Synonymous with ritualism and spirituality, the use of sandalwood in incense has been part of life since ancient times due to its striking, natural, and long-lasting fragrance
Sandalwood is a preferred material in incense during meditation and rituals as it’s known to calm the mind while still allowing the person to remain alert. For those who favour its mythical and therapeutic qualities, the spiritual significance takes shape as the burning represents the incineration of negativity to reveal the pure self.
Given the scarcity of certain precious natural ingredients – including Indian sandalwood which was included on the International Union for Conservation of Nature’s vulnerable species list in 1998 due to illegal poaching and harvesting – looking for alternative ways to maximise use of materials and repurpose or reduce waste has become a top priority for many companies.
Leading global producer, Quintis owns and manages one of the largest Indian sandalwood estates in the world and, over the past 20 years, has remained committed to producing Indian sandalwood in a sustainable and natural way, ensuring this versatile ingredient is available for generations to come.
As sustainability goals in the beauty, personal care, and aromatherapy industries advance, new possibilities are being uncovered for materials that once would have been waste. One area making great strides in this regard is upcycling green waste as ingredients, in particular using spent charge as a core component of sustainable incense production.
Spent charge, also known as sandalwood residue, is the exhausted biomass created during the oil distillation process when obtaining sandalwood oil. This residue has traditionally been known as an industrial by-product that was simply discarded as green waste or boiler feed after the steam distillation process.
Instead of disposing of the exhausted biomass, ongoing research and innovation by Quintis has unlocked the potential for grouping this as spent charge. By re-purposing it to create incense products, Quintis has been able to reduce waste and, more than that, continued to add value to sandalwood operations.
More than a passing trend, upcycling spent charge is a vital way for Quintis to make better use of the earth’s resources and reduce our impact on the environment.
In a detailed proprietary process, we have refined over a number of years, the spent charge is extracted from the distillation stills and air dried until the moisture content reduces to the optimal conditions, before being ground into a fine powder and blended with binding materials to make the final incense product.
When gently burnt as an incense, spent charge has a different scent profile to the pure heartwood or distilled essential oil and releases the residual essential oils and other semi-volatiles.
These molecules give a strong, spicy, caramel, amber-like aroma to the spent charge in incense, making it a valued and unique material. The burning process also creates pyrogenic molecules from the wood with a characteristic smoky and woody aroma.
While pure sandalwood heartwood aroma is prized in fragrance and widely valued in incense and aromatherapy, the versatility of spent charge and its extensive usage is still being discovered. The re-purposed spent charge in incense products produces a very captivating and appealing fragrance, leaving consumers with a different sensory experience.
In addition to 100% of the materials from the distillation process being upcycled and therefore making this process zero waste, when it comes to deforestation, spent charge also provides an economical alternative to other wood products usually sourced from tropical rainforests through unsustainable practices.
The rigorous distillation technology and the efficient methods within the upcycling process allow for much of the essential oil to be extracted. The total oil content is typically less than 0.5% of total spent charge weight but, upon burning, the essential oil trapped in the spent charge gets released through evaporation to produce a sandalwood aroma.
As an example of distillation efficiency, Quintis developed a world-first commercial Continuous Steam Distillation plant in 2021. This fully automated process allows Quintis to produce greater volumes of oil at greater speeds – four times more oil with the same volume of steam – reducing our company’s water and energy usage by 75%.
With the ongoing demand for more sustainable products, incense manufacturers are increasingly relying heavily on forest products for their raw materials. Quintis is beginning to see a trend developing from traditional and niche incense manufactures for this unique ingredient, and we expect they will continue to be looking for products created through sustainable practices.
Quintis’s distillation process allows these manufacturers the opportunity to include the unique, distinct aroma and physical properties of the residue in their products, while supporting customers to reach their sustainability goals.
For consumers craving products and experiences that stimulate the senses to bring physical pleasure and mental tranquillity, the olfactory qualities of spent charge in incense sticks creates an incredible and unique essence.
Indian sandalwood spent charge is developing as a product of its own with a distinct odour profile and physical properties. These sensory attributes allow more mindfulness and a unique fragranced environment.