5. Conclusions
HPP has proved to be a promising emerging technology, able to
render sound fresh-cut fruits. In the present study, we demonstrated
the beneficial effect of HPP (500 MPa-5 min) on the quality
of the product and the extension of the shelf life, especially when
combined with other preserving strategies (organic acids, vacuum
packaging and refrigerated storage). Color and texture of fresh-cut
peaches subjected to the combination of HPP þ VP could be well
preserved for at least 21 days under refrigerated storage (10 C),
with only minor alterations such as translucency of tissues.
Vacuum-packaging, a technology that guarantees the absence of
oxygen inside the packaging, contributed to the preservation of
color by inhibiting the in-pack enzymatic browning. On the other
hand, when the packagewas opened and the product re-exposed to
the normal oxygen concentration, browning was prevented
because of the partial inhibition of PPO brought about by the
concomitant effect of HPP treatment þ organic acid dipping. HPP
was also effective to control the fermentative metabolism that
would have been otherwise induced by vacuum. This effect was
evidenced by the low content of ethanol found in the pressurized
samples during the entire storage time.
Additional studies are currently underway in our lab to determine
the effects of HPP on aspects such as the inhibition of different
enzymes (PME and PG, responsible for textural changes; ADH and
PDC, involved in the fermentative metabolism), and the microbiological,
sensorial and nutritional attributes of fruits subjected to the
HPP-VP combination. These studies will help gain a deeper
knowledge to determine their feasibility of application, and evaluate
their capacity to extend the shelf life of fresh-cut fruits and
vegetables.