Description

Olive Oil Propylene Glycol Esters are derived from the esterification of olive oil with propylene glycol. They serve as multifunctional ingredients in personal care and cosmetic formulations due to their emollient, emulsifying, and conditioning properties.

Chemical Composition and Structure

Components: The primary components are olive oil (which contains various fatty acids such as oleic acid, linoleic acid, and palmitic acid) and propylene glycol. The esterification reaction involves the formation of ester bonds between the fatty acids from the olive oil and propylene glycol.
Chemical Formula: The exact chemical formula depends on the specific fatty acids involved, but the general formula can be represented as R-COO-CH2CHOH-CH2OH, where R represents the fatty acid chain.
Structure: The molecular structure consists of an ester functional group (R-COO-) bonded to the propylene glycol moiety (CH2CHOH-CH2OH).

Physical Properties

Appearance: Typically a clear to slightly cloudy liquid, depending on the concentration and formulation.
Odor: Mild, characteristic of olive oil, which can be described as slightly nutty or herbal.
Solubility: Soluble in organic solvents and oils, such as mineral oil, and generally insoluble in water. This property makes it effective as an emulsifier in oil-based formulations.
Melting Point: Not specifically applicable as it is generally a liquid at room temperature, though its melting point would be influenced by the specific fatty acids and propylene glycol content.

Production Process

Esterification Reaction:
Olive oil is reacted with propylene glycol in the presence of an acid catalyst (often sulfuric acid) to facilitate the esterification process.
The reaction is carried out under controlled conditions of temperature and pressure to ensure complete conversion of the reactants into esters.
Purification:
The reaction mixture is neutralized to remove the catalyst.
The product is then purified through techniques such as distillation or filtration to remove any residual unreacted propylene glycol, fatty acids, and by-products.
Standardization:
The final product is standardized to ensure consistent quality and performance. This may include testing for ester content, solubility, and other relevant parameters.

Applications

Cosmetics:
Emollient: Improves skin hydration and smoothness by forming a barrier on the skin that prevents moisture loss.
Emulsifier: Helps blend oil and water phases in formulations, ensuring a stable product with a uniform texture.
Conditioning Agent: Enhances the feel and appearance of skin and hair by providing a soft and silky touch.
Personal Care Products:

Skin Care: Used in creams, lotions, and serums to provide moisturizing and conditioning benefits.
Hair Care: Incorporated into conditioners and styling products for added shine and manageability.
Food: Not typically used in food applications due to its primary role in cosmetics and personal care.

Environmental and Safety Considerations

Biodegradability: Olive Oil Propylene Glycol Esters are derived from natural sources and are generally biodegradable, which contributes to their environmental compatibility.
Safety Profile: Considered safe for topical use in cosmetics. They are non-toxic and non-irritating to the skin when used within recommended concentrations.
Regulations: Subject to cosmetic regulations which ensure they meet safety and efficacy standards. It is important to follow established guidelines to avoid potential allergic reactions or skin irritations.

Studies

In the olive there are bioactive compounds useful for human health such as polyphenols, proteins.
Montealegre C, Esteve C, García MC, García-Ruiz C, Marina ML. Proteins in olive fruit and oil. Crit Rev Food Sci Nutr. 2014;54(5):611-24. doi: 10.1080/10408398.2011.598639. Review.
Abstract. This paper is a comprehensive review grouping the information on the extraction, characterization, and quantitation of olive and olive oil proteins and providing a practical guide about these proteins. Most characterized olive proteins are located in the fruit, mainly in the seed, where different oleosins and storage proteins have been found. Unlike the seed, the olive pulp contains a lower protein content having been described a polypeptide of 4.6 kDa and a thaumain-like protein. Other important proteins studied in olive fruits have been enzymes which could play important roles in olives characteristics. Part of these proteins is transferred from the fruit to the oil during the manufacturing process of olive oil. In fact, the same polypeptide of 4.6 kDa found in the pulp has been described in the olive oil and, additionally, the presence of other proteins and enzymes have also been described. Protein profiles have recently been proposed as an interesting strategy for the varietal classification of olive fruits and oils. Nevertheless, there is still a lot of knowledge without being explored requiring new studies focused on the determination and characterization of these proteins.

