The same parameters were optimized for the liposoluble standards diluted with AVK (standard method). The optimized aspiration rate and fuel/oxidant ratio for the determination of Ca, Mg and Zn are shown in Table 1. As can be seen, the fuel/oxidant ratio was similar for the proposed method and dilution method, except for Mg, for which a different flame compositions were used in both method. In this work the stability of absorption measurements were not greatly affected by the presence of kerosene, as observed in a previous work of our group for biodiesel analysis using the dilution with xylenemethod[24,29]. However, regarding the threecomponent solution, the behavior was similar to that observed for biodiesel microemulsion, not affecting significantly the flame stability [24,29]. Even though, the best signal/BG ratio was obtained with fuel/oxidant ratio close to the minimum for Ca and Mg, for both methods. The aspiration rate that gave the best sensitivity for dilution with kerosene was also close to the minimum allowed in our equipment for this solution. On the other hand, for the threecomponent solution, which is more viscous than the kerosene solution, the aspiration rate of 1.5mLmin−1, that is not the minimum, gave the best sensitivity. These optimized conditions were used in all subsequent studies.