Abstract:

This study aimed to analyze the changes in the contents of adenosine triphosphate (ATP)-related compounds
in grass carp muscle during cold storage and to correlate the content of each ATP-relate compound and fish freshness.
The unstable ATP-related compounds were converted into their sodium salt forms by using strong alkaline, which were
separated by high performance liquid chromatography (HPLC). The freshness of grass carp during cold storage was assessed
with respect to total volatile base nitrogen (TVB-N) and sensory scores. The results showed that the sodium salt forms of
ATP-related compounds were well separated. Fresh fish meat contained high levels of inosine monophosphate (IMP), up to
504.34 mg/kg. The levels of ATP and IMP were decreased rapidly during cold storage, whereas hypoxanthine (Hx) contents
were increased quickly over a storage period of 2 d. ATP was not detected after cold storage; IMP was decreased by 92.77%,
while Hx level was increased by 89.82%. TVB-N value always showed an upward trend during cold storage and exceeded
the maximum limit on the 6th day. Thus, the refrigerated shelf life of grass carp was within 6 days with respect to freshness.

Key words: grass carp, ATP-related compounds, nucleotides, freshness