Optimization of fat bleaching in soap production: from laboratory to industrial scale

  • Jaqueline C. Duarte
  • Roniérik P. VieiraEmail author
Original Paper


This paper reports the use of design of experiments (DOE) with the objective of finding optimal industrial conditions for fat bleaching in soaps production. Laboratory experiments were performed evaluating the effects of residence time, temperature and pressure on the resulting fat color by two different colors scales: red (R) and yellow (Y), through light emitted or reflected by the mixture. Statistical analysis as well as a visual analysis of response surfaces indicated that only factors “Time”, “Temperature”, “Pressure” and “Time × Temperature” presented considerable effects on the total color, and an operation with long residence time, low pressures and low temperatures would be ideal for removal of the R and Y colors in an easy and effective manner. The responses found in these experiments were reproduced in industrial equipment, and the fat color results obtained were within the indicated experimental value. This approach is of simple laboratory execution, good reproducibility at the industrial level and also with good fat bleaching efficiency. Our finds indicated that 50 min of residence time, 70 °C and 6.7 kPa would be ideal operation conditions in industrial scale.


Fat bleaching Refining Animal fat 



The authors would like to thank Unilever for all support to this study.

Compliance with ethical standards

Conflict of interest

All authors have participated in (a) conception and design, or analysis and interpretation of the data; (b) drafting the article or revising it critically for important intellectual content; and (c) approval of the final version.

Authorship conformation form

This manuscript has not been submitted to, nor is under review at, another journal or other publishing venue.

The authors have no affiliation with any organization with a direct or indirect financial interest in the subject matter discussed in the manuscript.


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Copyright information

© Institute of Chemistry, Slovak Academy of Sciences 2019

Authors and Affiliations

  1. 1.Department of Bioprocesses and Materials Engineering, School of Chemical EngineeringUniversity of CampinasSão PauloBrazil

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