Food Sci Technol Int. 2015 Sep 18. pii: 1082013215606832. [Epub ahead of print]
Abstract
A
combination of different hurdles, such as mild heat (54 ℃ for 10 min)
or pulsed electric field (25 pulses; 25 kV/cm; 3.35 kJ/cm per pulse)
treatments and essential oils
constituents (carvacrol, citral, and (+)-limonene), to reduce spoiling
bacteria and yeasts in apple juice was evaluated. For this purpose, the
heat and pulsed electric field resistances of five strains of
Leuconostoc spp. and five Saccharomyces spp. strains were assayed,
achieving different inactivation levels for each treatment and strain.
For instance, Leuconostoc fallax 74, the most heat-resistant strain, was
the second-most sensitive strain to pulsed electric field. The most
resistant strains were exposed to combined processes of heat or pulsed
electric field and 0.2 µl/ml essential oils constituents. The combination of heat and essential oils
constituents proved to be synergistic against both microorganisms in
apple juice. The most effective was the combination of mild heat and
carvacrol, which caused the inactivation of 99% of L. fallax 74 and
99.99% of Saccharomyces cerevisiae CECT 1172 cells. Therefore, this
study shows the great potential of carvacrol, citral, and (+)-limonene
in combined treatments with mild heat to achieve a higher degree of
inactivation of spoiling microorganisms in apple juice, and thus, to
extend its shelf life.
© The Author(s) 2015.
© The Author(s) 2015.
