Abstract
The development of restructured fish products
and the application of new food ingredients have been
used to create attractive new products and also to upgrade
low-value species. The aim of this study was to
evaluate the effect of konjac gum (KGM) and carboxymethylcellulose
(CMC) fibres on the mechanical and
physico-chemical properties of microbial transglutaminase
treated restructured fish products from gilthead
sea bream as well as to evaluate the effect of heat
treatment and storage time. Water holding capacity, mechanical
properties and colour attributes in fresh and
heat-treated samples after 15 days of cold storage were
measured. Results showed that these edible gums could
be appropriate for making restructured products obtained
from gilthead sea bream. In fresh formulations the addition
of 10 gkg−1 of KGM or 10 gkg−1 of CMC
presented a significant effect (p¡Ü0.05) on water activity
for fresh samples and the lowest value was obtained for
10 gkg−1 of KGM (0.975¡À0.002). Water holding capacity
and adhesiveness increased due to the presence of
these gums in fresh and heat-treated samples. For heattreated
samples, KGM significantly reduced (p<0.05)
hardness, cohesiveness and chewiness. Cryo-scanning
electron microscopy revealed different structures for gels
containing fibres. The use of these fibres did not induce
significant changes in colour parameters. Fresh or heattreated
samples stored for 15 days at 4¡ãC showed changes in
relation to the parameters investigated.