Washing performance of Soap nut shells

  • University of Zagreb Faculty of Textile Technology
  • University of Zagreb, Faculty of Textile Technology
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Investigations of washing agents are interesting from the technological and environmental point of view. The trend towards natural ingredients is growing and vegetable-derived surfactants are gaining popularity in "green formulations". Soap nut tree, Sapindus mukorossi, is a source of natural surfactants, saponins. Surface active matter and pH of the aqueous extract have been analysed. Primary and secondary washing effect of soap nuts is studied at different temperatures, 60 and 90 °C, applying naturally soiled cotton fabrics. Simultaneously, reference and commercial powder detergents from Croatian market are tested. Good washing performance of soap nut shells evaluated through primary effect was obtained especially at 90 °C. Beneficial multiple washing performance of natural saponins have been confirmed through less ash content as well as low level of mechanical damage. Total washing performance of soap nut shells provides many benefits for consumer from technological and ecological point of view.

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