Revisiting the role of total fatty matter in soap bars

More than 10 million tonnes of metal salts of fatty acids are manufactured worldwide every year, to create a range of soft condensed-matter cosmetic products such as bar soaps, liquid washes, deodorant sticks, skin creams, toothpastes, and so on. These salts, popularly known as soaps, mainly use palm or tallow-based oils as the source of fatty acids. Soap bars comprised of more than 80% soaps alone account for a significant part of the global oil/fat footprint in non-edible usage. The COVID pandemic highlighted the need for hygiene and germ protection, thereby driving the consumption of soap bars further. Providing these personal hygiene assets to all strata of society while minimizing the negative impact on the environment through increased material consumption is a critical challenge faced by the soap industry today. Considerable research is ongoing toward making more sustainable soap bars by reducing the use of oils/fats without compromising the sensory and functional performance. Another challenge faced is that in many geographies, soap bars must comply with regulatory standards which mandate minimum levels of oils/fats (called TFM—total fatty matter) in the product with no reference to the performance or benefits provided. What this paper will demonstrate is that there are technologies to manufacture soap bars that meet the desired product performance independent of the level of TFM. These technologies have the potential to provide formulation flexibility and environmental benefits by opening the ingredient space and cutting down significantly on greenhouse gas emissions through reduced consumption of oils.