1 National Institute of Aquatic Resources, Technical University of Denmark2 Section for Aquatic Process and Product Technology, National Institute of Aquatic Resources, Technical University of Denmark3 Department of Chemical and Biochemical Engineering, Technical University of Denmark4 National Food Institute, Technical University of Denmark
The accumulation of formaldehyde and the resulting deterioration of seafood products during frozen storage are primarily caused by the enzymatic activity of trimethylamine oxide aldolase (TMAOase). A screening of muscle samples from 24 species showed TMAOase activity in only the nine gadiform species that were analyzed. Enzyme activities in the major white muscle of gadiform fish showed large variations between species as well as between individuals. A frozen storage experiment showed a similarly large variation in the rate of formaldehyde accumulation, which could be accounted for by the endogenous white muscle in situ TMAOase activity. This TMAOase activity also correlated with the rate of insolubilization of otherwise high ionic strength soluble protein. A simple model describing the accumulation of free formaldehyde during frozen storage of gadiform fish is proposed. The model is based on a storage time-dependent decay of substrate-saturated white muscle TMAOase activity.
Journal of Agricultural and Food Chemistry, 2004, Vol 52, Issue 12, p. 3814-3822