The effect of freeze-thawing on the magnetic resonance imaging parameters of cod and mackerel

Magnetic Resonance Imaging (MRI) was used to measure the MR parameters of w ater (T-1, T-2, T-1(sat), M-sat, M-0 and the Magnetisation Transfer (MT) ra te) in fresh and frozen-thawed con (Gadus morhua) and mackerel (Scomber sco mbrus); those species were chosen to be representative of the demersal and pelagic marine fish, respectively. Samples of a cod were obtained 'fresh' f rom a local fish market and as cod fillets in an Individually Quick Frozen (IQF) state. The extent of deterioration during storage was,monitored over 2, 4, 8 and 12 wk periods. It was found that T-1, T-1(sat) and MT rate were particularly sensitive to the effects of frozen storage. (C) 1999 Academic Press.