18 JOURNAL OF COSMETIC SCIENCE
The system depicted in Figure 8 comprises an emulsifier blend of Polyglyceryl-3 Distearate
and Glyceryl Stearate Citrate, consistency enhancers including Glyceryl Stearate and
Cetearyl Alcohol, an oil phase comprising four conventional esters derived from non-RSPO
feedstock, a sensory aid in the form of Cellulose, a water phase with Xanthan Gum as
a thickener, and Glycerin. To assess the environmental impact of this binary emulsion,
we replaced the non-RSPO palm-based metal-catalyzed esters with RSPO palm-derived
enzymatically processed esters. The emollient mixture in this oil-in-water formulation
constitutes 18% of the system, as illustrated in Figure 9, and has the most significant effect
on the CO
2
footprint of a typical oil-in-water system.
Upon closer examination, it is evident that the life cycle assessment of ester emollients
in an oil-in-water emulsion is significantly impacted by the choice of feedstocks and
manufacturing processes. Figure 10 illustrates three scenarios, each with varying raw
material choices and production methods. As previously established, esters have the largest
environmental impact, and thus, our focus is on optimizing this group of ingredients.
Figure 8. Environmental impact of a market product: O/W cream.
Figure 9. Environmental impact of a market product: Life cycle assessment of an O/W cream – Impact of
ingredient types.

19 Bottle Your Sustainability Goals – Minimize
The first bar represents the impact of esters made with non-RSPO raw materials and a
conventional production process. The second bar depicts the improvement in the life cycle
assessment achieved by using RSPO mass balance (MB) grade esters with conventional
processing, resulting in a 47% reduction in CO
2
footprint. The third bar shows a further
reduction in environmental impact by combining RSPO MB raw materials with enzymatic
processing. By incorporating enzymatically processed emollients in the final formulation,
a 67% reduction in CO
2
footprint can be achieved, leading to a more sustainable product.
PHYSIOCHEMICAL PROPERTIES OF LIQUID LIPOPHILIC EMOLLIENTS
Figure 11 provides a visual representation of four key attributes of emollients, including
viscosity, surface tension, spreadability, and polarity. The x-axis represents the viscosity of
the emollients, which indicates their fatty characteristic, while the y-axis shows the surface
tension. The size of the circle indicates the spreadability of the emollient. The polarity of
the emollient is also shown on this chart by the color depth of the circles, which indicates
its ability to solvate lipophilic crystalline structures such as avobenzone or ceramides. The
esters which are produced via enzymatic esterification are highlighted on this chart.
Of particular interest is Isoamyl Laurate, which is emollient #2 on the chart. This ester has
an extremely low viscosity and low surface tension, which lends to excellent spreadability,
and it is medium polar, so it can function as a solvating agent. In cosmetic applications,
emollients are utilized for their solvating and sensorial attributes on skin, but we can also
view this class of sustainable ingredients as practical solutions for chemistries that are
falling out of favor due to environmental concerns.
To illustrate this point, a high-spreading enzymatic emollient, Isoamyl Laurate, was used
in place of 6% ethanol to achieve a lower VOC of 55%. This emollient was chosen due to
its physicochemical properties, such as spreadability, which could mimic the behavior of
ethanol in this matrix.
Figure 10. Environmental impact of a market product: Life cycle assessment of an O/W cream – cradle-to-gate.