Microwave processing of avocado: Volatile flavor profiling and olfactometry

The aim of this research was to evaluate the effect of microwave time, pH and avocado leaves on the volatile profile of avocado using response surface methodology, and aroma extract dilution analysis (AEDA) was employed to evaluate changes in the odorant composition. Response surface analyses showed maximum values for volatiles derived from lipid oxidation at high levels of microwave time and low values of pH. The presence of terpenoids, estragole, hexanal and 2-hexenal [E] was enhanced with the addition of avocado leaves. The optimum condition to prepare avocado puree was 30 s heating time, pH 5.5 and 1% of leaves. Comparative AEDA analysis for microwaved avocado puree added with and without avocado leaves showed changes in the FD of compounds derived from lipids. In addition, AEDA suggests that the addition of avocado leaves to microwaved avocado is related to the presence of important odorants such α-pinene, estragole and 2-hexenal [E]. Industrial relevance: Several attempts have been made to process avocados as purée or "guacamole". Microwave treatment offers an alternative for the blanching of fruits and vegetables, since the application of high temperatures for short times often results in minimum damage. Furthermore, previous studies have shown that better retention of color and lightness is obtained when avocado purée is processed in a microwave oven. However, a great loss of flavor takes place when this commodity is treated by heat. The application of a combined treatment consisting of microwaves, pH and the addition of avocado leaves to the purée minimizes flavor loss and results in a product with the characteristic flavor of avocado.