Characterizing and Manipulating Sorghum Kernel Wax as a Possible Alternative for Carnauba Wax

Abstract

Natural waxes are industrial products with many applications. Carnauba wax, from South American palm trees, is the most widely used wax due to high melting point and hardness. There is no domestic source for a natural wax with these characteristics. I characterized and manipulated waxes from domestic Sorghum bicolor kernels to determine if sorghum kernel waxes could be a viable alternative to carnauba. Carnauba’s wax composition is mostly long chain alkyl esters while sorghum is mostly acids and alcohols. To test the hypothesis that long chain wax esters are responsible for carnauba’s high melting point, we fractionated carnauba wax resulting in an alkyl ester-rich fraction and mixed it with sorghum kernel wax to simulate an alkyl ester-rich sorghum kernel wax. Ester-enriched sorghum kernel wax had a melting point of 81.0°C compared to carnauba at 84.9°C, showing that increasing the ester content in sorghum kernel wax results in a substantial increase in melting point.