The amount of phenolic compounds is significant and explains the antioxidant activity of olive and olive oil:
phenols are present in quantities between 317mg/100g and 2657mg/100g.
gallic acid from 7mg/100g to 35mg/100g
3,4-Dihydroxybenzoic acid 33mg/100g to 25mg/100g
These values change substantially depending on the type of oleander, harvest period and other parameters.
Özcan MM, Fındık S, AlJuhaimi F, Ghafoor K, Babiker EE, Adiamo OQ. The effect of harvest time and varieties on total phenolics, antioxidant activity and phenolic compounds of olive fruit and leaves. J Food Sci Technol. 2019 May;56(5):2373-2385. doi: 10.1007/s13197-019-03650-8.
Abstract. The effect of harvest periods on total phenol, antioxidant activity, individual phenolic compounds of fruit and leaves of Tavşan Yüreği, Memecik, Edremit, Ayvalık and Gemlik olive varieties grown in Turkey were investigated. The highest total phenol (317.70 mg/100 g and 2657.81 mg/100 g) were observed in Tavşan Yüreği olive fruit and Ayvalık leaves harvested in December, respectively. The highest antioxidant activities (83.84%) were determined in Edremit fruit harvested in August and 83.33% in either Edremit olive leaves harvested in November and Tavşan Yüreği leaves harvested in December. The olive fruit contained gallic acid ranging from 7.18 mg/100 g (August) to 35.85 mg/100 g (December) in case of Ayvalık and 2.09 mg/100 g (November) to 21.62 mg/100 g (December) in Edremit. Gemlik olives showed higher gallic acid contents compared to the other varieties, however it depended significantly on harvest time in all cases. 3,4-Dihydroxybenzoic acid contents ranged from 33.11 mg/100 g (October) to 25.17 mg/100 g (September) in Memecik olives; 12.17 mg/100 g (August) to 33.11 mg/100 g (December) in case of Tavşan Yüreği olives depending on harvest time. The 3,4-dihydroxybenzoic acid contents of Memecik leaves ranged between 122.25 mg/100 g (September) to 196.58 mg/100 g (August) and that of Tavşan Yüreği leaves changed between 99.38 mg/100 g (November) and 179.90 mg/100 g (August). The leaves of these two varieties contained significantly (p < 0.01) higher 3,4-dihydroxybenzoic acid contents than other varieties. The highest gallic acid (144.83 mg/100 g) was detected in Memecik leaves (September) whereas lowest were found in Gemlik leaves collected in October.

The good protein and amino acid content of olive and in particular maslinic acid, a tripenoid, have shown that, together with moderate exercise, they can increase muscle mass, grip strength, knee pain and thus prevent disability related to mobility in older people.
Nagai N, Yagyu S, Hata A, Nirengi S, Kotani K, Moritani T, Sakane N. Maslinic acid derived from olive fruit in combination with resistance training improves muscle mass and mobility functions in the elderly. J Clin Biochem Nutr. 2019 May;64(3):224-230. doi: 10.3164/jcbn.18-104. Epub 2019 Mar 7. PMID: 31138956; PMCID: PMC6529705.
Abstract. Maslinic acid, derived from olive fruit, reduces pro-inflammation cytokines, which are involved in muscle fiber atrophy. Therefore, the maslinic acid ingestion may enhance the muscular response to resistance training through anti-inflammatory action. We therefore conducted a parallel, double-blind, randomized, placebo-controlled trial that examined whether a combination of maslinic acid supplementation and resistance training improve mobility functions in community-dwelling elderly persons. Over a 12-week period, 36 participants underwent moderate resistance training and are assigned to the maslinic acid supplementation (n = 17, 60 mg/day) or the placebo (n = 19) group. At baseline and at 12-weeks, we assessed body composition, grip strength, walking speed, leg strength, mobility functions, and knee pain scores. Following the 12-weeks, skeletal muscle mass, segmental muscle mass (right arm, left arm, and trunk) and knee pain score of the right leg were significantly improved in the maslinic acid group, while there was no change or parameters had worsened in the placebo group. Grip strength of the better side significantly increased only in the maslinic acid group. These results suggest that maslinic acid supplementation combined with moderate resistance training may increase upper muscle mass and grip strength, and reduce knee pain, could be effective for preventing mobility-related disability in elderly persons. Clinical trial registration number: UMIN000017207.

INCI Functions:


Skin conditioning agent - Emollient. Emollients have the characteristic of enhancing the skin barrier through a source of exogenous lipids that adhere to the skin, improving barrier properties by filling gaps in intercorneocyte clusters to improve hydration while protecting against inflammation. In practice, they have the ability to create a barrier that prevents transepidermal water loss. Emollients are described as degreasing or refreshing additives that improve the lipid content of the upper layers of the skin by preventing degreasing and drying of the skin. The problem with emollients is that many have a strong lipophilic character and are identified as occlusive ingredients; they are oily and fatty materials that remain on the skin surface and reduce transepidermal water loss. In cosmetics, emollients and moisturisers are often considered synonymous with humectants and occlusives.
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