The Brazillian Health Surveillance Agency (ANVISA, 1999) does not present a specification of acidity to jatropha, however, all the results of acidity posterior to neutralization are within the limit of 2mg of KOHg−1 of oil determined by this legislation to other oilseeds. Tapanes (2008) states that for the acidity of jatropha to be lower than 1.5mgKOHg−1 a basic homogeneous transesterification may be performed.