Nondestructive analysis of salt, water, and protein in dried salted cod using computed tomography.

Computed X-ray tomography (CT) was used to determine NaCl, water, and protein levels in dried salted cod. Cod fillets were salted and dried, and CT was conducted several times during the process. Also, homogenized cod samples with a chemical composition covering the typical composition of cod during salting and drying were produced, and CT scanned. Chemical composition of fillet and model samples was predicted from CT images acquired at 80, 110, and 130 kV. The best average prediction errors (RMSECV) obtained for homogenized samples were 0.6% NaCl, 1.3% water, and 1.5% protein; all explained variances were R2= 0.99 or above. The best RMSECVs and explained variances for cod fillet samples were 0.9% NaCl (R2= 0.96), 0.8% water (R2= 0.99), and 1.4% protein (R2= 0.79). Combining CT values from 2 or 3 voltages gave the best predictions except when predicting salt in cod fillet, where 1 voltage was sufficient.

[1]  Lee W Goldman,et al.  Principles of CT: Radiation Dose and Image Quality* , 2007, Journal of Nuclear Medicine Technology.

[2]  G. Hounsfield Computed Medical Imaging , 1980, Science.

[3]  M. Gómez-Guillén,et al.  Sodium replacement in the cod (Gadus morhua) muscle salting process , 2005 .

[4]  Marit Aursand,et al.  Salting and Desalting of Fresh and Frozen‐thawed Cod (Gadus morhua) Fillets: A Comparative Study Using 23Na NMR, 23Na MRI, Low‐field 1H NMR, and Physicochemical Analytical Methods , 2006 .

[5]  A. Kohler,et al.  Determination of sodium chloride in pork meat by computed tomography at different voltages. , 2008, Journal of food science.

[6]  P. Fito,et al.  Influence of Increasing Brine Concentration in the Cod-Salting Process , 2002 .

[7]  J. Barat,et al.  Analysis of some cod-desalting process variables , 2005 .

[8]  R. L. Olsen,et al.  Rehydration of salt-cured cod using injection and tumbling technologies , 2004 .

[9]  José M. Barat,et al.  A comparative study of brine salting of Atlantic cod (Gadus morhua) and Atlantic salmon (Salmo salar) , 2007 .

[10]  P. Fito,et al.  Cod salting manufacturing analysis , 2003 .

[11]  J. Barat,et al.  Mass transfer analysis during the cod desalting process , 2004 .

[12]  Achim Kohler,et al.  Noncontact salt and fat distributional analysis in salted and smoked salmon fillets using X-ray computed tomography and NIR interactance imaging. , 2009, Journal of agricultural and food chemistry.

[13]  John M Boone,et al.  X-ray imaging physics for nuclear medicine technologists. Part 2: X-ray interactions and image formation. , 2005, Journal of nuclear medicine technology.

[14]  R. L. Olsen,et al.  Physical and quality attributes of salted cod (Gadus morhua L.) as affected by the state of rigor and freezing prior to salting , 2004 .

[15]  Tamás Molnár,et al.  Non-invasive measurement of fillet composition of four freshwater fish species by computer tomography , 2002, Aquaculture International.

[16]  Morten Rye,et al.  Prediction of carcass composition in Atlantic salmon by computerized tomography , 1991 .

[17]  T. Mørkøre,et al.  Quantification of dry matter % and liquid leakage in Atlantic cod (Gadus morhua) using computerised X-ray tomography (CT) , 2008 .

[18]  E. Elvevoll,et al.  Low salt brining of pre-rigor filleted farmed cod (Gadus morhua L.) and the effects on different quality parameters , 2008 .

[19]  H. Skjervold,et al.  In vivo estimation of body composition by computerized tomography , 2010 .

[20]  S. Bogason,et al.  The effects of various salt concentrations during brine curing of cod (Gadus morhua) , 2004 .

[21]  Kari Kolstad,et al.  Quantification of fat deposits and fat distribution in Atlantic halibut (Hippoglossus hippoglossus L.) using computerised X-ray tomography (CT) , 2004 .

[22]  O. Sørheim,et al.  Computed tomography for quantitative determination of sodium chloride in ground pork and dry-cured hams. , 2007, Journal of food science.

[23]  B. Gjerde Predicting carcass composition of rainbow trout by computerized tomography , 1987 .

[24]  J. Barat,et al.  Influence of cod freshness on the salting, drying and desalting stages , 2006 .

[25]  W. Horner Preservation of fish by curing (drying, salting and smoking) , 1997 .

[26]  G N Hounsfield,et al.  Computed medical imaging. Nobel lecture, Decemberr 8, 1979. , 1980, Journal of computer assisted tomography.