3. Results and discussion
3.1. Extraction
The experimental yields of pectin obtained for extraction using three different acids (nitric, acetic and tartaric) are presented in Table 1. Was adjusted a factorial model which analyzed the influences of factors tEx, P and the interaction tEx × P. Multiple regression coefficients are shown in Table 2. The results showed that for extractions carried out with nitric acid and tartaric, both variables (tEx and P) as well as their interactions (tEx × P) was significant by t-Student test at a significance level of 0.05. For the case of extractions performed with acetic acid results suggest that only the extraction time significantly affects the extraction yield. In this case, the power of the microwave is not very important. Thus, the extraction process using acetic acid may be conducted at the lowest level of radiation (356 W) with no damage as the yields obtained.