The macauba pulp esters comply with the ANP specifications in all analyzed temperatures in the range 850.0–900.0 kg m-3at20°C. The results are similar to those verified by Aguieiras et al.
[16] at 20°C obtained in enzymatic hydroesterification of macauba acid oil. Density of biodiesel is directly related to its molecular structure. The greater the length of the alkyl ester carbon chain, the greater the density. However, this value will decrease as the rate of unsat- uration in the molecule increases[40] . The presence of impurities could also influence biodiesel density; for example, alcohol or adulterant substances [31] .Fig. 5 shows a marked decrease in oil viscosity as temperature rises. The macauba pulp oil and the ethyl ester, between the tem-peratures of 20 and