyl-acyl carrier protein (ACP) desaturases and it has also been shown that fatty acid hydroxylation can occur via direct substitution of a hydrogen atom. Therefore it seemed possible that the enzymes responsible for the making of these unusual fatty acids in M. integrifolia and N. oleander were of acyl-ACP desaturase type. Extracts from developing M. integrifolia developing seeds showed a relative ratio of 16:0-ACP to 18:0-ACP desaturation that was about 13 times higher than in sunflower seeds. N. oleander seed extracts catalysed conversion of 18:0-ACP to 18:1(Delta9) but only trace amounts of Delta9-hydroxy fatty acids were formed. A total of four cDNAs were isolated from developing seeds, of both species, using a fragment isolated with PCR amplification. The M. integrifolia acyl-ACP desaturase cDNA was expressed in Escherichia coli. A partly purified fraction of the enzyme showed a 16:0-ACP to 18:0-ACP desaturation ratio about 90-fold less than that in the Macadamia extracts. Expressed N. oleander acyl-ACP desaturase cDNAs showed predominantly 18:0-ACP desaturase activity and no hydroxylase activity. Thus it is not likely that any of the four acyl-ACP desaturases cloned from M. integrifolia or N. oleander is involved in the production of unusual fatty acids.
Macadamia integrifolia seed oil 
