Impact of pulsed light treatments on quality characteristics and oxidative stability of fresh-cut avocado

Abstract

Fresh-cut avocado pieces were subjected to pulse light (PL) treatments on both sides (3.6, 6.0 and 14 J/cm2 per side) with the purpose of evaluating their effect on the microbial burden, color, chlorophyll stability and lipid oxidation for 15 days of storage at 4 °C. Exposure of fresh-cut avocado to the highest dose led to the highest reductions in aerobic mesophylic microorganisms (1.20 log CFU/g) and inhibited the proliferation of yeasts and molds for 3 days, prolonging their microbiological shelf life up to 15 days. Hue values of fresh-cut avocados were better maintained after applying PL treatments. This behavior was partially related with the high chlorophyll retention observed in the same PL-treated samples. In fact, an increment up to around 1.3-fold of chlorophyll a and b was observed after applying 6.0 J/cm2 to fresh-cut avocados. The lipidic fraction of fresh-cut avocados subjected to PL treatments exhibited minimal peroxide formation and stable specific extinction coefficients at 232 and 272 nm for 15 days. These results indicate that the treatments did not result in an increase of rancidity processes, which remained at the induction stage.

This work was supported by the Ministerio de Economía y Competitividad through the Projects AGL2006-04775 and AGL2010-21572. I. Aguiló-Aguayo thanks the Ministerio de Educación y Ciencia (Spain) for awarded PhD grant. ICREA Academia Award is also acknowledged by O. Martín-Belloso.