Little Things Matter: Effect of Minor Constituents on Aroma Profile of Indian Sandalwood Oil
239
Presented by: Dhanushka Hettiarachchi
Introduction
A precious species with a long and sacred history, Indian sandalwood is acclaimed for its aroma and wellness benefits to skin. The complexity and comforting warmth of sandalwood is highly desired, which is evident by its use in over half of the fragrances created for perfume, cosmetics and personal care products. While most of the sandalwood notes used in cosmetics are synthetic bio-mimics or biotechnological isolates, they don’t compare to authentic, complex aroma of natural Indian sandalwood.
The magic of Indian sandalwood oil (ISO) lies in its chemical makeup. Beta-santalol is largely responsible for defining Indian Sandalwood’s soft, creamy, woody aroma, while the dominant of the 125 constituent, alpha-santalol, plays a therapeutic role. ISO oil is also reported to contain minor constituents of different origin, however their composition variation and subsequent effect on the odour profile has not been studied.
Methodology
The current study presents the research conducted in identifying chemical classes of ISO and their olfactory profiling. ISO was industrially distilled from heartwood obtained from sustainable plantations in Australia. Further separations were conducted by fractional distillation, liquid chromatography and preparative thin layer chromatography methods. Chemical analysis was conducted by gas chromatographic mass spectroscopical analysis; constituents were identified by standard databases and published data. Isolated fractions were also subjected to olfactory classification with the help of a professional perfumer and a trained sensory panel.
Results
The major constituents of sandalwood are of sesquiterpene alcohol origin, which includes the alpha and beta santalols. These major constituents show a uniform composition across samples of different origin, without altering the odour profile. However, minor constituents such as sequiterpene hydrocarbons, monoterpenes, oxidised sesquiterpenes, organic acids and by-products of wood fibres, which varied in origin, and had a significant variance in chemical composition had a markable change in olfactory profile. These minor constituents which made up less than 10% of total oil mass made a significant change to the aroma profile of the essential oil. Odour profile and chemical composition was graphed to identify the effect of each minor constituent class on aroma of ISO.
Discussion and Conclusion
Minor constituents contribute to the unique aroma of natural ISO, a unique balance of these constituents is required for specific uses such as fine perfumery and fragrance in cosmetics. Unlike synthetic or biotechnologically developed molecules, natural ISO has the complete odour profile of the sandalwood note. Understanding the chemical contribution of minor constituents has helped to develop customised aroma profiles with elongating fragrance and enhancing sillage.
A precious species with a long and sacred history, Indian sandalwood is acclaimed for its aroma and wellness benefits to skin. The complexity and comforting warmth of sandalwood is highly desired, which is evident by its use in over half of the fragrances created for perfume, cosmetics and personal care products. While most of the sandalwood notes used in cosmetics are synthetic bio-mimics or biotechnological isolates, they don’t compare to authentic, complex aroma of natural Indian sandalwood.
The magic of Indian sandalwood oil (ISO) lies in its chemical makeup. Beta-santalol is largely responsible for defining Indian Sandalwood’s soft, creamy, woody aroma, while the dominant of the 125 constituent, alpha-santalol, plays a therapeutic role. ISO oil is also reported to contain minor constituents of different origin, however their composition variation and subsequent effect on the odour profile has not been studied.
Methodology
The current study presents the research conducted in identifying chemical classes of ISO and their olfactory profiling. ISO was industrially distilled from heartwood obtained from sustainable plantations in Australia. Further separations were conducted by fractional distillation, liquid chromatography and preparative thin layer chromatography methods. Chemical analysis was conducted by gas chromatographic mass spectroscopical analysis; constituents were identified by standard databases and published data. Isolated fractions were also subjected to olfactory classification with the help of a professional perfumer and a trained sensory panel.
Results
The major constituents of sandalwood are of sesquiterpene alcohol origin, which includes the alpha and beta santalols. These major constituents show a uniform composition across samples of different origin, without altering the odour profile. However, minor constituents such as sequiterpene hydrocarbons, monoterpenes, oxidised sesquiterpenes, organic acids and by-products of wood fibres, which varied in origin, and had a significant variance in chemical composition had a markable change in olfactory profile. These minor constituents which made up less than 10% of total oil mass made a significant change to the aroma profile of the essential oil. Odour profile and chemical composition was graphed to identify the effect of each minor constituent class on aroma of ISO.
Discussion and Conclusion
Minor constituents contribute to the unique aroma of natural ISO, a unique balance of these constituents is required for specific uses such as fine perfumery and fragrance in cosmetics. Unlike synthetic or biotechnologically developed molecules, natural ISO has the complete odour profile of the sandalwood note. Understanding the chemical contribution of minor constituents has helped to develop customised aroma profiles with elongating fragrance and enhancing sillage.