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Sigurjón Arason
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Water distribution in commercial Icelandic heavily salted Atlantic cod (Gadus morhua) / Water distribution in fully salted cod
Water distribution in a variety of products from Icelandic fully salted cod was analyzed using proton magnetic resonance imaging methods. The products were both flat and filleted, in addition to which they varied in terms of fishing methods, processing before or after death hardening, pre-salting methods (injection salting with / without phosphate, brine and brine salting) as well as the choice of injection machines. All products had an even water distribution, but the homogeneity depended on processing methods. Double injection of salt, as well as simple injection into a muscle before death, led to needle punctures in the muscle, which were even detectable after "kench" salting. Analysis of relaxation time indicated that brine salting led to high muscle protein depletion compared to other pre-salting methods. Injection salting led to a salt-inducing swelling in the muscle, and this effect was maintained even after the "kench" salting step. Multivariate analysis of all variables showed that the MR methods are powerful methods for evaluating the processing properties of products, as well as for maximizing processing methods.
The water distribution of various commercially available Icelandic heavily salted Atlantic cod) products were analyzed with proton magnetic resonance methods. The products varied in choice of catching method, in pre ‐ or post ‐ rigor processing, flattening or filleting cut, and pre ‐ salting technique (brine injection with salt with / without polyphosphates, brining and pickling) and choice of brine injection instruments. All products had a heterogeneous water distribution, but the level of heterogeneity was dependent on the handling during processing. Double brine injection and brine injection into pre ‐ rigor muscle lead to needle traces in the muscle, even after kench salting. Relaxation time analysis indicated that pickle salting leads to the highest degree of protein denaturation in the muscle of the analyzed pre ‐ salting methods. Brine injection lead to salt ‐ induced swelling, which effect remained after the kench salting step. The multi ‐ parametric analysis performed indicated how powerful the MR methods are for process and product characterization and optimization.