The great water availability, high temperatures and light throughout the year favor the
development of fish in the state of Tocantins. This study aimed to evaluate and correlate
the physical-chemical and microbiological changes of whole Tambaqui (Colossoma
macropomum), with the storage period on ice (20 days); grown in net tanks and
excavated tanks. In addition, a variation in eye color during the storage period was
evaluated by colorimetry, seeking to identify a color pattern that is related to the
freshness of the fish. The presence of coagulase positive Staphylococci was identified in
the musculature and in the skin swab, in both types of cultures, in quantities greater than
those permitted by sanitary norms (standard for musculature). Salmonella and coliforms
were detected at 45ºC (> 1,1x103 NMP / g) in samples of muscle, water and skin swab,
from a net and excavated tank. No typical colonies of Escherichia coli were identified
in the musculature of any specimen analyzed, supplied in the water and in the skin
mucus swab (net and excavated tanks). The total count of aerobic mesophilic bacteria
did not show a correlation of deterioration with storage time, whereas psychrotrophic
bacteria showed greater bacterial growth as time increased. The average pH values for
net-tank ranged from 6.80 to 7.54, and for excavated tank, it was between 6.15 and 6.78,
and humidity values ranged from 76.83% to 80.59%, in two types of cultivation. There
were no significant changes in the values of proteins, lipids, a decrease in minerals
during the storage period. Under the conditions of the present experiment, the
colorimeter showed satisfactory results that may subsidize its use as an important tool in
the evaluation of eyes to assess the freshness of the fish.
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